纳米技术
化学物理
纳米晶
单层
纳米结构
自组装
化学工程
纳米颗粒
纳米尺度
量子点
作者
Yurou Zhang,Dohyung Kim,Jung-Ho Yun,Jongchul Lim,Min-Cherl Jung,Xiaoming Wen,Jan Seidel,Eunyoung Choi,Mu Xiao,Tengfei Qiu,Miaoqiang Lyu,Ekyu Han,Mehri Ghasemi,Sean Lim,Henry J. Snaith,Jae Sung Yun,Lianzhou Wang
标识
DOI:10.1002/adfm.202105542
摘要
Organometal perovskite single crystals have been recognized as a promising platform for high-performance optoelectronic devices, featuring high crystallinity and stability. However, a high trap density and structural nonuniformity at the surface have been major barriers to the progress of single crystal-based optoelectronic devices. Here, the formation of a unique nanoisland structure is reported at the surface of the facet-controlled cuboid MAPbI(3) (MA = CH3NH3+) single crystals through a cation interdiffusion process enabled by energetically vaporized CsI. The interdiffusion of mobile ions between the bulk and the surface is triggered by thermally activated CsI vapor, which reconstructs the surface that is rich in MA and CsI with reduced dangling bonds. Simultaneously, an array of Cs-Pb-rich nanoislands is constructed on the surface of the MAPbI(3) single crystals. This newly reconstructed nanoisland surface enhances the light absorbance over 50% and increases the charge carrier mobility from 56 to 93 cm(2) V-1 s(-1). As confirmed by Kelvin probe force microscopy, the nanoislands form a gradient band bending that prevents recombination of excess carriers, and thus, enhances lateral carrier transport properties. This unique engineering of the single crystal surface provides a pathway towards developing high-quality perovskite single-crystal surface for optoelectronic applications.
科研通智能强力驱动
Strongly Powered by AbleSci AI