Growth of MAPbI3 single crystals for radiation detection and sensor applications

This work investigates the growth, structural characteristics, and proof-of-concept radiation response of methylammonium lead iodide (MAPbI3) single crystals for direct x-ray and γ-ray detection. Large, optically clear MAPbI3 single crystals were synthesized using a modified cyclic inverse temperature crystallization (ITC) approach, enabling repeated growth within a single precursor solution under controlled thermal conditions. The resulting crystals exhibited well-defined faceted morphologies with dimensions ranging from millimeters to centimeters and high structural quality. Schottky barrier photodetectors fabricated using these crystals exhibited high photosensitivity (3.68 × 105 μC Gy−1 cm−2), a low detection limit (0.0114 μGy s−1), and excellent linearity under x-ray and γ-ray irradiation. The results demonstrate that cyclic ITC provides a reproducible and material-efficient pathway for producing high-quality MAPbI3 single crystals suitable for direct ionizing radiation detection.