Cupric oxide (CuO) is an intrinsic p-type semiconductor that has a high capacitance and a strong ability to absorb sunlight.
The degree of crystallinity of CuO is important for its functional role in a particular electronic device. For example, highly crystalline CuO is suitable for photovoltaic devices, e.g., solar cells. Typically, CdTe semiconductors are used in thin film photovoltaic devices in the US. Cd is toxic and Te is rare. By contrast, CuO is safe and abundant, making it an ideal replacement for CdTe.
Of note, CuO, having a low degree of crystallinity, performs better than highly crystalline CuO in energy storage devices such as batteries and supercapacitors. In both photovoltaic devices and energy storage devices, morphologies of the semiconductor also play an important role in determining their electrical and optical properties. See, Osherov et al., J. Chem. Mater. 2013, 25, 692-98 and Wang et al., Appl. Mater. Interfaces 2014, 6, 1243-50. However, conventional CuO semiconductors do not possess optimized degrees of crystallinity and controllable morphologies. Indeed, no existing methods can be used to prepare CuO semiconductors having both a predetermined degree of crystallinity and a desired morphology.
There is a need to develop CuO semiconductors with predetermined degrees of crystallinity and favorable morphologies for use in electronic devices.