Meet the Researcher: A Chemist Triggered by Light
Advanced applications of 3D laser lithography can open avenues for new material design. Bioengineers will be able to make new, better implants like artificial retinas. Materials scientists can create meta materials with highly specific property features. And 3D printing at the nanoscale has exciting potential applications in integrated circuit manufacture.

However, innovations in the photochemistry underpinning 3D laser lithography are critical to realising these futuristic aims. Dr Sandra Wiedbrauk is at the forefront of this photochemical innovation push.

Wiedbrauk built extensive experience in photochemistry at the Ludwig-Maximilians-University Munich, and she is currently fusing that knowledge with new advancements in polymer chemistry at QUT. (Read the papers: “Simultaneous complementary photoswitching of hemithioindigo tweezers for dynamic guest relocalization” and “Visible‐Light‐Induced Passerini Multicomponent Polymerization”.)

In this new research, light acts as a ‘switch’ for molecular reactivity to modulate the molecules’ ability to react with functional reactants– findings that she recently published in the industry-leading Chemistry: A European Journal.

“Using this ‘switching’ technology, we can use light to manipulate how polymers are fused together during 3D printing,” Wiedbrauk said.

“At the moment, I am working with molecules that have a linear non-reactive structure, which are able change into a reactive structure by photostimulation.”

Although Wiedbrauk’s research is in the early stages of being applied to 3D-printed materials, the real-world applications could have far-reaching impacts.

The potential for 3D printed cells and organelles

It sounds like science fiction, yet the photochemistry explored by Wiedbrauk could critically contribute to the design of photoresists that will ultimately be used in the micro and nanoprinting applications, such as 3D printed cells.

A single 3D printer could be used to fabricate different cell components by using multiple colours of light and materials, which are developed in QUT’s Soft Matter Materials Laboratory.

“With advanced 3D laser lithography, sub-micron structures can be printed, ultimately allowing to print complex bioactive structures” Wiedbrauk explained.

Smaller, smarter electronics

Technology based on advanced photochemistry could also be used to 3D print electronic circuits at the nanoscale, opening the door to highly simplified integrated circuitry manufacture from a 3D printer.

“This could mean that electronic items such as smartphones and tablets can be manufactured at a fraction of today’s price” Wiedbrauk said.

“And it’s not just the cost, but also the size of electronics that can change with more streamlined manufacturing processes.

“Imagine a pacemaker at a fraction of the size of current devices — its smaller size means it would be safer and easier to implant within the body.”

The future of solar power

Looking further afield than her current research project focused on developing advanced photochemistry with potential applications in 3D laser lithography, Wiedbrauk has plans to exploit photochemical reactions for solar power generation.

“When we shine light on specific molecules, they can change geometry — like from a straight line into a sphere, for example,” Wiedbrauk explained.

“When the light is switched off — or when the sun sets — the molecule relaxes back into its original shape, releasing a small amount of heat.

“The process could be scaled up so that you had billions of molecules transformed with sunlight during the day, then relaxing and releasing heat at night. And that heat could be captured and converted to energy.”

The technology is perhaps an innovative promising avenue for solar energy storage, and Wiedbrauk plans to take a proof of concept to the testing phase in her future research endeavours.

“I am an expert in photochemistry and materials science, and I want to combine these fields to address the pressing problem of reliable energy storage from the most abundant power source we know: the sun,” Wiedbrauk said.

“QUT’s Soft Materials Laboratory and Centre for Materials Science provide an ideal interdisciplinary platform for my research.”

Wiedbrauk is currently exploring the frontiers of photochemistry in the context of a post-doctoral fellowship within the Australian Research Council’s (ARC) Laureate Fellowship program of Professor Christopher Barner-Kowollik.

More information

Contact Dr Sandra Wiedbrauk

Explore QUT’s Soft Matter Materials Laboratory and QUT’s Centre for Materials Science

Explore research at QUT
['The Labs']
['Science', 'Chemistry', 'Innovation', 'Materials Science']