Solvent Selection of All-Inorganic Perovskite Single Crystals for High Sensitivity and Operational Stability X-ray Detection

Solution-based anisotropic growth of fully inorganic metal halide perovskite single crystals, CsPbBr3, presents significant challenges to its development in X-ray detection, which typically requires the addition of solid additives to balance the growth rates of different crystallographic facets. However, the introduction of such additives often leads to lattice doping and the excessive incorporation of halide ions. In this work, we developed an innovative solvent engineering strategy that regulates the deposition rate of PbBr2 through the differential coordination capabilities of solvent molecules with PbBr2. This approach enables the balanced growth rates of high-quality CsPbBr3 single crystals, and no other ions like organic and other halogen ions will be introduced. As a result, we successfully fabricated large, transparent CsPbBr3 single crystals with dimensions of 1.5 × 1.5 × 0.9 cm3, achieving a defect state density of 4.89 × 109 cm–3, comparable to that of single crystals grown by the Bridgman method. The fabricated vertical devices achieve a sensitivity of 44,760 μC·Gyair–1·cm–2 and a limit of detection dose rate of 29.84 nGy·s–1. Furthermore, this solvent engineering strategy mitigated ionic migration in the device. After 48 h of high temperature accelerated aging test and then 600 rad radiation aging test, the current baseline shift of the detector was negligible.