Stable Hard X-ray Detectors by High-Charge-Mobility Two-Dimensional Cu(Gly)<sub>2</sub>Pb<sub>2</sub>Br<sub>4</sub> Single Crystal
J.H. Han, Weijun Li, Jinmei Song, Mingbian Li, Yuhong He, Wei Wei, Bai Yang, Haotong Wei
Abstract
Two-dimensional (2D) perovskites have better long-term stability, better ion migration inhibition ability, and lower dark current in X-ray detection due to the hindrance effect of organic cations. However, this also limits the charge carrier transport and lowers the device sensitivity. Here, we report a new trans-copper glycinate lead bromide (Cu(Gly) 2 Pb 2 Br 4 ) perovskite-like single crystal. Through the cross-linking strategy of metal ions, the charge carrier transport ability of Cu(Gly) 2 Pb 2 Br 4 along the out-of-plane direction was greatly improved. The record high hole mobility of 54.1 cm 2 V –1 s –1 enables a high sensitivity of 26 589 μC Gy air –1 cm –2 . The cross-linking structure of the organic interlayer also inhibits ion migration paths and enhances stability with a small dark current drift as low as 4.93 × 10 –18 A cm –1 V –1 s –1 . The Cu(Gly) 2 Pb 2 Br 4 single crystal also shows good stability and X-ray imaging capability as a potential candidate for X-ray detection.