Resolving the Energy of γ-Ray Photons with MAPbI₃ Single Crystals

Halide perovskites exhibit remarkably high-performance as semiconductors compared to conventional materials because of an unusually favorable combination of optoelectronic properties. We demonstrate here that solution-grown single-crystals of organic-inorganic hybrid perovskite CH₃NH₃PbI₃ (MAPbI₃), implemented in a Schottky-type device design, can produce outstanding hard radiation detectors with high spectral response and low dark current for the first time. Schottky-type MAPbI₃ detector achieves an excellent energy resolution of 6.8% for ⁵⁷Co 122 keV gamma ray. The high detector performance is achieved due to the balanced charge collection efficiency for both electrons and holes, reflected in the high mobility-lifetime (μτ) products of both carriers (∼0.8 × 10^-3 cm²/V). MAPbI₃ also demonstrates remarkably long electron and hole lifetimes (τ_e = 10 μs and τ_h = 17 μs) and impressive operational stability over time. Furthermore, dual-source detection of α particle (5.5 MeV) and γ-ray (59.5 keV) from the ²⁴¹Am radiation source is achieved simultaneously by Schottky-type MAPbI₃ detector. These results reveal the great potential of MAPbI₃ as a high-performance, low-cost radiation detection material.