1R: One room with no separate kitchen.
1K: One room with a separate kitchen.
1DK: One room with a separate dining room/kitchen.
1LDK: One large bedroom and a separate living/dining room/kitchen.
2DK: Two rooms with a separate dining room/kitchen.
2LDK: Two bedrooms and a living/dining room/kitchen.
3DK: Three rooms with a separate dining room/kitchen.
3LDK: Three rooms and a living/dining room/kitchen.
N.B. These apartments are not shown to scale. However, all Japanese rooms are based on the tatami mat. One mat is 163 centimeters by 81.5 centimeters (about 5' 4" x 2' 7"). A standard room has six mats. In the images above, the rooms with blue stars are all the same size.


My Old Yearbook CD is a Compact Disk that contains a High School yearbook. We have over 4,500 yearbooks in our library from all over the United States.
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This site and Reunions magazine are your comprehensive source of reunion resources, tips, ideas and advice to help plan your reunion.


text:
Q: ASP.NET Core Identity invalid token on confirmation email This is a very similar question to this
aspnet identity invalid token on confirmation email
but the solutions are not valid because I am using the new ASP.NET Core 1.0 that includes ASP.NET Core Identity.
My scenario is as follows:

*

*In the back end (ASP.NET Core) I have a function that sends a password reset email with a link. In order to generate that link I have to generate a code using Identity. Something like this.
public async Task SendPasswordResetEmailAsync(string email)
{
    //_userManager is an instance of UserManager<User>
    var userEntity = await _userManager.FindByNameAsync(email);
    var tokenGenerated = await _userManager.GeneratePasswordResetTokenAsync(userEntity);
    var link = Url.Action("MyAction", "MyController", new { email = email, code = tokenGenerated }, protocol: HttpContext.Request.Scheme);
     //this is my service that sends an email to the user containing the generated password reset link
     await _emailService.SendPasswordResetEmailAsync(userEntity , link);
}

this would generate an email with a link to:
http://myapp:8080/passwordreset?code=CfDJ8JBnWaVj6h1PtqlmlJaH57r9TRA5j7Ij1BVyeBUpqX+5Cq1msu9zgkuI32Iz9x/5uE1B9fKFp4tZFFy6lBTseDFTHSJxwtGu+jHX5cajptUBiVqIChiwoTODh7ei4+MOkX7rdNVBMhG4jOZWqqtZ5J30gXr/JmltbYxqOp4JLs8V05BeKDbbVO/Fsq5+jebokKkR5HEJU+mQ5MLvNURsJKRBbI3qIllj1RByXt9mufGRE3wmQf2fgKBkAL6VsNgB8w==

*Then my AngularJs application would present a view with a form to enter and confirm the new password, and would PUT a JSON object with the new password and the code that got from the query parameter in the URL.

*Finally my back end would get the PUT request, grab the code and validate it using Identity like this:
[HttpPut]
[AllowAnonymous]
[Route("api/password/{email}")]
public async Task<IActionResult> SendPasswordEmailResetRequestAsync(string email, [FromBody] PasswordReset passwordReset)
{
    //some irrelevant validatoins here
    await _myIdentityWrapperService.ResetPasswordAsync(email, passwordReset.Password, passwordReset.Code);
    return Ok();
}

The problem is that Identity responds with an

Invalid token

error. I have found that the problem is that the codes don't match and the above code would be received back in the JSON object in the PUT request as follows:
CfDJ8JBnWaVj6h1PtqlmlJaH57r9TRA5j7Ij1BVyeBUpqX 5Cq1msu9zgkuI32Iz9x/5uE1B9fKFp4tZFFy6lBTseDFTHSJxwtGu jHX5cajptUBiVqIChiwoTODh7ei4 MOkX7rdNVBMhG4jOZWqqtZ5J30gXr/JmltbYxqOp4JLs8V05BeKDbbVO/Fsq5 jebokKkR5HEJU mQ5MLvNURsJKRBbI3qIllj1RByXt9mufGRE3wmQf2fgKBkAL6VsNgB8w==

Notice that where there was + symbols now there are spaces  symbols and obviously that causes Identity to think the tokens are different.
For some reason Angular is decoding the URL query parameter in a different way that was encoded.
How to resolve this?

A: I have tried the answers above, but this guide has helped me. Basically, you would need to encode the code, otherwise, you would encounter some weird bugs. To summarise you would need to do this:
string code = HttpUtility.UrlEncode(UserManager.GenerateEmailConfirmationToken(userID));

After this, if it is applicable to you, decode code:
string decoded = HttpUtility.UrlDecode(code)

A: After scaffolding the ConfirmEmail page in my Asp.Net Core 3.0 project I ran into the same problem.
Removing the following line from the OnGetAsync method in ConfirmEmail.cshtml.cs fixed the problem:
code = Encoding.UTF8.GetString(WebEncoders.Base64UrlDecode(code));

In the scaffolded Login page, the code is added to the callbackUrl which is then URL encoded using HtmlEncoder.Default.Encode(callbackUrl). When the link is clicked the decoding is automatically done and the code is like it should be to confirm the email.
UPDATE:
I noticed that during the Forgot Password process the code is Base64 encoded before being put in the callbackUrl which then means that the Base64 decode IS necessary.
A better solution would thus be to add the following line to wherever the code is generated before adding it to the callbackUrl.
code = WebEncoders.Base64UrlEncode(Encoding.UTF8.GetBytes(code));

Here is a link to the issue which has been fixed.

A: This answer https://stackoverflow.com/a/31297879/2948212 pointed me in the right direction. But as I said it was for a different version and now it is slightly different solution.
The answer is still the same: encode the token in base 64 url, and then decode it in base 64 url. That way both Angular and ASP.NET Core will retrieve the very same code.
I needed to install another dependency to Microsoft.AspNetCore.WebUtilities;
Now the code would be something like this:
public async Task SendPasswordResetEmailAsync(string email)
{
    //_userManager is an instance of UserManager<User>
    var userEntity = await _userManager.FindByNameAsync(email);
    var tokenGenerated = await _userManager.GeneratePasswordResetTokenAsync(userEntity);
    byte[] tokenGeneratedBytes = Encoding.UTF8.GetBytes(tokenGenerated);
    var codeEncoded = WebEncoders.Base64UrlEncode(tokenGeneratedBytes);
    var link = Url.Action("MyAction", "MyController", new { email = email, code = codeEncoded }, protocol: HttpContext.Request.Scheme);
     //this is my service that sends an email to the user containing the generated password reset link
     await _emailService.SendPasswordResetEmailAsync(userEntity , link);
}

and when receiving back the code during the PUT request
[HttpPut]
[AllowAnonymous]
[Route("api/password/{email}")]
public async Task<IActionResult> SendPasswordEmailResetRequestAsync(string email, [FromBody] PasswordReset passwordReset)
{
    //some irrelevant validatoins here
    await _myIdentityWrapperService.ResetPasswordAsync(email, passwordReset.Password, passwordReset.Code);
    return Ok();
}

//in MyIdentityWrapperService
public async Task ResetPasswordAsync(string email, string password, string code)
{
    var userEntity = await _userManager.FindByNameAsync(email);
    var codeDecodedBytes = WebEncoders.Base64UrlDecode(code);
    var codeDecoded = Encoding.UTF8.GetString(codeDecodedBytes);
    await _userManager.ResetPasswordAsync(userEntity, codeDecoded, password);
}

A: I had a similar issue and I was encoding my token but it kept on failing validation and the problem turned out to be this : options.LowercaseQueryStrings = true;
Do not set true on options.LowercaseQueryStrings this alters the validation token's integrity and you will get Invalid Token Error.
// This allows routes to be in lowercase
services.AddRouting(options =>
{
     options.LowercaseUrls = true;
      options.LowercaseQueryStrings = false;
});

A: (according this post: https://stackoverflow.com/a/27943434/9869427)
For the resetPasswordAsync (identity manager) "token invalid" problem... because "+" become space in url...
use Uri.EscapeUriString
exemple: in my sendResetPasswordByMailAsync
var token = "Aa+Bb Cc";
var encodedToken = Uri.EscapeDataString(token);

encodedToken = "Aa%20Bb2B%Cc"

var url = $"http://localhost:4200/account/reset-password?email={email}&token={encodedToken}";
var mailContent= $"Please reset your password by clicking here.";

Now u can click on your link, and you will go to the good url with "+" (encode by %2B)... your token won't be invalid...

A: I had the same issue while hosting my website using Cloud Run in GCP, and none of the solutions here worked for me.
In my case the problem was with the data protection keys being stored locally in the instance. The following entry in the logs hinted the problem:

Storing keys in a directory '/home/.aspnet/DataProtection-Keys' that may not be persisted outside of the container. Protected data will be unavailable when container is destroyed.

Because of this, the tokens were only valid to the instance that issued them, which was already destroyed by the time the users clicked the link sent to their email.
The solution was to use a distributed storage for the keys, for instance, a database via EntityFramework:
using Microsoft.AspNetCore.DataProtection;
...
public void ConfigureServices(IServiceCollection services)
{
    services.AddDataProtection()
        .PersistKeysToDbContext<DbContext>();

    services.AddIdentity<User, IdentityRole>()
                .AddEntityFrameworkStores<AnotherDbContext>()
                .AddDefaultTokenProviders();
}

The details of the different types of storages can be found here.

A: Had a similar issue for ASP Core 2.1, and was scratching my head, because any encoding/decoding for code(token) did not work for me. And I always had an Invalid token error for userManager.ConfirmEmailAsync(user, code)

SOLUTION:
Turned out that the issue was that the user was created not with UserManager but using dbcontext like _dbContext.Users.AddAsync after replacing this creation method with _userManager.CreateAsync everything worked fine for me even without any encoding/decoding for code(token).

A: In my case, this problem was due to OnPostAsync method in RegisterModel encoding the callback url:
var callbackUrl = Url.Page(
                    "/Account/ConfirmEmail",
                    pageHandler: null,
                    values: new { userId = user.Id, code = code },
                    protocol: Request.Scheme);

await _emailSender.SendEmailAsync(Input.Email, "Confirm your email",
                    $"Please confirm your account by clicking here.");

This encoding (the application of HtmlEncoder.Default.Encode() to callbackUrl), made the url '&' become '&', thus invalidating the whole link.

