Li Ning, Li Yuyang, Xie Shengdan, Wu Jinming, Liu Nianqiao, Yu Yuan, Lin Qinglian, Liu Yang, Yang Shuang, Lian Gang, Fang Yanjun, Yang Deren, Chen Zhaolai, Tao Xutang
State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, 250100, P. R. China.
State Key Laboratory of Silicon Materials and School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China.
Angew Chem Int Ed Engl. 2023 May 2;62(19):e202302435. doi: 10.1002/anie.202302435. Epub 2023 Mar 31.
Perovskite single crystals and polycrystalline films have complementary merits and deficiencies in X-ray detection and imaging. Herein, we report preparation of dense and smooth perovskite microcrystalline films with both merits of single crystals and polycrystalline films through polycrystal-induced growth and hot-pressing treatment (HPT). Utilizing polycrystalline films as seeds, multi-inch-sized microcrystalline films can be in situ grown on diverse substrates with maximum grain size reaching 100 μm, which endows the microcrystalline films with comparable carrier mobility-lifetime (μτ) product as single crystals. As a result, self-powered X-ray detectors with impressive sensitivity of 6.1×10 μC Gy cm and low detection limit of 1.5 nGy s are achieved, leading to high-contrast X-ray imaging at an ultra-low dose rate of 67 nGy s . Combining with the fast response speed (186 μs), this work may contribute to the development of perovskite-based low-dose X-ray imaging.
钙钛矿单晶和多晶薄膜在X射线检测和成像方面具有互补的优缺点。在此，我们报告了通过多晶诱导生长和热压处理（HPT）制备具有单晶和多晶薄膜优点的致密且光滑的钙钛矿微晶薄膜。以多晶薄膜为籽晶，可以在各种衬底上原位生长出多英寸尺寸的微晶薄膜，最大晶粒尺寸达到100 μm，这赋予了微晶薄膜与单晶相当的载流子迁移率-寿命（μτ）乘积。结果，实现了具有6.1×10 μC Gy cm的令人印象深刻的灵敏度和1.5 nGy s的低检测限的自供电X射线探测器，从而在67 nGy s的超低剂量率下实现了高对比度X射线成像。结合快速响应速度（186 μs），这项工作可能有助于基于钙钛矿的低剂量X射线成像的发展。
