标题：Highly Efficient and Stable Self-Powered Ultraviolet and Deep-Blue Photodetector Based on Cs2AgBiBr6/SnO2 Heterojunction
作者：Wu, Cuncun; Du, Bowen; Luo, Wei; Liu, Yang; Li, Tieyi; Wang, Duo; Guo, Xuan; Ting, Hungkit; Fang, Zheyu; Wang, Shufeng; Chen, Zhij 更多 作者机构：[Wu, Cuncun; Du, Bowen; Luo, Wei; Liu, Yang; Li, Tieyi; Wang, Duo; Guo, Xuan; Ting, Hungkit; Fang, Zheyu; Wang, Shufeng; Chen, Zhijian; Xiao, Lixin] P 更多
通讯作者：Wang, SF;Xiao, LX;Wang, SF;Xiao, LX;Chen, YX;Chen, YX;Xiao, LX
通讯作者地址：[Wang, SF; Xiao, LX]Peking Univ, State Key Lab Mesoscop Phys, Beijing 100871, Peoples R China;[Wang, SF; Xiao, LX]Peking Univ, Dept Phys, Beijing 1008 更多
来源：ADVANCED OPTICAL MATERIALS
关键词：Cs2AgBiBr6/SnO2 heterojunction; double perovskite Cs2AgBiBr6;; responsivity; ultraviolet photodetectors
摘要：Ultraviolet (UV) photodetectors with high responsivity and fast response are crucial for practical applications. Double perovskite Cs2AgBiBr6 has emerged as a promising optoelectronic material due to its excellent physics and photoelectric properties. However, no work is reported based on its film for photodetector applications. Herein, an ITO/SnO2/Cs2AgBiBr6/Au hole-transport layer free planar heterojunction device is fabricated for photodetector application. The device is self-powered with two responsivity peaks at 350 and 435 nm, which is suitable for ultraviolet-A (320-400 nm) and deep-blue light detecting. A high responsivity of 0.11 A W-1 at 350 nm and a quick response time of less than 3 ms are obtained, which is significantly higher than other semiconductor oxide heterojunction-based UV detectors. More importantly, the stability is significantly better than most of the hybrid perovskite photodetectors reported so far. Its photocurrent shows no obvious degradation after more than 6 months storage in ambient conditions without any encapsulation. Consequently, the utilization of Cs2AgBiBr6 film is a practical approach for high performance, large-area lead-free perovskite photodetector applications. For the mechanism, it is found that photogenerated carriers in Cs2AgBiBr6 film are separated at the Cs2AgBiBr6/SnO2 heterojunction interface by its built-in field. The low toxicity and high stability of this double perovskite active layer make it very promising for practical applications.