A: You can also use regex when verifying the token in the reset put.
var decode = token.Replace(" ", "+");

await _userManager.ResetPasswordAsync(user, decode, Password);

redpajama_set_name: RedPajamaStackExchange


Cancer of the lung and bronchus currently ranks second among the top ten leading sites and causes of cancer incidence and death among Californians, according to the California Department of Health Services. It is particularly alarming that from 1988-1996 the average annual rate of death per 100,000 population from this disease is highest among African-Americans in California, where it exceeds that of all other races by 39%, i.e. 61 versus 44 per 100,000 population. We plan to produce a vaccine against human lung cancer for which we have already obtained a proof of concept in a mouse model, where we demonstrated that a vaccine against carcinoembryonic antigen (CEA), widely distributed among lung carcinoma patients can prevent the onset of this cancer. Our aim is to further improve the efficacy of this vaccine and to design it so that it can also be used to treat existing lung cancer and prevent its recurrence, particularly in a setting of minimal residual disease. In other words, our aim is to prevent, or at least slow down, the spread (metastases) of lung cancer in patients who were treated by other means, e.g. surgery, but still had some persisting lung cancer metastases. Our aim is to achieve this by using a genetically engineered vaccine to strongly stimulate the body's natural defense mechanisms, i.e. immunity against cancer cells. Since we are using a specialized mouse model system to evaluate our vaccine directed against an antigen, i.e. a molecular marker extensively expressed on human lung cancer cells, it is conceivable that our vaccine, once perfected in the mouse model, could rapidly enter clinical trials to critically evaluate its ability to treat human lung cancer in a minimal residual disease setting. Importantly, achievement of this research proposal's objectives may not only aid in improving prevention and treatment of lung cancer, but may also serve as a model for developing new and effective DNA vaccines against other cancers, including those of the colon, breast and pancreas.


A key organizer for max. 6 keys, 6 additional functions, bottle opener, carabiner, wrench (4 sizes), slotted screwdriver, a tool for wing screws, centimeter/inch ruler, incl. belt pouch, aluminum, stainless steel, matt, titanium/silver.


text:
Category: Detente
Archives Cold War Detente Soviet Era 1917-1991
"Brezhnev's hospitality was effusive, if unpredictable…"
Post author By Andrew Jenks
No Comments on "Brezhnev's hospitality was effusive, if unpredictable…"
The words in the title of this post come from a description by Donald M. Kendall, CEO of PepsiCo from 1971 to 1986. Kendall met Brezhnev in August 1973 in the Soviet Union and reported back on his meeting to Nixon and Henry Kissinger — who were both close to Kendall. Kendall — who had also played a critical role in the overthrow of the Allende regime in Chile — used those connections to penetrate the Soviet market during Nixon's detente and thus counter Coca Cola in the epic sugar water wars (Jimmy Carter was later close to Coca Cola and aided its penetration of the Chinese market in 1979). Kendall's enduring influence in Russia is suggested by his receipt in 2004 from Vladimir Putin of the Order of Friendship medal.
The result of Kendall's meeting with Brezhnev is a fascinating read: 15 typed pages of his observations of Brezhnev's personality, political inclinations, and endearing qualities — endearing, that is, for certain types of males who like sports, drinking, hunting, fishing, boating, and cars (Brezhnev's favorite was the iconic 1970s muscle car, the Dodge Charger).
The document below comes from the National Security Council, Henry Kissinger/Anatoly Dobrynin files at the Nixon Presidential Library and Archives in Yorba Linda, Ca. I came across them as part of my latest research project on international collaboration in space as a window into detente and the late Cold War. Soviet/American collaboration, leading to the Apollo-Soyuz Test Project of 1975, played a critical role in the creation and unfolding of Nixon's policies of detente (referred to as peaceful coexistence by the Soviets). While providing insight into Brezhnev and the Soviet political leadership, the document also illustrates the shared culture of male bonding and machismo on both sides of the Cold War divide.
Continue reading ""Brezhnev's hospitality was effusive, if unpredictable…""
Cold War Detente Soviet and Russian Space Flight Soviet Era 1917-1991
Hot-Tub Diplomacy and Star Wars
3 Comments on Hot-Tub Diplomacy and Star Wars
I've been reviewing documents from the Hoover Archives in connection with my latest project (http://russianhistoryblog.org/2011/10/transnational-history-and-space-flight/). The ones I've posted here, with brief commentary and historical context, concern an organization of astronauts and cosmonauts called the Association of Space Explorers, which held its first Congress in Paris in October 1985.
Aleksei Leonov and Deke Slayton on the Apollo-Soyuz Test Project
The idea for the group emerged during informal conversations between cosmonauts and astronauts dating back to the Apollo-Soyuz mission in 1975 — that "memorable handshake in space," as the world press at the time put it. The end of detente, however, got in the way, first with the Soviet invasion of Afghanistan, followed by the U.S. boycott of the Moscow Summer Olympics, the Soviet boycott four years later of the Los Angeles games, Reagan's announcement of the Star Wars program in March 1983, and the Soviet shooting down of a South Korean jet airliner in September 1983.
Continue reading "Hot-Tub Diplomacy and Star Wars"

