Free-Space Anisotropy-Modulated Growth of Large-Area, High-Aspect-Ratio Perovskite Single Crystals for High-Performance Radiation Detectors

Perovskite single crystals have demonstrated tremendous application potential in radiation detection. Large-area, high-aspect-ratio perovskite single crystals are desired for array-based detection and imaging. However, the growth of high-aspect-ratio perovskite single crystals currently relies predominantly on the space-confined method, which suffers from prolonged processing times and, more critically, a restriction on the lateral size of the resulting crystals imposed by the solute transport efficiency within the confined space. Here, we report a strategy for fabricating high-aspect-ratio single crystals in unconfined, free space. We demonstrate that the anisotropic regulation of solution temperature and seed crystal size enables the realization of anisotropic crystal growth in free space, without impeding the kinetics of solute transport. Finally, a large-area, high-aspect-ratio perovskite single crystal with dimensions of 40 × 33 × 3.8 mm3 has been grown, which exhibits a high X-ray detection sensitivity of 1.73 × 104 μC Gy–1 cm–2 and the lowest detectable dose rate of 34.1 nGy s–1. The on/off ratio per dose rate reaches 9.365 × 104 s Gy–1, which is the highest among MAPbBr3 single-crystal devices reported to date. This work provides a new strategy for the growth of large-sized, high-aspect-ratio perovskite single crystals.