Kilogram-Scale Crystallogenesis of Halide Perovskites for Gamma-Rays Dose Rate Measurements.

Pavao Andričević,Pavel Frajtag,László Forró,Andreas Pautz,Vincent Pierre Lamirand,Márton Kollár,Bálint Náfrádi,Tonko Garma,Andrzej Sienkiewicz,Endre Horváth

doi:10.1002/advs.202001882

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 (MAPbBr3) ideally meet these requirements. Specifically, the γ‐rays incident on a MAPbBr3 crystal generates photocarriers with a high mobility‐lifetime product, allowing radiation detection by photocurrent measurements at room temperatures. Moreover, the MAPbBr3 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 60Co 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 MAPbBr3 crystals reaching up to 1000 cm3 (3.3 kg in weight) grown by a unique crystal growth technique.

Highlights

Radiation detectors are extensively used in various domains, including environment, or homeland security, due to their strong impact on biological industry, nuclear power plants, homeland matter, should be closely monitored
The γ-ray detectors reported are exposed to radiation from a 60Co source at dose must have multiple distinct characteristics, such as large detection volume to intercept radiation, an elevated linear attenuation coefficient, large and balanced carrier mobilities (μ) concomitant with long charge carrier lifetimes (τ), leading to high valrates up to 2.3 Gy h−1 under ambient conditions for over 100 h, without any ues of their product, which is a prereqsign of degradation
We introduce the “oriented crystal-crystal intergrowth” method, hereinafter referred to as oriented crystalcrystal intergrowth (OC2G) technique, which yielded solutiongrown MAPbBr3 crystals with volume and mass of over 1000 cm3 and 3 kg, respectively

Summary

Introduction

Radiation detectors are extensively used in various domains, including environment, or homeland security, due to their strong impact on biological industry, nuclear power plants, homeland matter, should be closely monitored. Detectors designed around larger MAPbBr3 SCs, having the same spacing between the silver electrodes, were exposed to the γ-source, as schematically shown in Figure S5c in the Supporting Information.

Results

Conclusion