Zhu Xuejie, Du Minyong, Feng Jiangshan, Wang Hui, Xu Zhuo, Wang Likun, Zuo Shengnan, Wang Chenyu, Wang Ziyu, Zhang Cong, Ren Xiaodong, Priya Shashank, Yang Dong, Liu Shengzhong Frank
Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, 710119, China.
Dalian National Laboratory for Clean Energy, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, 116023, China.
Angew Chem Int Ed Engl. 2021 Feb 19;60(8):4238-4244. doi: 10.1002/anie.202010987. Epub 2020 Dec 23.
Surface defects have been a key constraint for perovskite photovoltaics. Herein, 1,3-dimethyl-3-imidazolium hexafluorophosphate (DMIMPF ) ionic liquid (IL) is adopted to passivate the surface of a formamidinium-cesium lead iodide perovskite (Cs FA PbI ) and also reduce the energy barrier between the perovskite and hole transport layer. Theoretical simulations and experimental results demonstrate that Pb-cluster and Pb-I antisite defects can be effectively passivated by [DMIM] bonding with the Pb ion on the perovskite surface, leading to significantly suppressed non-radiative recombination. As a result, the solar cell efficiency was increased to 23.25 % from 21.09 %. Meanwhile, the DMIMPF -treated perovskite device demonstrated long-term stability because the hydrophobic DMIMPF layer blocked moisture permeation.
表面缺陷一直是钙钛矿光伏领域的关键制约因素。在此，采用1,3-二甲基-3-咪唑鎓六氟磷酸盐（DMIMPF ）离子液体（IL）对甲脒铯铅碘化物钙钛矿（Cs FA PbI ）的表面进行钝化，并降低钙钛矿与空穴传输层之间的能垒。理论模拟和实验结果表明，[DMIM]与钙钛矿表面的Pb离子键合可有效钝化Pb簇和Pb-I反位缺陷，从而显著抑制非辐射复合。结果，太阳能电池效率从21.09 %提高到了23.25 %。同时，经DMIMPF处理的钙钛矿器件表现出长期稳定性，因为疏水性的DMIMPF层阻止了水分渗透。
