One-dimensional lead-free perovskite single crystals with high X-ray response grown by liquid phase diffusion

Abstract

Organic–inorganic hybrid bismuth halides, as essential members of the lead-free family, have attracted much attention due to their unique properties. However, the growth of bismuth-based single crystals with potentially low defect density has encountered many challenges, such as intractable rapid crystallization, the use of toxic organic solvents, and halide oxidation caused by prolonged heating. Herein, we developed a liquid phase diffusion method to prepare large-sized one-dimensional hybrid bismuth single crystals. Adopting this method, centimeter-sized (1,5-pentanediamine)BiI₅ single crystals were harvested, which possess a hole trap density as low as 1.31 × 10⁹ cm⁻³ and a carrier mobility reaching 28.2 cm² V⁻¹ s⁻¹. The X-ray detectors based on (1,5-pentanediamine)BiI₅ single crystals exhibit a sensitivity value of 8120 μC Gy_air⁻¹ cm⁻² at −80 V. This work provided a new strategy for the growth of bismuth-based perovskite single crystals and inspired the growth of other hybrid perovskite materials.