Controllable Growth of High Quality MAPbX₃ Perovskite Single Crystals for X-ray Detection

The crystal quality limits the mobility-lifetime (μτ) product and the further applications of perovskite single crystals (PSC) in high energy radiation detections regardless of their high attenuation coefficient. In this paper, high-quality and controllable growth of MAPbX3 PSCs is demonstrated using the liquid-diffusion induced crystallization (LDSC) method. The growth kinetics are modeled to demonstrate the feasibility of the controllable growth via keeping the growth in the mass-transport-limited regime. The crystal growth rate is confirmed theoretically and experimentally to be constant and solely dependent on the growth temperature. A facile method is developed to measure the growth rate without disturbing or suspending the whole process. MAPbBr3 PSC grown at the optimal condition demonstrates a full-width at half-maximum of the (100) X-ray rocking curves of 0.0096°, a fluorescence lifetime of 1099 ns, a trap density of 4.5 × 109 cm–3, and a μτ product of 1.495 × 10–2 cm2 V–1. The resulting MAPbBr3 X-ray detector has a sensitivity of 2181 μC Gyair–1 cm–2. All results indicate that the controllable growth is beneficial to the crystal qualities and device performances. The concept proposed here will be inspiring for the community of researchers of perovskite materials.