Ultraviolet Optoelectronic Devices Based On ZnO Nanocrystals

ZnO has a potential application prospect in the ultraviolet detector and ultraviolet light-emitting device for its strong radiation tolerance, high exciton binding energy, low growth temperature, and matching single crystal substate. In this paper, we prepared the ZnO nanocrystals by the sol-gel method, and then constructed ultraviolet detector and ultraviolet light-emitting devices. The main results are listed below:Fristly by utilizing Schottky contact in device, contacting fast response ultraviolet photodetectors based on solution-processed ZnO nanocrystals. At 5 V, the detector exhibits fast photoresponse with a rise time of 20 ns and fall time of 350 ns, which is one of the fastest response time among the reported Zn O-based photodetectors. The results reported in this paper may show great promise for fast response optoelectronic devices based on solution-processed nanocrystals.Finally constructing the Au/ZnO/Au structured ultraviolet light-emitting devices based on solution-processed ZnO nanocrystals.The electroluminescence spectrum of the device is composed of two peaks. The strong one located at 384 nm corresponds to the near band edge emission of ZnO, while the weak one located at 566 nm is related to ZnO defects. With the increase of pump current, the enhancement of ultraviolet emission is more obvious than that of visible emission.