All-inorganic CsAgBiBr/Cu SCN-based photodetectors for weak light imaging

作     者：Genghua Yan Zhong Ji Zhuowei Li Bangqi Jiang Min Kuang Xiang Cai Ye Yuan Wenjie Mai 颜庚骅;计钟;李卓伟;江邦齐;况敏;蔡祥;袁野;麦文杰

作者机构：Siyuan LaboratoryGuangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy MaterialsDepartment of PhysicsJinan UniversityGuangzhou510632China Guangdong Provincial Key Laboratory of Optical Fiber Sensing and CommunicationsJinan UniversityGuangzhou510632China Guangdong Institute of New MaterialsGuangdong Academy of SciencesGuangzhou510650China Department of Light Chemical EngineeringGuangdong PolytechnicFoshan528041China 

出 版 物：《Science China Materials》 (中国科学（材料科学（英文版）)

年 卷 期：2021年第64卷第1期

页      面：198-208页

核心收录：

学科分类：08[工学] 0803[工学-光学工程] 

基　　金：supported by the National Natural Science Foundation of China (51772135) the Ministry of Education of China (6141A02022516) the Fundamental Research Funds for the Central Universities (11619103) China Postdoctoral Science Foundation (2019M663376) Guangdong Province Higher Vocational Colleges & Schools Pearl River Scholar Funded Scheme (2017) the Natural Science Foundation of Guangdong Province, China (2017A020215135 and 2018A030310659) the Science and Technology Program of Guangzhou, China (201804010432) 

主　　题：photodetector weak light imaging all-inorganic perovskite Cs2AgBiBr6 double perovskite CuSCN inorganic hole-transport layer 

摘      要：Weak light imaging has drawn more and more attention because of its promising potential for practical applications in security monitoring and space exploration. In this work, all-inorganic Cs2AgBiBr6 double perovskite-based self-powered photodetectors containing inorganic copper thiocyanate(CuSCN) as hole-transport layers(HTLs) are successfully fabricated and applied for weak light imaging,which is the first report on the weak light imaging application of all-inorganic lead-free perovskite photodetectors. CuSCN films with favorable optical property and hole extraction capability are prepared via a cost efficient and fast solvent removal method, demonstrating the potential for high-performance perovskite-based devices as transparent components. It is revealed that the band alignment of the device is effectively optimized with the presence of CuSCN HTLs,which can availably transport holes while block electrons at the Cs2AgBiBr6/CuSCN interface, resulting in remarkable improvement of photoresponse performance. The responsivity and detectivity are 0.34 A W^-1 and 1.03×10^13 Jones,respectively. In particular, the light current has a boost of almost 10 times. Furthermore, the photodetectors are integrated into a self-built light detection imaging system utilizing the focused laser scanning imaging mode. With illumination of as low as 5 nW cm^-2(405 nm), the image involving graphics and words with a size of 5 cm×5 cm can still be distinctly recognized. These results suggest the promising potential of all-inorganic perovskite-based devices for weak light detection and imaging applications.