Growth window optimization for large-size quasi-two-dimensional Dion–Jacobson type perovskites

Quasi-2D DJ type perovskites theoretically offer excellent properties for X-ray detection, but they often face issues such as phase segregation and small crystal size. In this study, we synthesized large single crystals of quasi-2D DJ type perovskite (3AMPY)(MA)Pb₂Br₇ using temperature-controlled crystallization. The resulting X-ray detector exhibited high resistivity (1.78 × 10⁹ Ω cm), a carrier mobility-lifetime (<i>μτ</i>) product of 9.32 × 10^-4 cm² V^-1, a dark current of 5.6 × 10^-8 A cm^-2 V^-1, and a sensitivity of 129.86 μC Gy^-1 cm^-2. These results demonstrate the potential of quasi-2D DJ type perovskites for high-performance X-ray detection and provide insights into improving crystal growth for optoelectronic applications.