redpajama_set_name: RedPajamaCommonCrawl


text:
Split-Ring Structured All-Inorganic Perovskite Photodetector Arrays for Masterly Internet of Things
Bori Shi1,
Pingyang Wang1,
Jingyun Feng1,
Chang Xue1,2,3,
Gaojie Yang4,
Qingwei Liao5,
Mengying Zhang6,
Xingcai Zhang4,5,
Weijia Wen3,7 &
Jinbo Wu1,2,3
Nano-Micro Letters volume 15, Article number: 3 (2023) Cite this article
The split-ring topography is studied systematically from wettability, evaporation assembly to optoelectronic devices.
An efficient dual-function laser etching scheme has been developed to fabricate the split-ring lyophilic pattern and the lateral electrode array simultaneously.
A non-contact human-machine interface based on CsPbBr3 perovskite photodetector arrays has been successfully applied to wearable devices, automobile displays, robot remote control.
Photodetectors with long detection distances and fast response are important media in constructing a non-contact human–machine interface for the Masterly Internet of Things (MIT). All-inorganic perovskites have excellent optoelectronic performance with high moisture and oxygen resistance, making them one of the promising candidates for high-performance photodetectors, but a simple, low-cost and reliable fabrication technology is urgently needed. Here, a dual-function laser etching method is developed to complete both the lyophilic split-ring structure and electrode patterning. This novel split-ring structure can capture the perovskite precursor droplet efficiently and achieve the uniform and compact deposition of CsPbBr3 films. Furthermore, our devices based on laterally conducting split-ring structured photodetectors possess outstanding performance, including the maximum responsivity of 1.44 × 105 mA W−1, a response time of 150 μs in 1.5 kHz and one-unit area < 4 × 10–2 mm2. Based on these split-ring photodetector arrays, we realized three-dimensional gesture detection with up to 100 mm distance detection and up to 600 mm s−1 speed detection, for low-cost, integrative, and non-contact human–machine interfaces. Finally, we applied this MIT to wearable and flexible digital gesture recognition watch panel, safe and comfortable central controller integrated on the car screen, and remote control of the robot, demonstrating the broad potential applications.
Intelligent perception and control through human–machine interaction often rely on the acquisition and processing of signals from acoustic, optical, electrical, and mechanical sensors [1,2,3,4,5,6]. Therefore, an intelligent, fast, and friendly interface is essential for information transmission and action execution between humans and machines, while humans often input signals into machines by pressing mechanical buttons or touching electronic screens, which makes mechanical wear and fatigue inevitable for interactive interfaces. Moreover, these physical contacts are very likely to become a medium for the transmission of bacteria, viruses, and harmful substances between different populations in special environments such as hospitals and laboratories. Consequently, non-contact sensors (such as photodetectors, humidity sensors, and electrostatic sensors) are becoming the development trend for human–machine interfaces [7,8,9,10,11]. Among them, photodetectors, which can convert optical signals into electrical signals, have been widely used in image sensing, optical communication, and other applications [12,13,14,15,16]. Non-contact optoelectronic interfaces, which are composed of photodetector arrays, perceive the motion of a distant object through shadow detection. Such devices have gradually become innovative human–machine interactions due to their advantages of long detection distances and fast response time.
Various types of optoelectronic materials have been reported to fabricate photodetectors in the past, such as silicon semiconductors, and organic polymer. But they usually have complicated structures and require high-temperature or complex fabrication processes, leading to high cost [17, 18]. Under the trend of miniaturization, arraying and flexibility of devices, simple and efficient fabrication processes can meet greater commercial needs. Metal halide perovskite materials, which are considered as suitable candidate for optoelectronic devices [19], due to their excellent optoelectronic properties, such as high carrier mobility and high absorption coefficients [20, 21]. Furthermore, compared with organic–inorganic hybrid perovskites, all-inorganic perovskites exhibit better long-term stability in the environment due to higher moisture and oxygen resistance [22,23,24,25,26]. However, the devices made of all-inorganic perovskite films perform inconsistently due to the difficulty associated with controlled nucleation and crystallization process [25, 27]. On the other hand, although many researchers have applied perovskite materials to miniaturized, arrayed and integrated photodetectors, including photoconductors [28,29,30,31,32], photodiodes [33,34,35,36], and phototransistors [37, 38], the geometric constraints of these optoelectronic material often require photolithography and mask thermal evaporation to complete patterning and arraying [39]. Therefore, the high cost and complex fabrication process have limited the wider commercial application of optoelectronic devices based on perovskite materials [40, 41].
In this study, we reported an all-inorganic CsPbBr3 split-ring structured photodetector (SRP) array for non-contact human–machine interaction (Fig. 1). We developed a dual-function laser etching scheme that can simultaneously complete the patterning of lyophilic layer and electrodes, which greatly reduced the cost and processing steps, and provided new insights into the preparation of laterally structured devices. In addition, we achieved the efficient directional transport of the perovskite precursor solution to the electrodes through a novel split-ring lyophilic pattern and realized the high crystallinity of CsPbBr3 perovskite films by reducing the deposition area by 62%. Finally, we applied a high-performance split-ring structured photodetector array to a non-contact human–machine interface for Masterly Internet of Things, achieving digital gesture recognition in a flexible wearable device and innovatively developing a three-dimensional (3D) gesture motion sensing scheme that is integrated into the display. This scheme allows humans to interact more flexibly with the intelligent system by using 3D gestures. We also successfully controlled a robot remotely through this interface, which verifies the multifunctional development potential of the device.
Schematic of CsPbBr3 photodetector array-based human–machine interaction process for MIT. a A schematic diagram of the structure of the human–machine interface. The device is composed of a packaging layer, a lyophilic layer, a perovskite film array, an electrode layer, and a substrate. b Schematic diagram of the split-ring structured perovskite photodetector. c Applications of device in human–machine interaction. d This durable and sterile interface versus the mechanical button with virus
Experimental Section
All chemical reagents were used as received and without further purification, including cesium bromide (CsBr, 99.9%, Aladdin Reagent, Shanghai, China), lead bromide (PbBr2, 99.9%, Aladdin Reagent, Shanghai, China), dimethyl sulfoxide (DMSO, 99.9%, Aladdin Reagent, Shanghai, China), and 1H,1H,2H,2H-Perfluorooctyltriethoxysilane (POTS, 98%) were purchased from Sigma-Aldrich, Co. Indium tin oxide-glass (ITO-glass, type: YK-ITO-Y11-10, ITO thickness: 180 nm, sheet resistivity: 10 Ω) was purchased from Suzhou ShangYang Solar Technology Co., Ltd.
Device Fabrication
Preparation Process of Lyophilic–lyophobic Pattern on the Substrate
ITO-glass was, respectively, ultrasonically cleaned in ethanol and deionized water for 5 min, and the surface of ITO-glass was further cleaned for 2 min with Plasma Cleaner (PDC-002-HP Plasma Cleaner) after it was fully dried. Lyophilic groups were generated on the treated substrate, which can increase the wettability of the substrate. The substrate and an open container containing 2 μL PTOS were placed in an airtight container with the oven (BINDER GmbH FD56) at 120 °C for 2.5 h. The surface of the substrate was covered with POTS molecular layer and had good lyophobic properties. Finally, the substrate was etched by nanosecond pulse laser (Bellin-SP350-10, repetition frequency 50 kHz, average power 1.045 W, and wavelength 355 nm) to form a lyophilic–lyophobic pattern array.
Fabrication of CsPbBr3 Array
PbBr2 and CsBr were dissolved in polar solvent DMSO at a molar ratio of 1:1, heated and dispersed ultrasonically by an ultrasonic cleaning machine (Elmasonic Easy 60 H) for 4 h to synthesize 0.4 mol L−1 CsPbBr3 precursor solution. The coating process used our independently developed device: the glass brush was placed vertically above the base at a height of 10 μm, the gap between the brush and the substrate was filled with 10 μL of precursor solution, and the coating was carried out at a uniform speed of 150 mm min−1 under the drive of the stepper motor. At this time, a high-throughput precursor array will be formed at the lyophilic pattern on the substrate. Subsequently, the substrate was quickly transferred to a heating plate (RCT Basic S025) at 60 °C, and the high crystallinity perovskite film array was formed by heating assisted evaporation of precursor droplets. The above process was completed in a glove box with an ambient temperature of 25 °C and a relative humidity of 30%. Finally, the samples were placed in a vacuum oven (BluePard DZF-6050) at 80 °C for 8 h to improve the crystal quality of perovskite films.
Fabrication of Photodetector Array Device
Several ITO conductive channels were formed on the surface of the substrate by laser etching. One end of the channel extended to the edge of the substrate to facilitate the connection of external circuits. The other end of the channel was connected to the gap in the split ring pattern, isolating the inside and outside of the pattern from each other, thus forming a lateral structure of the dual-electrode device.
Morphology and Structure Characterization
The intrinsic contact angles and surface adhesion energy of substrate with different surface properties were measured by contact angle analyzer (Kruss-DSA25). The dewetting and crystallization processes of microdroplet at high time resolution were captured by microscope (Olympus IX73) and high-speed camera (PHANTOM MIRO R311). The optical microscopic image of the CsPbBr3 film units and arrays were obtained by a microscope (LEICA DFC7000T). The confocal micrographs of fluorescein sodium salt/glycerol taken by laser scanning confocal microscope (Olympus FV3000). The morphology, element distribution and cross section profile of the etch lines on the substrate surface and CsPbBr3 films were, respectively, characterized by field emission scanning electron microscopy (Hitachi, SU-8230), energy dispersion spectrometer (OXFORD Ultim Extreme) and surface profilometer (Alpha-Step D-300), respectively. X-ray diffraction spectrum of CsPbBr3 were obtained using X-ray diffractometer (PANalytical Empyrean Alpha 1).
Optical and Optoelectronic Characterization
The absorption and photoluminescence spectrum of CsPbBr3 films were, respectively, measured by UV–Visible absorption spectrometer (PERKIN-ELMER Lambda750) and fluorescence spectrometer (Edinburgh FS-5 UK); the fluorescence lifetime of CsPbBr3 films at excitation wavelength of 365 nm was measured by time-resolved fluorescence spectrophotometer (Edinburgh Photonics Mini-Tau). The performance of the photodetectors was characterized by a customized testing platform and all the tests were carried out in ambient condition. We use an arbitrary waveform generator (TeKtronix AFG3251C) as a voltage source to control the LED lamp (CREE XPE2) and laser lamp (Thorlabs CPS532). The light power density is calibrated by power meter (Newport 843-R). The voltage ampere characteristic curve of the photodetectors was tested with semiconductor parameter instrument (Keithley 4200). The response time and stability of the photodetector were tested with oscilloscope (KEYSIGHT DSOX1202A). A data acquisition system (multifunctional I/O device NI PCI-6259 and junction box NI SCB-68A) was used to measure the photocurrent value of the photodetector array in multi-channel real-time.
Mechanism of Split-Ring Topography-Assisted Dewetting
