Sensitive X-ray detection is crucial for medical diagnosis, industrial inspection and scientific research. The recently described hybrid lead halide perovskites have demonstrated low-cost fabrication and outstanding performance for direct X-ray detection, but they all contain toxic Pb in a soluble form. Here, we report sensitive X-ray detectors using solution-processed double perovskite Cs₂AgBiBr₆ single crystals. Through thermal annealing and surface treatment, we largely eliminate Ag⁺/Bi³⁺ disordering and improve the crystal resistivity, resulting in a detector with a minimum detectable dose rate as low as 59.7 nGy_air s⁻¹, comparable to the latest record of 0.036 μGy_air s⁻¹ using CH₃NH₃PbBr₃ single crystals. Suppressed ion migration in Cs₂AgBiBr₆ permits relatively large external bias, guaranteeing efficient charge collection without a substantial increase in noise current and thus enabling the low detection limit.

灵敏的X射线检测对于医学诊断，工业检查和科学研究至关重要。最近描述的杂化卤化铅钙钛矿已经证明了低成本制造和出色的直接X射线检测性能，但是它们都以可溶形式包含有毒的Pb。在这里，我们报告了使用溶液处理的钙钛矿双Cs ₂ AgBiBr ₆单晶体的灵敏X射线探测器。通过热退火和表面处理，我们在很大程度上消除了Ag ⁺ / Bi ^3+的无序性并提高了晶体电阻率，从而使检测器的最低可检测剂量率低至59.7 nGy_空气 s ^-1，与最新记录0.036相当甘氨酸使用CH ₃ NH ₃ PbBr ₃单晶的_空气 s ^-1。Cs ₂ AgBiBr _6中抑制的离子迁移允许相对较大的外部偏置，从而确保了有效的电荷收集，而不会显着增加噪声电流，从而实现了低检测限。