混合溶剂蒸汽退火策略制备高效钙钛矿太阳能电池  

Mixed-solvent vapor annealing process in high-performance perovskite solar cell production

作　　者：杨光辉[1] 李德文 张冬华[3] YANG Guang-hui;LI De-wen;ZHANG Dong-hua(Jilin Provincial Institute of Education,Changchun 130022,China;No.3 High School of Changchun Automobile Economic and Technological Development Zone,Changchun 130011,China;Jilin Provincial Experimental School,Changchun 130022,China)

机构地区：[1]吉林省教育学院高中研训部,吉林长春130022 [2]长春汽车产业开发区第三中学,吉林长春130011 [3]吉林省实验中学,吉林长春130022

出　　处：《分子科学学报》2022年第6期486-492,共7页Journal of Molecular Science

基　　金：国家自然科学基金资助项目(21673036)。

摘　　要：制备高质量的钙钛矿薄膜对提升钙钛矿太阳能电池器件光伏性能至关重要,本文报道了一种异丙醇(IPA)和N,N-二甲基甲酰胺(DMF)混合溶剂蒸汽退火策略来改善钙钛矿薄膜质量,提升钙钛矿太阳能电池的光伏性能.首先通过两步法制备CH3NH3PbI3钙钛矿薄膜,并将制备好的薄膜分别置于无溶剂蒸汽、IPA溶剂蒸汽和IPA/DMF混合溶剂蒸汽气氛中进行热退火处理.测试结果表明IPA/DMF混合溶剂蒸汽退火可以增大钙钛矿晶粒尺寸、减少薄膜中的针孔、增强薄膜的光吸收能力、抑制非辐射复合,从而提升了相应钙钛矿太阳能电池的光电转换效率和长期稳定性.J-V测试结果表明在IPA/DMF混合溶剂蒸汽退火条件下所制备的器件效率可达到18.29%,与未经溶剂退火器件相比,该方法制备电池的效率提升了25%,迟滞效应基本消失,器件在空气环境中保存500 h后,效率仍保持其初始值的90%以上.In recent years, organic-inorganic hybrid perovskite materials have attracted extensive attention due to their excellent physical characteristics, such as high optical absorption coefficient, high carrier mobility, low exciton binding energy, and balanced bipolar carrier transport. However, solution-processed polycrystalline perovskite films inevitably contain some defects such as grain boundary and crystallographic defects. These defects hamper charge carrier transport, induce non-radiative recombination, and then leading to a reduction of device efficiency. Therefore, the preparation of high-quality perovskite thin films is crucial to improve the photovoltaic performance of perovskite solar cells(PSCs). In this paper, a mixed solvent vapor annealing strategy of isopropanol(IPA) and N,N-dimethylformamide(DMF) is reported to improve the quality of perovskite thin films and photovoltaic performance of PSCs. The PSCs adopted in this work are structured as FTO/TiO_(2)compact layer/perovskite layer/Spiro-OMeTAD/Ag, wherein TiO_(2)and Spiro-OMeTAD act as electron and hole transport layer, respectively. The CH3NH3PbI3perovskite films are prepared by a two-step method and the precursor films are thermal annealed in solvent free vapor, IPA solvent vapor and IPA/DMF mixed solvent vapor atmosphere, respectively. The samples fabricated using IPA/DMF mixed solvent vapor annealing method show a dense and uniform perovskite thin film layer on the electron transport layer. The improved film quality is attribute that the PbI2-MAI intermediate phase is slightly dissolved and recrystallized under the IPA/DMF mixed solvent vapor. The detailed characterization results demonstrate that IPA/DMF mixed solvent vapor annealing strategy increase the grain size of perovskite, reduce the pinholes, enhance crystallinity, inhibit the non-radiation recombination and enhance the light absorption capacity, resulting in improved power conversion efficiency and long-term stability of PSCs. The steady-state photoluminescence(PL) and time-resolved p

关 键 词：溶剂蒸汽退火 混合溶剂 MAPbI3薄膜 钙钛矿太阳能电池 

分 类 号：O649[理学—物理化学]