Kilogram‐Scale Crystallogenesis of Halide Perovskites for Gamma‐Rays Dose Rate Measurements
Pavao Andričević, Pavel Frajtag, Vincent Lamirand, Andreas Pautz, Márton Kollár, Bálint Náfrádi, Andrzej Sienkiewicz, Tonko Garma, L. Forró, Endre Horváth
Abstract
Abstract Gamma‐rays ( γ ‐rays), wherever present, e.g., in medicine, nuclear environment, or homeland security, due to their strong impact on biological matter, should be closely monitored. There is a need for simple, sensitive γ ‐ray detectors at affordable prices. Here, it is shown that γ ‐ray detectors based on crystals of methylammonium lead tribromide (MAPbBr 3 ) ideally meet these requirements. Specifically, the γ ‐rays incident on a MAPbBr 3 crystal generates photocarriers with a high mobility‐lifetime product, allowing radiation detection by photocurrent measurements at room temperatures. Moreover, the MAPbBr 3 crystal‐based detectors, equipped with improved carbon electrodes, can operate at low bias (≈1.0 V), hence being suitable for applications in energy‐sparse environments, including space. The γ ‐ray detectors reported herein are exposed to radiation from a 60 Co source at dose rates up to 2.3 Gy h −1 under ambient conditions for over 100 h, without any sign of degradation. The excellent radiation tolerance stems from the intrinsic structural plasticity of the organic–inorganic halide perovskites, which can be attributed to a defect‐healing process by fast ion migration at the nanoscale level. The sensitivity of the γ ‐ray detection upon volume is tested for MAPbBr 3 crystals reaching up to 1000 cm 3 (3.3 kg in weight) grown by a unique crystal growth technique.