A schematic diagram of the perovskite array preparation process is shown in Fig. 2a, lyophilic patterning by laser etching on a lyophobic substrate modified by 1H,1H,2H,2H-perfluorooctyltriethoxysilane (POTS), sliding the perovskite precursor solution, and evaporation self-assembly of the crystalline film. Among these steps, the lyophilic–lyophobic patterning of the substrate is a key step for the preparation of perovskite film arrays. This pattern can assist the generation of the droplet array and the efficient directional transport of precursor solution by dewetting, ensuring the dense and uniform deposition of particles in the perovskite film.
a Schematic diagram of the preparation process of the photodetector array based on the split-ring structured perovskite film. b The perovskite precursor solution dewetting processes captured by a high-speed camera (blue and red arrows indicate surface tension and pinning force, respectively, scale bar: 50 μm). c Themorphology of a glycerol split-ring droplet taken by Confocal microscope after dewetting process (scale bar: 80 μm). d The evaporation process of precursor solution captured by a high-speed camera on the hot plate (scale bar: 50 μm). e–g The dewetting and deposition results of a fully lyophilic square pattern, a square ring pattern without opening, the split-ring pattern, and a trilateral pattern (scale bar: 100 μm)
Discontinuous dewetting refers to the process in which the solid–liquid interface is discontinuously replaced by the solid–gas interface, which is often employed during the liquid coating on the lyophilic–lyophobic patterned substrate to generate droplet arrays in a high-throughput manner [42, 43]. In this dewetting process, a split-ring-structure lyophilic pattern assisted the droplet unit to dewet again inside the pattern, to achieve the directional transport process of the precursor solution. The outer boundary and the gap of the pattern determined the first and second dewetting processes. We recorded these two rapid dewetting processes using CsPbBr3 precursor solution captured by a high-speed camera (Fig. 2b and Video S1). Under the external force, the advancing mother-solution continuously wetted and dewetted on the substrate until the retreated three-phase contact line (TCL) met the boundary of the pattern, and solution was pinned by the lyophilic surface to form a liquid bridge. The liquid bridge gradually became thinner and narrower under the continuous pulling until it broke up in an instant to leave a son-droplet in the lyophilic pattern (Fig. 2biv).
The time intervals of Fig. 2bi to 2bii and Fig. 2bii to 2biii are both 0.5 ms. It is worth noting that a small satellite droplet first appeared in the liquid bridge in Fig. 2bii, which indicated that the liquid bridge was breaking up at this moment. When the liquid bridge broke up, the TCL shrank along the outer boundary of the lyophilic pattern and contacted the lyophobic gap. This split-ring structured liquid film was in a metastable stage due to the imbalance between the pinning force and surface tension (Fig. 2biii). Therefore, the TCL of the liquid film retracted continuously to the lyophobic interior of the split-ring pattern and became a droplet, which manifested as the second dewetting process (Fig. 2biii to 2biv, 2 ms). The static contact angle between the CsPbBr3 precursor solution and the POTS-modified substrate was approximately 84° ± 3°, and the laser-etched area was 26° ± 4°, indicating that the wettability of the substrate surface differed significantly before and after laser etching (Fig. S1).
To prove that the second dewetting process was spontaneous, we calculated the adhesion energy between the solvent dimethyl sulfoxide (DMSO) and the regions with different wettability on the substrate. In our experiment, the adhesion energy ISL was calculated with the Fox equation:
$${I}_{SL}=2[({\sigma }_{L}^{D}{)}^{1/2}({\sigma }_{S}^{D}{)}^{1/2}+({\sigma }_{L}^{P}{)}^{1/2}({\sigma }_{S}^{P}{)}^{1/2}]$$
wherein \({I}_{SL}\) is the adhesion energy between a liquid and a solid surface per unit area, \({\sigma }_{L}^{D}\) is the dispersive component of the surface tension of the wetting liquid, \({\sigma }_{L}^{P}\) is the polar component of the surface tension of the wetting liquid, \({\sigma }_{S}^{D}\) is the dispersive component of the surface energy of the solid, and \({\sigma }_{S}^{P}\) is the polar component of the surface energy of the solid. This equation uses a dispersion component and a polar component to describe the surface energy of a solid. The adhesion energy in the lyophobic region was calculated to be 51.8 mN m−1. The lyophilic region was the trench region of ITO etched by laser, with an adhesion energy of 95.9 mN m−1. Therefore, the adhesion force of the lyophilic zone to the DMSO was greater than the lyophobic one, which supported the claimed ability of the second dewetting process to occur inside the split-ring pattern. A more detailed formula derivation process and relevant data are shown in Table S1.
To characterize the 3D structure of the split-ring droplet, the 3D images of the droplet after dewetting were taken by laser confocal scanning microscopy (LCSM). We chose 40 wt% glycerol instead of DMSO as the solvent to avoid quick evaporation during optical sectioning. Detailed properties of glycerol and DMSO can be found in Table S2. The 3D projection, vertical and cross-sectional views of glycerol droplet dyed with fluorescein sodium salt are shown in Fig. 2c. This split-ring structured droplet can be viewed as a connected liquid puddle of a large droplet, crossing the lyophilic and lyophobic regions and forming a high local contact angle, and two extended liquid films on the lyophilic region forming a small local contact angle.
The deposition process of our split-ring patterned liquid could be affected by multiple mechanisms. Figure 2d and Video S2 showed the evaporation and self-assembly crystallization process of the precursor droplet array at 60 °C and 30% humidity under high-speed imaging. The first stage of this process occurred during the initial stage of heating, when the substrate temperature gradually increased, the TCL of the large droplet steadily retracted to the lyophilic region. In the second stage, the precursor droplets reached the critical concentration for nucleation, and then gradually precipitated perovskite crystal nuclei and nanoparticles. Due to the pinning of the lyophilic pattern on the droplet, the TCL of the droplet could not contract further at this time. With the continuous evaporation of the solvent by heating, the shrinkage rate of the gas–liquid interface of the solution film exceeded the average diffusion rate of the perovskite nanoparticles, and the precipitated nanoparticles were captured by the rapidly dropping gas–liquid interface, forming a semisolid layer with a uniform grain distribution. After the solvent had completely evaporated, a dense deposition of particles in the perovskite film was achieved. Figure S2 further compared and discussed the evaporation mechanism and the crystal deposition morphology of the split-ring pattern under room temperature and heating conditions.
To further study the dewetting dynamics, we compared the dewetting and deposition results of four lyophilic patterns with similar outer contours including a fully lyophilic square pattern, a square ring pattern without opening, the split-ring pattern, and a trilateral pattern in Fig. 2e–g. Meanwhile, their dewetting processes, confocal micrographs and evaporation processes are shown in Figs. S3-S5. The confocal micrographs reflect the three-dimensional topography of those four patterns. The liquid volume of those four patterns are calculated by stacking the sectional images. The droplet volumes of the fully lyophilic square, the square ring, the split-ring and the trilateral pattern are 3.4, 3.4, 2.8, and 0.9 nL, respectively. Compared to the fully lyophilic and square ring patterns, the split-ring pattern can maintain 82% amount of liquid. The crystallized film from the fully lyophilic square pattern with a large deposition area shows poor compactness (Fig. S6). Due to the interior of the square ring pattern is lyophobic, liquid film rupture or dewetting may occur during evaporation, resulting in a random deposition. With the lyophilic topography structure changing from ring to split-ring, the deposition area is reduced greatly to 38% of the whole pattern (that is lyophilic area) while droplet volume maintained almost the same. To explore the influence of split-ring structure, the deposition results of square and circular rings with different gap widths and diameters or side lengths are shown in Fig. S7. Through the optimization and comparison, we conclud that the split-ring structure with a length and gap of approximately 200 and 30 μm can achieve the best compactness of the perovskite film by surface capturing of the droplet without any passivation agent or spatial template, which provides a prerequisite for the excellent optoelectronic performance of the device.
High-Throughput Fabrication of Split-ring-structure Perovskite Arrays
Here, a dual-function laser etching method is proposed for the one-step fabrication of the patterned lyophilic–lyophobic surface and electrode array on the substrate, then the split-ring pattern is used to deposit the perovskite film on the ITO dual-electrodes. A schematic diagram of the mechanism of laser etching is shown in Fig. 3a. The YZ plane shows the typical Gaussian distribution of the intensity of the laser beam (note: the energy increases down the Z-axis), and the XY and XZ planes show the 3D and cross section of the laser-etched substrate severally. When a Gaussian laser beam acts on the surface of the substrate, the energy at the center of the laser spot is sufficiently intense to vaporize the ITO electrode layer; at the same time, the edge of the laser spot reduces the lyophobic effect of the adjacent POTS layer through a photothermal effect, forming a heat-affected zone. Interestingly, due to the width of the heat-affected zone is always significantly larger than that of the etched zone, the area that can be wetted by the precursor solution can completely cover the ITO trench. The perovskite film with densely packed particles can cross the two sides of the trench from ITO etching laterally to form a dual-electrode device after evaporation and crystallization (Fig. S8b and the top of Fig. 3b). The depth of the ITO trench by laser etching is 180 nm, which is consistent with the thickness of the ITO film. The schematic diagram and result of the surface profile test are shown in Fig. S8a and the bottom of Fig. 3b, respectively. In addition, the surface height after perovskite deposition is approximately 600 nm, and the perovskite film completely cover both sides of the trench from ITO etching. Figure S9 depicts the effect of laser power density on the etching width of the ITO and POTS. As the laser power density increases, the thermal effect at the laser spot also enhences. The use of excessive laser power density will cause damage to the glass substrate and produce a melting zone of ITO, resulting in a rough surface. In contrast, the use of insufficient laser power density cannot fully evaporate the ITO conductive layer, resulting in the failure of the ITO dual-electrodes. Therefore, we found a appropriate laser not only to effectively etch the ITO conductive layer but also to thermally vaporize the relatively wide POTS lyophobic layer, which is conducive to the effective deposition of perovskite films.
a Schematic diagram of the mechanism of laser etching. The XY and XZ planes showed the 3D and cross-sectional views of the etching effect, respectively. The YZ plane showed the Gaussian distribution of the laser beam intensity. b The cross section SEM image of the perovskite-deposited ITO-glass. The surface profile of the ITO-glass after laser etching and the perovskite-deposited ITO-glass shown in the bottom graph. c An optical image of the perovskite film array patterned as "SHU" on the glass substrate (scale bar: 1 cm). The inset showed the SEM image of part of the perovskite array (scale bar: 600 μm) and enlarged view of film (scale bar: 1 μm). d The top and bottom pictures severally were SEM and EDS mapping images of the substrate before (left) and after (right) perovskite deposition. The scale bar is 8 μm. e XRD spectra of the perovskite array. f The PL and absorption spectra of CsPbBr3. The inset showed the spectrum for calculating the optical band gap. g A time-resolved PL spectroscopy curve of the CsPbBr3 arrays
