|
|||||
|
|
Suppression of Ionic and Electronic Conductivity by Multilayer Heterojunctions Passivation Toward Sensitive and Stable Perovskite X-Ray Detectors |
|
| Authors: | Mingyue Han Yingrui Xiao Chao Zhou Zijie Xiao Wenyan Tan Guowei Yao Xiaoxue Wu Renzhong Zhuang Shiming Deng Qi Hu Yuxuan Yang Zhaoheng Tang Xunsheng Zhou Haobo Lin Huili Liang Shenghuang Lin Zengxia Mei Cailin Wang Qi Chen Wei Zhang Yan Jiang |
| Affiliation: | 1. School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081 China School of Physics and Materials Science, Guangzhou University, Guangzhou, Guangdong, 510006 China;2. Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523429 China;3. School of Physics and Materials Science, Guangzhou University, Guangzhou, Guangdong, 510006 China;4. Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523429 China MOE Key Laboratory of Laser Life Science & Guangdong Provincial Key Laboratory of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631 China;5. School of Physics and Materials Science, Guangzhou University, Guangzhou, Guangdong, 510006 China Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523429 China;6. Longyan University, Longyan, Fujian, 364012 China;7. HAMAMATSU Photonics (China) Co., LTD. 8. , Beijing, 100020 P. R. China;9. School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081 China |
| Abstract: | Organic-inorganic hybrid perovskites are promising candidates for direct X-ray detection and imaging. The relatively high dark current in perovskite single crystals (SCs) is a major limiting factor hindering the pursuit of performance and stability enhancement. In this study, the contribution of dark current is disentangled from electronic (σe) and ionic conductivity (σi) and shows that the high σi dominates the dark current of MAPbBr3 SCs. A multilayer heterojunctions passivation strategy is developed that suppresses not only the σi by two orders of magnitude but also σe by a factor of 1.6. The multilayer heterojunctions passivate the halide vacancy defects and increase the electron and hole injection barrier by inducing surface p-type doping of MAPbBr3. This enables the MAPbBr3 SC X-ray detectors to obtain a high sensitivity of 19 370 µC Gyair−1 cm−2 under a high electric field of 100 V cm−1, a record high sensitivity for bromine self-powered devices, and a low detection limit of 42.3 nGyair s−1. The unencapsulated detectors demonstrate a stable baseline after storage for 210 days and outstanding operational stability upon irradiation with an accumulated dose of up to 1944 mGyair. |
| Keywords: | dark current electronic and ionic conductivity multilayer heterojunctions perovskite X-ray detectors stability |