Sequential Growth of 2D/3D Double‐Layer Perovskite Films with Superior X‐Ray Detection Performance

Advanced Science

Shuang Xiao¹  Jian Wang¹  Wei Qian¹  Shihe Yang¹  Xiuwen Xu¹  Jiecheng Yang²  Yongshuai Ge²  Jianwei Chen² 

[1] Guangdong Key Lab of Nano‐Micro Material Research School of Chemical Biology and Biotechnology Shenzhen Graduate School Peking University Shenzhen 518055 China;Research Center for Medical Artificial Intelligence Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 China;

关键词: direct X‐ray detection;    interfacial engineering;    low‐dimensional perovskites;   

DOI  :  10.1002/advs.202102730

来源: DOAJ

【 摘 要 】

Abstract Perovskite materials in different dimensions show great potential in direct X‐ray detection, but each with limitations stemming from its own intrinsic properties. Particularly, the sensitivity of two‐dimensional (2D) perovskites is limited by poor carrier transport while ion migration in three‐dimensional (3D) perovskites causes the baseline drifting problem. To circumvent these limitations, herein a double‐layer perovskite film is developed with properly aligned energy level, where 2D (PEA)2MA3Pb4I13 (PEA=2‐phenylethylammonium, MA=methylammonium) is cascaded with vertically crystallized 3D MAPbI3. In this new design paradigm, the 3D layer ensures fast carrier transport while the 2D layer mitigates ion migration, thus offering a high sensitivity and a greatly stabilized baseline. Besides, the 2D layer increases the film resistivity and enlarges the energy barrier for hole injection without compromising carrier extraction. Consequently, the double‐layer perovskite detector delivers a high sensitivity (1.95 × 104 μC Gyair−1 cm−2) and a low detection limit (480 nGyair s−1). Also demonstrated is the X‐ray imaging capacity using a circuit board as the object. This work opens up a new avenue for enhancing X‐ray detection performance via cascade assembly of various perovskites with complementary properties.

【 授权许可】

Unknown