Halide perovskites (HPs) have demonstrated excellent direct X-ray detection performance. Lead-free perovskite polycrystalline wafers have outstanding advantages in large-area X-ray imaging applications due to their area-scalability, thickness-controllability, large bulk resistivity, and ease of integration with large-area thin film transistor arrays. However, currently lead-free perovskite polycrystalline wafers possess low sensitivity, typically less than 1000 µC Gy⁻¹ cm⁻², which severely limits their X-ray detection applications. Here, high-quality and large scale polycrystalline wafers of AG₃Bi₂I₉ (AG: aminoguanidinium) with short intercluster distances are successfully prepared using a hot-pressing method. The wafers possess high mobility-lifetime product of 5.66 × 10⁻³ cm² V⁻¹ and therefore achieve high X-ray sensitivity of 2675 µC Gy⁻¹ cm⁻², which can be comparable to those of the high-quality single crystal counterpart reported by the previous research (7.94 × 10⁻³ cm² V⁻¹ and 5791 µC Gy⁻¹ cm⁻²), and represent the best results of the currently lead-free HP polycrystalline wafers. Besides, the wafers exhibit the X-ray detection limit as low as 11.8 nGy s⁻¹, excellent long-term working stability, and high spatial resolution of 5.9 lp mm⁻¹ in imaging. The findings demonstrate that AG₃Bi₂I₉ polycrystalline wafers are feasible for high-performance X-ray detection and imaging system.

中文翻译：

---

通过热压策略实现高性能 X 射线检测的大规模无铅钙钛矿多晶晶片


卤化物钙钛矿 （HPs） 已表现出优异的直接 X 射线检测性能。无铅钙钛矿多晶晶片具有面积可扩展性、厚度可控性、大体电阻率以及易于与大面积薄膜晶体管阵列集成等特点，在大面积 X 射线成像应用中具有突出优势。然而，目前无铅钙钛矿多晶晶片的灵敏度较低，通常小于 1000 μC ^{Gy-1 cm-2}，这严重限制了它们的 X 射线检测应用。在这里，使用热压方法成功制备了具有短簇间距离的 AG₃Bi₂I₉（AG：氨基胍）的高质量和大规模多晶晶片。晶圆具有 5.66 × ^10-3 cm^{2 V-1} 的高迁移率寿命积，因此实现了 2675 μC ^{Gy-1 cm-2} 的高 X 射线灵敏度，可以与先前研究报道的高质量单晶相当（7.94 × 10-3 cm^{2 V-1} 和 5791 μC ^{Gy-1 cm-2}），代表了目前无铅 HP 多晶硅片的最佳结果。此外，晶片的 X 射线检出限低至 11.8 nGy ^s-1，出色的长期工作稳定性，以及 5.9 lp ^mm-1 的高空间分辨率成像。研究结果表明，AG₃Bi₂I₉ 多晶晶片可用于高性能 X 射线探测和成像系统。