“Trash to Treasure” Recycling of Perovskite\nSingle Crystals for X‑ray Detection and Imaging

Organometal\nhalide perovskite single crystals (PSCs) have drawn\nintensive attention in X-ray detection due to their outstanding optoelectronic\nproperties. However, they currently suffer from a short lifespan caused\nby a phase transition or water and oxygen erosion. Sustainably recycling\nend-of-life PSCs is essential for reducing environmental impact and\nsaving costs on raw materials and time. Herein, we propose a “trash\nto treasure” economically recycling strategy, which utilizes\nammonium salt-assisted octahedral [PbI<sub>6</sub>]<sup>4–</sup> reconstruction and rearrangement to in situ treat various degraded\nPSCs. X-ray detectors based on the recycled PSCs demonstrate significantly\nenhanced performances comparable to those of previously reported fresh\nPSCs. For example, the recycled FAPbI<sub>3</sub> detectors show a\nhigh sensitivity of 4.32 × 10<sup>4</sup> μC Gy<sub>air</sub><sup>–1</sup> cm<sup>–2</sup> and a low limit of detection\nof 8.3 nGy<sub>air</sub> s<sup>–1</sup>, along with a high\nspatial resolution of 7.0 lp mm<sup>–1</sup>. Furthermore,\nthis method has also been successfully employed to construct 2D/3D\nheterojunctions. This method offers universality, effectiveness, and\nsimplicity, thereby inspiring the recycling and reuse of degraded\nperovskites.