The letters "SHU" are composed of an array of split-ring structured perovskite films, and the insets show locally zoomed-in SEM images of the array (Fig. 3c). The area of perovskite unit less than 200 μm2, at this array density, a 1 cm2 substrate can accommodate 900 units. The average transmittance of the sample in the visible light range exceeds 83% (Fig. S10). The excellent optical transparency of the perovskite array allows it to be easily integrated on the surface of glass or screen and to act as a display without blocking the background image, which further expands the application of transparent sensors. In Fig. 3d, the major elemental distribution on the etched line are Si and O, while outside the etched line are In and Sn, indicating that the etched area is the exposed glass substrate due to the complete vaporization of the ITO layer in this area. Cs, Pb, and Br are uniformly distributed in the deposited crystalline film, and the perovskite film completely cover both sides of the trench from ITO etching. This result is in perfect agreement with the surface profile data in Fig. 3b. The CsPbBr3 film after annealed at 80 °C exhibit evident double diffraction peaks at 15° and 30° in X-ray diffractometer (XRD) spectrum (Fig. 3e). In addition, the characteristic peak of In2O3 in the cubic crystal orientation can be clearly observed at 35.5°, indicating that no foreign impurities are introduced during the entire preparation process. The absorption, photoluminescence (PL) and calculated optical band gap spectrum of the CsPbBr3 perovskite film in Fig. 3f show an absorption cutoff at ≈ 540 nm and the bandgap is calculated about 2.3 eV. The perovskite exhibits a photoluminescence (PL) emission peak at ≈ 530 nm with a full width at half maximum of ≈ 25.8 nm suggests a high color purity. The carrier lifetime can be calculated by measuring the fluorescence kinetic parameters of the CsPbBr3 film. After double exponential fitting of the fluorescence decay curve, the short lifetime τ1 is 0.949 ns and the long lifetime τ2 is 11.213 ns of the CsPbBr3 film, which correspond to the surface recombination and bulk recombination of electrons and holes after excitation (Fig. 3g).
Photoelectric Properties of CsPbBr3 Split-ring-structure Photodetector
Compared with the vertical structure, the lateral structure has advantages of easy preparation and integration in dual-electrode devices. Laser etching is used to close and appropriately extend the split-ring area where ITO is etched under the perovskite film to form two independent ITO electrodes inside and outside the pattern. The working mechanism diagram of the SPR and partial enlargement is shown in Fig. 4a–b. In contrast to the traditional symmetric electrode structure, the photogenerated current of this photodetector flows laterally inside and outside the pattern, and the conduction distance is only the width of the laser-etched area. This conduction mode greatly narrows the current transmission distance and fully utilizes the perovskite photoactive layer. Figure 4c shows the energy-band alignment of the photodetector. Under irradiation, the CsPbBr3 crystal generates electron–hole pairs, which are collected by the ITO electrodes at both ends under the driving force of an external bias voltage to form a photogenerated current. Since the photogenerated carriers will drift under a bias voltage and the drift velocity of the carriers is proportional to the magnitude of the photocurrent, the photocurrent of the device increases as the applied bias voltage increases (Fig. 4d). Figure S11 shows the current–voltage (I–V) curves of the photodetector measured under dark and a light intensity of 10 mW at 520 nm. The maximum on/off ratio and the dark current of this device measured at 2.3 V are 8.2 × 103 and 2.03 × 10–11 A, respectively. Figure 4e presents the I–V curves of the photodetector under 450 nm irradiation with different light intensities. Due to the Schottky barrier at the contact interface between the CsPbBr3 perovskite film and the ITO electrode, all the curves exhibite asymmetric rectification. Under the same bias voltage, the number of photogenerated carriers is proportional to the absorbed photon flux. Therefore, increasing the light intensity can increase the number of photons incident on the CsPbBr3 perovskite film, resulting in an increase in the photocurrent. Responsivity refers to the ratio of the photocurrent to the light intensity of the photodetector under irradiation of a specific wavelength and represents the photoelectric conversion efficiency of the photodetector. Responsivity (R) can be expressed as follows:
Photodetection performance of individual perovskite photodetector on a glass substrate. a Schematic diagram of the lateral structure and working mechanism of an SRP. b Schematic diagram of partial enlargement of SRP. c The energy-band alignment of SPR. d Current–time (I–t) curves of the perovskite photodetector under different bias voltages when irradiated with a 450 nm pulsed light source. e I-V curves of the photodetector under the irradiation of a 450 nm light source at different light powers. f Dependence of the responsivity, the D* and the photocurrent on the light intensity at the 520 nm. g A normalized responsivity curve of the photodetector under different illumination wavelengths (350 – 700 nm). h I-t curves at a 6 V bias and different on/off frequencies of 520 nm light sources. i On/off switching stability test of the device at a 3 V bias and 520 nm pulsed light source at a frequency of 0.05 Hz
$$R=\frac{({I}_{light}-{I}_{dark})}{PS}$$
where Ilight and Idark represent the light and dark current of the photodetector, respectively; P represents the light intensity of the light source, and S is the active area of the photodetector (1.38 × 10–2 mm2). The detection sensitivity of a photodetector to light is usually expressed as the specific detectivity (D*), which could be calculated by the following equation (assuming that the noise limiting the detectivity is major contributed by shot noise from the dark current [52]):
$${D}^{*} = \frac{R}{{(2e{I}_{dark}/S)}^{1/2}}$$
where e is the elementary charge (1.602 × 10–19 C). Figure 4f shows the response of the photocurrent (Ilight–Idark) and the responsivity and specific detectivity of the photodetector to different light intensities of a 520 nm light source at a 6 V bias. Due to the high crystallinity and compactness of the SRP, the photocurrent can be effectively collected by the electrodes, allowing a relatively large photocurrent to be generated under low light intensities. Furthermore, R decreases at a higher incident light intensity because more charge recombination is expected in this case [31]. Therefore, the peak responsivity reaches 1.44 × 105 mA W−1 at 0.56 μW cm−2, and the peak specific detectivity reaches 2.16 × 1011 Jones. Figure 4g shows the normalized responsivity curve of the photodetector in the range of 350–700 nm under a 3 V bias. This photodetector has a good responsivity to a light source from 350–530 nm. The responsivity peaks at approximately 520 nm and then decreases with increasing wavelength. This trend is consistent with the absorption spectrum because the CsPbBr3 film has a reduced absorption efficiency for photons with a long-wavelength. To evaluate the ability of the photodetector to track the optical signal, the normalized I–t curves is obtained by the photodetector under irradiation with 520 nm pulsed light at optical switching frequencies of 1 Hz, 200 Hz, and 1.5 kHz (Fig. 4g). With the on/off switching of the pulsed light source, the photodetector can quickly and accurately detect the changes in the optical signal and can subsequently generate a pulsed current with the same frequency. As shown in Fig. S12, the − 3 dB cutoff frequency (f − 3 dB) of the device is greater than 1.5 kHz. The response speed refers to the relaxation time needed for the photodetector to convert the incident light signal into a current signal. The time required for the photocurrent to increase from 10 to 90% and the time required for the photocurrent to decrease from 90 to 10% are usually defined as the rise time (trise) and fall time (tdown) of the photodetector, respectively. The trise and tdown of the photodetector were 151 and 135 μs in 1.5 kHz, respectively, both of which far exceed the speed of human perception of optical signal. The photodetector is continuously irradiated with pulsed light to investigate its stability and reversibility under air condition (3 V, Fig. 4i). The decay of the device packaged by PDMS is shown in Fig. S13. Due to the natural resistance of the all-inorganic perovskite CsPbBr3 film to environmental moisture and oxygen, the device's stable and reversible photoswitching characteristic. Table 1 summarizes and compares the key parameters of the reported perovskite photodetector arrays and the tested conditions and more information refer to Table S3. By comparison, our SRP is ranked highly in terms of its preparation process, responsivity, response time, and detectivity. The excellent comprehensive optoelectronic performance of SRP makes it suitable for mobile detection with rapid changes in optical signals.
Table 1 Comparison of key parameters of SPR with reported arrayable photodetectors
Applications of Photodetector Array in Non-contact Human–Machine Interaction
Figure 5A shows a photograph of the flexible wearable device. A polyethylene terephthalate (PET) flexible film was used as the substrate of the device, which provided the device with excellent transparency and appropriate stiffness so that the device can work stably on the curved surface like a smart watch. We integrated external circuitry for data acquisition on the back of the silicone strap, inserted the metal probe into the custom-made watch case, connected the probe with the flexible interface inside the case through a good electrical contact, and finally insulated and fixed the connection with polyimide tape. Figure S14 shows the current of the flexible device at different bending angles. This device can maintain a relatively stable photoelectric properties at a certain bending angle, so the use of the device is not affected in a fixed-angle scenario (such as curved-screens and wearable devices). Figure S15 shows the SEM image of the split-ring structured perovskite film on the ITO–PET substrate, and the crystalline film is still of high quality, which fully demonstrates the universality of the preparation method. A segment code liquid crystal display (LCD) display generally uses the visible states of seven-line segments to represent the numbers 0 to 9. Owing to this display method has simple programming and low power consumption, it has been widely used in LCD digital displays. According to the display mode of the segment code LCD displays, a total of six connection points or corner points are generated between the seven-line segments to express characters of any number. Hereby, we can determine the movement of the finger by detecting the spatiotemporal series in the photocurrent of the photodetector array, and the circuit diagram of this interface is shown in Fig. S16. Figure 5b shows the input gestures for "1" and "2" and the corresponding current data of the photodetector array. When a person writes numbers on the wearable device, the current of the photodetector decreases rapidly due to the shading of the finger. As the finger continues to move, the shadow leaves the photodetector site, and the photon irradiation causes the photodetector to rapidly recover to the initial current level. By using valleys in the I-t curve of the six photodetector units to judge gesture actions, which is beneficial to reduce data errors generated by other photodetector sites during the writing process. The SRP array spacing is 1.5 cm, this suitable spacing makes the writing gesture more comfortable for humans and can improve the accuracy of input signals. By writing the numbers "0, and 3–9," the measurement program of the photodetector can obtain the changes in the current data of different time series (Fig. S17). The realization of this function will help humans to input more instructions and information on the human–machine interface.
Application of the SPR array for non-contact human–machine interaction in flexible wearable devices and integrated 3D gesture detection. a The photograph of the flexible wearable device. b Gesture writing of the numbers "1" and "2" and the corresponding current. c The 3D gesture detection of the human–machine interface on the integrated car screen. d Schematic diagram of the detection mechanism of 3D motion detection and the current with the distance between the human hand and the display under a 5 V bias. e The current for different gestures at a 5 V bias
