Surface conversion of ZnO nanorods to ZIF-8 to suppress surface defects for a visible-blind UV photodetector

摘要: ZnO nanomaterials are promising building blocks for an efficient UV photodetector; however, their slow sensing behavior and undesired response to visible light, which attributed surface defects, such as oxygen or zinc vacancies, challenges that remain be addressed. Here, we transformed the nanorod into a zeolitic imidazolate framework-8 (ZIF-8) eliminate defects. Vertical-type photodetectors were fabricated incorporating Schottky junction at ZIF-8/gold (Au) top electrode could respond light with rapid recovery (1-2 s) demonstrated UV-to-visible rejection ratio in order of 103, qualifying them visible-blind photodetectors. It is noteworthy ZIF-8 layer effectively separated photogenerated electron-hole pairs, thus reduced recombination probability. The enhanced photodetector displayed excellent figures-of-merit: responsivity 291 A W-1 detectivity 5.9 × 1013 cm Hz1/2 under illumination 295 nm.