CH₃NH₃PbBr₃ Perovskite Single-Crystal X-Ray Photon-Counting Detection Based on Multi-Layer Electrodes

CH₃NH₃PbBr₃ (MAPbBr₃) single crystals have shown great potential in X/γ-ray detection. However, stable electrodes for MAPbBr₃ single crystals still remain challenging. In this work, multi-layer electrodes including Au, Au/Ti and Au/Pt/Ti are investigated. Through I-V characterization, Au/Pt/Ti shows Ohmic contact behavior and the lowest dark current. The potential contact is also confirmed by the Kelvin force probe. Based on these low-noise electrodes, 59.5 keV monochromatic X-ray photon-counting detection and imaging is demonstrated. This work provides useful information for electrode design in lead halide perovskite-based optoelectronic devices.