The automobile has greatly changed the way that people travel, and the car display has become an important branch of human–machine interaction. The operation interface of the automobile is designed to focus on the safety of the driver. We have innovatively developed a photodetector array-based 3D gesture detection scheme (Fig. 5c). By integrating a transparent device with the car display of the automobile, human can use simple touchless gestures during driving to achieve safe and comfortable interactions with the car. This interactive system can realize the recognition of 2D swiping gestures (for instance, swiping up and right are defined as page-up and next screen, respectively) and even 3D gestures (for instance, moving inward along the normal line of the screen is defined as "enter"). Figure 5d illustrates the application of the interactive system on 3D gestures motion in different driving environments, including day-time and night-time by testing the current data corresponding to different distances between the hand and the screen. Figure S18 shows a photograph of this test platform. When the hand approaches the device from a far distance, the current of the photodetector shows a gradually increasing trend. The current increases when the hand is 120 mm away from the screen and reaches its peak value when the hand is 20 mm from the screen. The current increased by 7.65% under the day-time and by 7.43% under the night-time driving condition, indicating that this device has high spatial perception and sensitivities under different lighting conditions. The detection mechanism of the 3D gesture is shown in the inset of Fig. 5d. A portion of the photons emitted by the display will be directly incident on the device so that the photodetector reaches a stable photocurrent level, and the remaining large number of photons will pass through the transparent substrate of the photodetector and radiate outward. When the human hand approaches the display, the skin surface will diffusely reflect the light. The photons reflected by the skin are irradiated to the photodetector, and further increasing the current. At the night-time, current growth rate is equivalent to that in the day-time driving, due to the reduction in the number of ambient light sources still helps to improve the response of the photodetector to the light reflected by the hand surface. Figure 5e shows the current data of the gestures of moving upward, forward and left, and refer to Fig. S16 for the circuit diagram of the system. The sequence that the current reaches its peak value can be used as the spatiotemporal series for determining the direction of the gesture movement. After the gesture passes through the photodetector array, the movement direction of the gesture can be perfectly matched based on the graphs, which demonstrates the 3D motion sensing capability of the integrated non-contact human–machine interface and provides a new insight into the sensing display-integrated multifunctional interactive system.
Our photodetector-based interactive system is expected to enable more interactive functions between humans and machines, instead of only signal input and information transmission. In many application scenarios (such as automated factories that require high-temperature reactions, laboratories that store corrosive reagents), direct contact between the operator and the machine should be avoided as much as possible. Figure 6a schematically depicts a scenario of a factory, in which humans can control the robot in real time through a touchless system. Figure 6b shows a schematic diagram of the circuit setup of the system. This construction is divided into three parts: the external circuit connection of the photodetector array, the acquisition and processing of real-time data, and the remote Ethernet control of the robot. We use a 4 × 4 array of photodetectors helps to improve the accuracy of program judgment and the complexity of operating commands. The sequence and interval of the shading of different photodetector units can be mapped to the movement direction and speed of the hand shading the photodetector. Hence, when the current drops below the threshold, the program will record and logically determine the identifier number of the photodetector unit, and then will output the data as the control command code that can be recognized by the robot controller. The real-time remote control of the robot must be completed by using LabVIEW as the client of the transmission control protocol (TCP) to send the control command code to the TCP server in the robot. We obtain on/off current data for 16 photodetector units under illumination by light-emitting diode (LED) and hand shaded (2 cm from the photodetector), respectively (Fig. S19). The standard deviations of the current and dark current of the photodetector arrays are 9.02 × 10–8 and 1.16 × 10–8, and the average on/off ratio is approximately 13.06, which can effectively reduce the program judgment errors. Figure 6c1 shows the manipulation of the sample grasping orientation by the robot through gestures. First, a human uses the swiping-up gesture from the bottom row of the photodetector array (4, 8, 12, 16) to the top row (1, 5, 9, 13). With the movement of the hand, the photodetector is exposed to the light source again. The real-time photocurrent variations are shown in Fig. 6c2. The current in each column drops almost simultaneously, while the current in each row gradually decreases. Figures 6d1-2 shows a robot performing sample transfer under remote control. When the hand laterally swipes over the photodetector array, the current in each column gradually decreases, while the current in each row changes simultaneously. The human–machine interaction process described above, including the robot's picking and transferring of targets, is shown in Video S3. The non-contact control process is accurate and fast, taking full advantage of the unique advantages of this system. Figure 6e demonstrates the speed detection function of the human–machine interface. A bare right hand and a gloved left hand move at different speeds in front of a row of photodetector arrays. Gestures with different movement speeds (V1-V4) are detected using two measurement methods, namely imaging-based measurement (Mi) and photodetector-based measurement (Mp). The detection mechanism of the imaging-based measurement method is to record the number of video frames corresponding to the gesture at different mark positions and convert the number of frames into time to calculate the movement speed of the gesture. The movement speeds measured by this method were Vi1 = 30.2 mm s−1, Vi2 = 109.2 mm s−1, Vi3 = 240.4 mm s−1, and Vi4 = 600.0 mm s−1. The speeds measured by the photodetector-based measurement method were Vp1 = 34.9 mm s−1, Vp2 = 128.5 mm s−1, Vp3 = 227.8 mm s−1, and Vp4 = 620.7 mm s−1. The speeds detected by the two methods are approximately the same. The current curves and the corresponding real-time video records at different gesture speeds verify the extremely high sensitivity and accuracy of the photodetector-based human–machine interface in the speed detection of moving objects (Fig. 6f and Video S4). To further compare the existing touchless gesture detection technologies, we summary the key sensor parameters of these technologies in Fig. 6g [7, 8, 10, 11, 53,54,55,56]. The photodetector-based interface we developed is superior in transparency, flexibility, detection distance, and response speed.
Remote control of robot based on gesture interaction. a The schematic diagram of the non-contact human–machine interaction scenario. b The schematic of the human–machine interactive system, including the construction of the photodetector array, real-time data acquisition and processing, and remote Ethernet control. c1-2 The robot's picking up process. d1-2 The robot's transfer process. e The schematic diagram of the real-time detection of gestures at different moving speeds by the device. f I-t curves of photodetector arrays at a series of moving speeds. g Comparison of sensor parameters of our device with reported sensor array for non-contact gesture detection
In summary, we studied systematically the split-ring topography from wettability, evaporative assembly to optoelectronics. The split-ring lyophilic patterns and electrode arrays were fabricated by a dual-function laser etching technique simultaneously. Compared to the fully lyophilic and square ring patterns, the split-ring pattern can capture 82% of precursor solution while the deposition area was reduced to 38%. This scheme not only assisted the highly efficient directional transportation of liquid, high-throughput fabrication of perovskite arrays and high compactness of perovskite film, but also simplified the preparation process and reduced the cost of the devices. Due to the high compactness and excellent optoelectronic properties of the split-ring structured, the photodetector we developed has the maximum responsivity reached 1.44 × 105 mA W−1, the maximum on/off ratio reached 8.2 × 103, and the response time reached 150 μs in 1.5 kHz.
We successfully implemented the human–machine interaction, including writing numbers, gesture detection, in scenarios such as wearable devices, automobile displays and remote control, fully demonstrating the potential of our non-contact scheme based on photodetector arrays in various environments. However, in practical applications, gesture detection is affected by many factors, such as the position of the light source, personal gesture habits, reflections or shadows of other objects, and so on. Therefore, further development of artificial intelligence assisted, or trained signal analysis software is necessary to reduce misjudgment and obtain an accurate spatiotemporal series. Moreover, the lyophilic-lyophobic patternsassisted dewetting approach enables a new fabrication technology with high-throughput of large-scale split-ring array. Given the featured size in the samples, the split-ring meta-structure can be readily developed into terahertz metamaterials [57,58,59]. Therefore, our results will also hold the promising application toward the structural design and preparation of metamaterials and their active application in the field of terahertz metamaterials.
D. Kim, N. Lu, R. Ma, Y. Kim, R. Kim et al., Epidermal electronics. Science 333(6044), 838–843 (2011). https://doi.org/10.1126/science.1206157
K. Qin, C. Chen, X. Pu, Q. Tang, W. He et al., Magnetic array assisted triboelectric nanogenerator sensor for real-time gesture interaction. Nano-Micro Lett. 13, 51 (2021). https://doi.org/10.1007/s40820-020-00575-2
A. Chorots, J. Liu, Z. Bao, Pursuing prosthetic electronic skin. Nat. Mater. 15(9), 937–950 (2016). https://doi.org/10.1038/nmat4671
Z. Zhou, K. Chen, X. Li, S. Zhang, Y. Wu et al., Sign-to-speech translation using machine-learning-assisted stretchable sensor arrays. Nat. Electron. 3(9), 571–578 (2020). https://doi.org/10.1038/s41928-020-0428-6
J. Kim, A.S. Campbell, B.E.F. Avila, J. Wang, Wearable biosensors for healthcare monitoring. Nat. Biotechnol. 37(4), 389–406 (2019). https://doi.org/10.1038/s41587-019-0045-y
J. Yi, K. Dong, S. Shen, Y. Jiang, X. Peng et al., Fully fabric-based triboelectric nanogenerators as self-powered human-machine interactive keyboards. Nano-Micro Lett. 13, 103 (2021). https://doi.org/10.1007/s40820-021-00621-7
L. Lu, C. Jiang, G. Hu, J. Liu, B. Yang, Flexible noncontact sensing for human-machine interaction. Adv. Mater. 33(16), 2100218 (2021). https://doi.org/10.1002/adma.202100218
S. An, H. Zhu, C. Guo, B. Fu, C. Song et al., Noncontact human-machine interaction based on hand-eesponsive infrared structural color. Nat. Commun. 13, 1446 (2022). https://doi.org/10.1038/s41467-022-29197-5
Y. Lu, G. Yang, Y. Shen, H. Yang, K. Xu, Multifunctional flexible humidity sensor systems towards noncontact wearable electronics. Nano-Micro Lett. 14, 150 (2022). https://doi.org/10.1007/s40820-022-00895-5
Z. Li, W. Ran, Y. Yan, L. Li, Z. Lou et al., High-performance optical noncontact controlling system based on broadband PtTex /Si heterojunction photodetectors for human–machine interaction. InfoMat 4(1), e12261 (2021). https://doi.org/10.1002/inf2.12261
