Rubidium Doping to Enhance Carrier Transport in CsPbBr3 Single Crystals for High-Performance X-Ray Detection

Junchi Li; Xinyuan Du; Guangda Niu; Haipeng Xie; Yifu Chen; Yongbo Yuan; Yongli Gao; Hanning Xiao; Jiang Tang; Anlian Pan; Bin Yang

doi:10.1021/acsami.9b14772

Rubidium Doping to Enhance Carrier Transport in CsPbBr₃ Single Crystals for High-Performance X-Ray Detection

ACS Appl Mater Interfaces. 2020 Jan 8;12(1):989-996. doi: 10.1021/acsami.9b14772. Epub 2019 Dec 20.

Authors

Junchi Li, Xinyuan Du¹, Guangda Niu¹, Haipeng Xie², Yifu Chen², Yongbo Yuan², Yongli Gao³, Hanning Xiao, Jiang Tang¹, Anlian Pan, Bin Yang

Affiliations

¹ Wuhan National Laboratory for Optoelectronics (WNLO), School of Optical and Electronic Information , Huazhong University of Science and Technology (HUST) , Wuhan 430074 , China.
² Hunan Key Laboratory of Super Microstructure and Ultrafast Process, School of Physics and Electronics , Central South University , Changsha , Hunan 410083 , China.
³ Department of Physics and Astronomy , University of Rochester , Rochester , New York 14627 , United States.

PMID: 31818105
DOI: 10.1021/acsami.9b14772

Abstract

The direct band gap CsPbBr₃ perovskite is regarded as a promising alternative for low-cost and high-performance X-ray radiation detectors. Despite the fact that CsPbBr₃ nanocrystals have been shown to be good scintillators in the indirect conversion mode, the direct X-ray conversion with CsPbBr₃ single crystals is expected to yield higher spatial resolution. Here, rubidium (Rb) doping is demonstrated to be an efficient approach to improve carrier transport and X-ray detection performance in the direct-conversion X-ray detectors based on Cs_(1-x)Rb_xPbBr₃ single crystals. Electrical properties' characterizations as combined with X-ray photoelectron spectroscopy (XPS) measurements have revealed that Rb doping in Cs_(1-x)Rb_xPbBr₃ single crystals can enhance the atomic interaction and orbital coupling between Pb and Br atoms, leading to an enhancement of carrier transport and X-ray detection performance. X-ray detectors based on a small amount (0.037%) of Rb-doped Cs_(1-x)Rb_xPbBr₃ single crystals exhibited a high X-ray sensitivity of 8097 μC Gy_air^-1 cm^-2. This work offers a feasible strategy to improve the X-ray detection performance by chemical doping in all-inorganic perovskite X-ray detectors.

Keywords: X-ray detector; all-inorganic perovskite; carrier transport; cesium lead bromide; rubidium doping.