Visible blind detector

Adv. Mater. http://dx.doi.org/10.1002/adma.201301828 (2013)

The development of transparent optoelectronics and electronics is potentially useful for applications involving displays, solar cells, sensors and batteries. Now, Wei Tian and co-workers, who are based in Japan and China, report an ultraviolet detector that is intrinsically 'visible blind', being highly transparent (approximately 90% transmission) in the visible region. The researchers claim that the device is simple and inexpensive to fabricate as it is based on ZnO–SnO₂ heterojunction nanofibres produced by electrospinning. Its photoresponse increases significantly when it is illuminated with ultraviolet light with a wavelength of ∼350 nm or shorter, whose photon energy exceeds the bandgap of the ZnO–SnO₂ nanofibres. The researchers note that the photodetector exhibits excellent operating characteristics, including a high sensitivity, a high photo/dark current ratio and a fast response speed. The synthesis and fabrication procedure is expected to be easily extendable to other heterostructures such as TiO₂–SnO₂ and ZnO–TiO₂, which also have the potential to be used to produce transparent ultraviolet detectors.