Y. Tang, H. Zhou, X. Sun, N. Diao, J. Wang et al., Triboelectric touch-free screen sensor for noncontact gesture recognizing. Adv. Funct. Mater. 30(5), 1907893 (2019). https://doi.org/10.1002/adfm.201907893
C. Bao, W. Xu, J. Yang et al., Bidirectional optical signal transmission between two identical devices using perovskite diodes. Nat. Electron. 3(3), 156–164 (2020). https://doi.org/10.1038/s41928-020-0382-3
Y. Kim, K. Kim, D. Son, S. Bai, P. Teng et al., Printable organometallic perovskite enables large-area, low-dose X-ray imaging. Nature 550(7674), 87–91 (2017). https://doi.org/10.1038/nature24032
Q. Chen, J. Wu, X. Ou, B. Huang, J. Almutlaq et al., All-Inorganic perovskite nanocrystal scintillators. Nature 561(7721), 88–93 (2018). https://doi.org/10.1038/s41586-018-0451-1
X. Xu, W. Deng, X. Zhang, L. Huang, W. Wang et al., Dual-band, high-performance phototransistors from hybrid perovskite and organic crystal array for secure communication applications. ACS Nano 13(5), 5910–5919 (2019). https://doi.org/10.1021/acsnano.9b01734
W. Ran, L. Wang, S. Zhao, D. Wang, R. Yin et al., An integrated flexible all-nanowire infrared sensing system with record photosensitivity. Adv. Mater. 32(16), e1908419 (2020). https://doi.org/10.1002/adma.201908419
C. Li, Y. Ma, Y. Xiao, L. Shen, L. Ding, Advances in perovskite photodetectors. InfoMat 2(6), 1247–1256 (2020). https://doi.org/10.1002/inf2.12141
H. Wang, S. Li, X. Liu, Z. Shi, X. Fang et al., Low-dimensional metal halide perovskite photodetectors. Adv. Mater. 33(7), e2003309 (2021). https://doi.org/10.1002/adma.202003309
A. Breemen, R. Ollearo, S. Shanmugam, B. Peeters, L.C.J.M. Peters et al., A thin and flexible scanner for fingerprints and documents based on metal halide perovskites. Nat. Electron. 4(11), 818–826 (2021). https://doi.org/10.1038/s41928-021-00662-1
Z. Yang, M. Wang, H. Qiu, X. Yao, X. Lao et al., Engineering the exciton dissociation in quantum-confined 2D CsPbBr 3 nanosheet films. Adv. Funct. Mater. 28(14), 1705908 (2018). https://doi.org/10.1002/adfm.201705908
J. Song, L. Xu, J. Li, J. Xue, Y. Dong et al., Monolayer and few-layer all-inorganic perovskites as a new family of two-dimensional semiconductors for printable optoelectronic devices. Adv. Mater. 28(24), 4861–4819 (2016). https://doi.org/10.1002/adma.201600225
C. Bao, J. Yang, S. Bai, W. Xu, Z. Yan et al., High performance and stable all-inorganic metal halide perovskite-based photodetectors for optical communication applications. Adv. Mater. 30(38), e1803422 (2018). https://doi.org/10.1002/adma.201803422
B. Li, R. Long, Y. Xia, Q. Mi, All-inorganic perovskite CsSnBr 3 as a thermally stable, free-carrier semiconductor. Angew. Chem. Int. Ed. 57(40), 13154–13158 (2018). https://doi.org/10.1002/anie.201807674
M. Shoai, X. Zhang, X. Wang, H. Zhou, T. Xu et al., Directional growth of ultralong CsPbBr 3 perovskite nanowires for high-performance photodetectors. J. Am. Chem. Soc. 139(44), 15592–15595 (2017). https://doi.org/10.1021/jacs.7b08818
W. Wu, X. Han, J. Li, X. Wang, Y. Zhang et al., Ultrathin and conformable lead halide perovskite photodetector arrays for potential application in retina-like vision sensing. Adv. Mater. 33(9), e2006006 (2021). https://doi.org/10.1002/adma.202006006
M. Kulbak, S. Gupta, N. Kedem, I. Levine, T. Bendikov et al., Cesium enhances long-term stability of lead bromide perovskite-based solar cells. J. Phys. Chem. Lett. 7(1), 167–172 (2016). https://doi.org/10.1021/acs.jpclett.5b02597
Y. Lin, H. Zhang, J. Feng et al., Unclonable micro-texture with clonable micro-shape towards rapid, convenient, and low-cost fluorescent anti-counterfeiting labels. Small 17(30), e2100244 (2021). https://doi.org/10.1002/smll.202100244
J. Xue, Z. Zhu, X. Xu, Y. Gu, S. Wang et al., Narrowband perovskite photodetector-based image array for potential application in artificial vision. Nano Lett. 18(12), 7628–7634 (2018). https://doi.org/10.1021/acs.nanolett.8b03209
Z. Gu, Z. Zhou, Z. Huang, K. Wang, Z. Cai et al., Controllable growth of high-quality inorganic perovskite microplate arrays for functional optoelectronics. Adv. Mater. 32(17), e1908006 (2020). https://doi.org/10.1002/adma.201908006
W. Deng, H. Huang, H. Jin, W. Li, X. Chu et al., All-sprayed-processable, large-area, and flexible perovskite/MXene-based photodetector arrays for photocommunication. Adv. Opt. Mater. 7(6), 1801521 (2019). https://doi.org/10.1002/adom.201801521
W. Deng, J. Jie, X. Xu, Y. Xiao, B. Lu et al., A microchannel-confined crystallization strategy enables blade coating of perovskite single crystal arrays for device integration. Adv. Mater. 32(16), e1908340 (2020). https://doi.org/10.1002/adma.201908340
W. Wu, X. Wang, X. Han, Z. Yang, G. Gao et al., Flexible photodetector arrays based on patterned CH3NH3PbI3- xClx perovskite film for real-time photosensing and imaging. Adv. Mater. 31(3), e1805913 (2019). https://doi.org/10.1002/adma.201805913
L. Gu, M.M. Tavakoli, D. Zhang, Q. Zhang, A. Waleed et al., 3D arrays of 1024-pixel image sensors based on lead halide perovskite nanowires. Adv. Mater. 28(44), 9713–9721 (2016). https://doi.org/10.1002/adma.201601603
Y. Wang, C. Chen, T. Zou, L. Yan, C. Liu et al., Spin-on-patterning of Sn–Pb perovskite photodiodes on IGZO transistor arrays for fast active-matrix near-infrared imaging. Adv. Mater. Technol. 5(1), 1900752 (2019). https://doi.org/10.1002/admt.201900752
W. Lee, J. Lee, H. Yun, J. Kim, J. Park et al., High-resolution spin-on-patterning of perovskite thin films for a multiplexed image sensor array. Adv. Mater. 29(40), 1702902 (2017). https://doi.org/10.1002/adma.201702902
L. Zeng, Q. Chen, Z. Zhang, D. Wu, H. Yuan et al., Multilayered PdSe2/perovskite Schottky junction for fast, self-powered, polarization-sensitive, broadband photodetectors, and image sensor application. Adv. Sci. 6(19), 1901134 (2019). https://doi.org/10.1002/advs.201901134
A. Scholz, L. Zimmermann, U. Gengenbach, L. Koker, Z. Chen et al., Hybrid low-voltage physical unclonable function based on inkjet-printed metal-oxide transistors. Nat. Commun. 11, 5543 (2020). https://doi.org/10.1038/s41467-020-19324-5
Q. Zhu, B. Li, D. Yang, C. Liu, S. Feng et al., A flexible ultrasensitive optoelectronic sensor array for neuromorphic vision systems. Nat. Commun. 12, 1798 (2021). https://doi.org/10.1038/s41467-021-22047-w
X. Han, W. Wu, H. Chen, D. Peng, L. Qiu et al., Metal halide perovskite arrays, from construction to optoelectronic applications. Adv. Funct. Mater. 31(3), 2005230 (2020). https://doi.org/10.1002/adfm.202005230
B. Jeong, H. Han, C. Park, Micro- and nanopatterning of halide perovskites where crystal engineering for emerging photoelectronics meets integrated device array technology. Adv. Mater. 32(30), e2000597 (2020). https://doi.org/10.1002/adma.202000597
X. Zhang, Strain control for halide perovskites. Matter 2(2), 294–296 (2020). https://doi.org/10.1016/j.matt.2020.01.010
W. Feng, E. Ueda, P. Levkin, Droplet microarrays, from surface patterning to high-throughput applications. Adv. Mater. 30(20), e1706111 (2018). https://doi.org/10.1002/adma.201706111
Y. Li, B.F. Liu, X. Zhang, Wettability-patterned microchip for emerging biomedical materials and technologies. Mater. Today 51, 273–293 (2021). https://doi.org/10.1016/j.mattod.2021.10.008
L. Gu, S. Poddar, Y. Lin, Z. Long, D. Zhang et al., A biomimetic eye with a hemispherical perovskite nanowire array retina. Nature 581(7808), 278–282 (2020). https://doi.org/10.1038/s41586-020-2285-x
C.Y. Wu, Z. Wang, L. Liang, T. Gui, W. Zhong et al., Graphene-assisted growth of patterned perovskite films for sensitive light detector and optical image sensor application. Small 15(19), e1900730 (2019). https://doi.org/10.1002/smll.201900730
A. Ren, J. Zou, H. Lai, Y. Huang, L. Yuan et al., Direct laser-patterned MXene–perovskite image sensor arrays for visible-near infrared photodetection. Mater. Horiz. 7(7), 1901–1911 (2020). https://doi.org/10.1039/D0MH00537A
X. Xu, W. Liu, Z. Ji, D. Hao, W. Yan et al., Large-area periodic organic–inorganic hybrid perovskite nanopyramid arrays for high-performance photodetector and image sensor applications. ACS Mater. Lett. 3(8), 1189–1196 (2021). https://doi.org/10.1021/acsmaterialslett.1c00298
J. Jang, Y.G. Park, E. Cha, S. Ji, H. Hwang et al., 3D heterogeneous device arrays for multiplexed sensing platforms using transfer of perovskites. Adv. Mater. 33(30), e2101093 (2021). https://doi.org/10.1002/adma.202101093
B. Wang, C. Zhang, B. Zeng, C. Wu, C. Xie et al., Fabrication of addressable perovskite film arrays for high-performance photodetection and real-time image sensing application. J. Phys. Chem. Lett. 12(11), 2930–2936 (2021). https://doi.org/10.1021/acs.jpclett.1c00521
Q. Wang, G. Zhang, H. Zhang, Y. Duan, Z. Yin et al., High-resolution, flexible, and full-color perovskite image photodetector via electrohydrodynamic printing of ionic-liquid-based ink. Adv. Funct. Mater. 31(28), 2100857 (2021). https://doi.org/10.1002/adfm.202100857
K. Shen, H. Xu, X. Li, J. Guo, S. Sathasivam et al., Flexible and self-powered photodetector arrays based on all-inorganic CsPbBr 3 quantum dots. Adv. Mater. 32(22), e2000004 (2020). https://doi.org/10.1002/adma.202000004
X. Gong, M. Tong, Y. Xia, W. Xia, W. Cai et al., High-detectivity polymer photodetectors with spectral response from 300 nm to 1450 nm. Science 325(5948), 1665–1667 (2009). https://doi.org/10.1126/science.1176706
Y. Yang, R. Shi, Z. Lou, R. Chai, K. Jiang et al., Flexible smart noncontact control systems with ultrasensitive humidity sensors. Small 15(38), e1902801 (2019). https://doi.org/10.1002/smll.201902801
F. Yuan, S. Liu, J. Zhou, S. Wang, Y. Wang et al., Smart touchless triboelectric nanogenerator towards safeguard and 3D morphological awareness. Nano Energy 86, 106071 (2021). https://doi.org/10.1016/j.nanoen.2021.106071
S. Chen, Y. Wang, L. Yang, Y. Guo, M. Wang et al., Flexible and transparent sensors with hierarchically micro-nano texture for touchless sensing and controlling. Nano Energy 82, 105719 (2021). https://doi.org/10.1016/j.nanoen.2020.105719
Q. Wang, H. Ding, X. Hu, X. Liang, M. Wang et al., A dual-trigger-mode ionic hydrogel sensor for contact or contactless motion recognition. Mater. Horiz. 7(10), 2673–2682 (2020). https://doi.org/10.1039/D0MH00862A
M. Manjappa, Y. Srivastava, A. Solanki, A. Kumar, T.C. Sum et al., Hybrid lead halide perovskites for ultrasensitive photoactive switching in terahertz metamaterial devices. Adv. Mater. 29(32), 1605881 (2017). https://doi.org/10.1002/adma.201605881
H.T. Chen, W. Padilla, J. Zide, A.C. Gossard, A.J. Taylor et al., Active terahertz metamaterial devices. Nature 444(7119), 597–600 (2006). https://doi.org/10.1038/nature05343
A. Chanana, X. Liu, C. Zhang, A. Nahata, Ultrafast frequency-agile terahertz devices using methylammonium lead halide perovskites. Sci. Adv. 4(5), 7353 (2018). https://doi.org/10.1126/sciadv.aar7353
X Zhang, G Yang, and Q Liao acknowledge the support from Harvard/MIT. All others acknowledge the support by the Key Research Project of Zhejiang Laboratory (N.O. 2021PE0AC02), the National Natural Science Foundation of China (N.O. 11674210) and the Project of Hetao Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone (HZQB-KCZYB-2020083).
Open access funding provided by Shanghai Jiao Tong University.
Materials Genome Institute, Shanghai University, Shanghai, 200444, People's Republic of China
Bori Shi, Pingyang Wang, Jingyun Feng, Chang Xue & Jinbo Wu
Zhejiang Laboratory, Hangzhou, 311100, People's Republic of China
Chang Xue & Jinbo Wu
HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute, Futian, Shenzhen, People's Republic of China
Chang Xue, Weijia Wen & Jinbo Wu
School of Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
Gaojie Yang & Xingcai Zhang
School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
Qingwei Liao & Xingcai Zhang
Department of Physics, Shanghai University, Shanghai, 200444, People's Republic of China
Mengying Zhang
The Advanced Material Thrust, The Hong Kong University of Science and Technology (Guangzhou), Guangzhou, People's Republic of China
Weijia Wen
Bori Shi
Pingyang Wang
Jingyun Feng
Chang Xue
Gaojie Yang
Qingwei Liao
Xingcai Zhang
Jinbo Wu
Correspondence to Xingcai Zhang or Jinbo Wu.
Supplementary file1 (MP4 1231 KB)
Supplementary file3 (MP4 476 KB)
Supplementary file5 (DOCX 6607 KB)
Shi, B., Wang, P., Feng, J. et al. Split-Ring Structured All-Inorganic Perovskite Photodetector Arrays for Masterly Internet of Things. Nano-Micro Lett. 15, 3 (2023). https://doi.org/10.1007/s40820-022-00961-y
Split-ring
Dewetting
Perovskite photodetector array
Human–machine interface


