Interface-Tension-Assisted Temperature-Gradient Crystallization of High-Quality MAPbBr₃ Perovskite Single Crystals with Low Defect Densities

Comprehensive understanding and precise manipulation of the crystallization process for organic–inorganic hybrid perovskite materials are crucial for advancing perovskite single-crystal optoelectronic technology. In this study, we theoretically and experimentally investigated the influence of interface tension on the synthesis of perovskite single crystals. On the basis of the understanding of the nucleation and growth mechanisms, we developed a polydimethylsiloxane-assisted temperature-gradient growth technique to prepare high-quality MAPbBr₃ single crystals. Using this technique, we harvested some high-quality MAPbBr₃ single crystals, with the narrowest reported full width at half-maximum (0.00806°) of X-ray diffraction rocking curve, the longest carrier lifetime of 1002 ns, and an ultralow trap-state density of 4.25 × 10⁹ cm^–3. Furthermore, the X-ray detector fabricated using our MAPbBr₃ single crystal exhibited a high sensitivity of 7275 μC Gy^1– cm² and a low minimum detection limit of 0.67 μGy s^–1. This paper presents a novel method to control the crystallization and growth processes of high-quality perovskite single crystals.