Enhanced Carrier Transport in X‐Ray Detector Based on Cs<sub>3</sub>Bi<sub>2</sub>I<sub>9</sub>/MXene Composite Wafers
Shunyong Wei, Shujie Tie, Kai Shen, Hui Sun, Xiaojia Zheng, Hao Wang, Wenqing Liang, Jihua Zou, Yixuan Huang, Lingzhi Luo, Xiangyu Zhou, Tixian Zeng, Aobo Ren, Dewei Zhao, Jiang Wu
Abstract
Abstract Intrinsically high attenuation of X‐rays and excellent optoelectronic properties endow Cs 3 Bi 2 I 9 with great promise for high‐performance X‐ray detectors. However, preparation of high quality Cs 3 Bi 2 I 9 single crystal with large area and millimeter‐thick remains challenging and time‐consuming. A size scalable growth technology, a mechanical sintering process, which is applicable for the integration in image detectors is proposed in this work. Compared with the Cs 3 Bi 2 I 9 wafer, the Cs 3 Bi 2 I 9 /MXene composite wafer exhibits higher carrier transfer efficiency and mobility‐lifetime product through incorporation of Ti 3 C 2 T x MXene multilayer nanoflakes (MXene nanoflakes). The Cs 3 Bi 2 I 9 /MXene composite wafer X‐ray detector shows an excellent linearity of X‐ray response, a fast response speed, and a low limit of detection of 231 nGy air s −1 . The sensitivity of 368 µC Gy air −1 cm −2 under 120 V mm −1 is achieved, which is 15.4% enhanced over the Cs 3 Bi 2 I 9 wafer detector. The sensitivity of Cs 3 Bi 2 I 9 /MXene wafer device enhances ≈20–40% at low applied voltage regime. In addition, the Cs 3 Bi 2 I 9 /MXene wafer detector exhibits excellent operational stability after storage for 12 months in ambient air. This work provides an alternative approach for realization of next‐generation high‐performance perovskite X‐ray detectors.