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text:
N Leon Baer Borstein, Plaintiff–Respondent, v. Virginia Marie Henneberry, Defendant–Appellant.
Supreme Court, Appellate Division, First Department.
Decided: June 23, 2015
Gonzalez, P.J., Mazzarelli, Renwick, DeGrasse, JJ. Capuder Fazio Giacoia LLP, New York (Douglas Capuder of counsel), for appellant. Daniel A. Fried, Yonkers, for respondent.
Order, Supreme Court, New York County (Donna M. Mills, J.), entered September 27, 2013, which, to the extent appealed from as limited by the briefs, denied defendant's motion for attorneys' fees and sanctions, unanimously modified, on the law and the facts, to impose sanctions on plaintiff in the amount of $5,000, payable to the Lawyers' Fund for Client Protection, pursuant to 22 NYCRR 130–1.2 and in accordance with 22 NYCRR 130–1.3, and to award defendant reasonable costs and attorneys' fees associated with the motion and this appeal, payable by plaintiff in an amount to be determined on remand, and otherwise affirmed, with costs.
The parties were divorced pursuant to a judgment entered in December 2009. Plaintiff husband is an experienced matrimonial lawyer and he represented himself in the divorce proceeding. He was sanctioned twice during the course of that action. The first time he was ordered to pay $7,500 in attorneys' fees in connection with defendant wife's motion to enforce a pendente lite order against him. He was later directed to reimburse the wife $10,000 in connection with his violation of an order directing that a boat that was marital property be sold in an arm's length transaction, with the proceeds to be shared by the parties.
The divorce action culminated in a six-day trial. The parties submitted posttrial memoranda, and in a section entitled "Assets and Liabilities Claimed to be Marital," the husband claimed that he loaned the wife "$27,000 during the years after the filing for divorce" to allow her to finance a business venture. He also listed the loan as the sixth of nine credits totaling $1,184,500, and stated that he had "loaned to [the wife] about $27,000 after the filing for divorce and should receive a credit for the full $27,000." In addition, his Statement of Proposed Disposition, dated December 5, 2008, listed the loan in a section titled, "Assets claimed to be marital property."
The court (Gische, J.), issued a 51–page decision after trial and an order, both dated April 17, 2009, which addressed distribution of the parties' marital assets. The court noted the statutory rule that, in general, "marital property" is all property acquired by either or both spouses during the marriage but before the commencement of a matrimonial action (Domestic Relations Law § 236B[1][c] ). It rejected the husband's argument that most of the parties' assets should be classified as separate, even if acquired during marriage, because they led financially independent lives. The court reasoned that his argument was relevant to the ultimate distribution of marital assets, but not to their initial classification as marital or separate property.
In a section titled "Miscellaneous Adjustments and Credits," the court addressed certain of the credits that the husband sought, but it did not specifically address the $27,000 loan. However, in the concluding paragraph to the decision the court stated that "[a]ny arguments raised by the parties which have not been expressly addressed in this decision are rejected." The court concluded that each party was entitled to a 50% share of certain marital assets and marital debt. The judgment of divorce, which incorporated the findings, listed certain credits but did not refer to or list a credit for the loan. The husband appealed the judgment, but he did not address the loan.1
The husband then commenced this action against the wife. The complaint sought recovery of the same $27,000 sought by the husband as a credit in the divorce action. It did not refer to the divorce proceeding or the fact that the husband had sought repayment of the loan in a proceeding that had ended in a final judgment. The wife's counsel sent the husband a letter asking him to discontinue the action voluntarily because the divorce action had determined his rights regarding the loan in light of the court's ruling on the husband's request for credits.
The husband replied by letter asking, "Where is the statutory or case law that supports your position that separate property debts or assets are determined by a divorce decision[ ]? ․ If it were so obvious and 'frivolous' why have you not brought a summary judgment motion already?" The wife's counsel replied, "[T]he funds you promised and subsequently transferred to your then wife were marital property."
The wife did eventually move for summary judgment dismissing the complaint, arguing that the husband's claim was barred by res judicata principles because it had been fully litigated in the divorce action. She also argued that the loan was not enforceable because the funds that the husband transferred to her were marital property. The wife submitted excerpts from the husband's deposition testimony in the matrimonial action, in which he acknowledged that the loan funds were derived from compensation he received for an arbitration or mediation he completed while the parties were married. He also admitted that he had sought a credit for the loan in the divorce action.
Supreme Court (Mills, J.), granted the wife's motion and dismissed the complaint, concluding that the loan was "fully and actively litigated by [the husband]" in the divorce action. It rejected the husband's argument that the issue was never fully litigated because there was no formal finding that the source of the loan was marital property. The court noted that the husband sought specific relief for the loan in the divorce action in the form of a credit, which was denied, and that the husband sought to relitigate that same issue in the instant action. The court also noted that in the decision after trial, the court in the divorce action stated that it rejected any argument raised by the parties that it had not expressly addressed. The court also rejected the husband's argument that he still had an independent cause of action because "the 'loan' w[as] never identified as a 'marital' asset and/or there was no specific discussion of offset of the 'loan' when marital assets were distributed." It cited his concessions in his filings in the divorce action that the source of funds for the loan was marital property.
The wife subsequently moved, pursuant to 22 NYCRR part 130 and Rules of Professional Conduct (22 NYCRR 1200.0) rule 3.1(a) and (b), for an order awarding her attorneys' fees, costs, disbursements, and sanctions due to the husband's "frivolous and improperly motivated" lawsuit. She argued that the husband's pursuit of the action required the wife's counsel to conduct discovery, depose the husband, defend the wife's deposition, make related discovery motions, and spend time trying, unsuccessfully, to persuade the husband to discontinue the action without the expense of a summary judgment motion. The court held that the husband's conduct in seeking repayment of the loan was not so frivolous as to warrant sanctions pursuant to 22 NYCRR part 130; however, as the court had dismissed the action in its entirety, it awarded the wife costs and disbursements in successfully defending the action.
A court may, in its discretion, award to any party costs in the form of reimbursement for expenses reasonably incurred and reasonable attorneys' fees resulting from "frivolous conduct," which includes: (1) conduct completely without merit in law, which cannot be supported by a reasonable argument for an extension, modification or reversal of existing law; (2) conduct undertaken primarily to delay or prolong the resolution of the litigation, or to harass or maliciously injure another; and (3) the assertion of material factual statements that are false (22 NYCRR 130–1.1[a], [c][3] ). The court may also award financial sanctions on the same grounds (22 NYCRR 130–1.1[b] ).
In determining whether conduct is frivolous, the court shall consider "the circumstances under which the conduct took place, including the time available for investigating the legal or factual basis of the conduct, and whether or not the conduct was continued when its lack of legal or factual basis was apparent, should have been apparent, or was brought to the attention of counsel" (22 NYCRR 130–1.1[c] ).
Here, the husband made a claim in the divorce action for repayment of the $27,000 "loan," and Supreme Court rejected it. He then failed to challenge that finding on direct appeal. Any argument that Supreme Court did not actually decide the issue of the "loan" because it did not specifically address it is rejected, since the court included the "catch-all" language that any claims not discussed were denied. In any event, the husband could have sought clarification from the court if he felt that the claim related to the "loan" had escaped the court's attention. Indeed, it would have behooved him to do so, as it is well settled that "res judicata bars a subsequent plenary action concerning an issue of marital property which could have been, but was not, raised in the prior matrimonial action" (Boronow v. Boronow, 71 N.Y.2d 284, 289 [1988] ). Again, we are required to consider "the circumstances under which the conduct took place" when reviewing a sanctions motion (22 NYCRR 130–1.1[c] ). Here, the circumstances are that the husband, an experienced divorce lawyer, ignored a long-standing principle of matrimonial jurisprudence. Thus, his decision to commence an action that he knew, or should have known, was futile from its inception, weighs heavily in favor of a finding that his conduct was intended solely to harass the wife.
We are mindful of the notion that a court must be careful not to confuse legal arguments that may appear at first blush to be frivolous with good faith efforts to modify existing law (see W.J. Nolan & Co. v. Daly, 170 A.D.2d 320, 321 [1st Dept 1991] ). There is no cause for such concern here. The husband argues that an enforceable loan can be made from marital property, and that this Court has "strongly impl[ied]" this to be the case. However, the case he cites, Popowich v. Korman (73 AD3d 515 [1st Dept 2010] ), merely suggests that one spouse may enforce a loan to the other if the loan is pursuant to a written agreement signed by the parties and acknowledged, in accordance with Domestic Relations Law § 236(B)(3). Here, there is no question that no such agreement existed. Accordingly, the matrimonial court was unquestionably correct in hewing to the rule that property accumulated by the parties during the marriage but before commencement of a divorce action is marital property subject to equitable distribution.
In any event, the issue is not whether the husband should have prevailed on his claim in the matrimonial action, but whether he had any grounds for pursuing the matter after that action became final. It simply defies logic that, as the husband argues, the court in the matrimonial action would have implicitly ruled that the loan was separate property, when he conceded before it that the source of the funds was marital property. Further, the husband utterly fails to account for the court's explicit statement that any arguments it did not address should be considered rejected.
Aside from the blatant lack of merit to the complaint, other factors justifying sanctions and attorneys' fees are present here. First, the wife expressly informed the husband that she considered the action barred by res judicata and urged him to discontinue it, but he pressed on, forcing her to expend unnecessary resources. Such unreasonable persistence in a position that has been demonstrated to be frivolous warrants the imposition of sanctions (see Cattani v. Marfuggi, 74 AD3d 553 [1st Dept 2010] [plaintiff insisted on pursuing action against defendant that he had been advised was cloaked with absolute immunity from suit] ). Further, we cannot ignore that this is not the first instance in which the husband has taken a position that is not legally tenable. He was ordered in the matrimonial action to pay the wife's legal fees in connection with his noncompliance with a temporary support order. While the court did not expressly opine that his conduct was frivolous, it can be presumed that he failed to present any good faith basis for his failure to abide by the order. Later in the action, however, the court explicitly stated that the husband had "frivolously" asked it to "re-write its decision" regarding the forced sale of a boat so as to make his actions, which failed to comply with the decision, compliant nunc pro tunc. Coupled with these earlier incidents, the commencement of this action exhibits a "broad pattern ․ of delay, harassment and obfuscation" that warrants the imposition of sanctions and attorneys' fees (Levy v. Carol Mgt. Corp., 260 A.D.2d 27, 33 [1st Dept 1999] ).
FN1. 1 On appeal, this Court modified the divorce judgment only to the extent that it reclassified as marital property certain debt adjudged by Supreme Court to be the wife's separate property, and increased the wife's share of appreciation on a farm owned by the parties (Henneberry v. Borstein, 87 AD3d 451 [1st Dept 2011] ).. FN1. 1 On appeal, this Court modified the divorce judgment only to the extent that it reclassified as marital property certain debt adjudged by Supreme Court to be the wife's separate property, and increased the wife's share of appreciation on a farm owned by the parties (Henneberry v. Borstein, 87 AD3d 451 [1st Dept 2011] ).