Lv Yifan, Zhang Hui, Liu Ruqing, Sun Yanan, Huang Wei
Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, P. R. China.
ACS Appl Mater Interfaces. 2020 Jun 17;12(24):27277-27285. doi: 10.1021/acsami.0c06823. Epub 2020 Jun 3.
Solar cells based on organometal hybrid perovskites have exhibited promising commercialization potential owing to their high efficiency and low-cost manufacturing. However, the poor outdoor operational stability of perovskite solar cells restricted their practical application, and moisture permeation and organic compounds volatilization are realized as the main factors accelerating performance degradation. Herein, we developed a composite encapsulation, by sequentially depositing a compact AlO layer and a hydrophobic 1,1,2,2-perfluorodecyltrichlorosilane layer on the completed device, to efficiently circumvent vapor permeability. Thus, the stability of the encapsulated perovskite solar cells was systematically investigated under simulated operational conditions. It was found that the MAPbI perovskite was prone to decay into solid PbI and organic vapor at high temperature or upon light illumination, and the decomposition was reversible in a well-encapsulated environment, resulting in reversible performance degradation and recovery. The enhanced thermal stability was ascribed to the competition between the perovskite decomposition and reverse synthesis. The as-prepared high-quality, multilayered encapsulation scheme demonstrated superior sealing property, and no obvious performance decline was observed when the device was stored under ambient air, continuous light illumination, double 85 condition (85 °C, 85% humidity), or even water immersion. Therefore, this work paves the way for a scalable and robust encapsulation strategy feasible to hybrid perovskite optoelectronics in a reproducible manner.
基于有机金属杂化钙钛矿的太阳能电池因其高效率和低成本制造而展现出了可观的商业化潜力。然而，钙钛矿太阳能电池较差的户外运行稳定性限制了其实际应用，水分渗透和有机化合物挥发被认为是加速性能退化的主要因素。在此，我们通过在完整器件上依次沉积致密的AlO层和疏水性的1,1,2,2-全氟癸基三氯硅烷层，开发了一种复合封装方法，以有效规避蒸汽渗透性。因此，在模拟运行条件下系统地研究了封装后的钙钛矿太阳能电池的稳定性。研究发现，MAPbI钙钛矿在高温或光照下容易分解为固态PbI和有机蒸汽，并且在良好封装的环境中这种分解是可逆的，导致性能出现可逆的退化和恢复。热稳定性的提高归因于钙钛矿分解与逆合成之间的竞争。所制备的高质量多层封装方案表现出优异的密封性能，当器件在环境空气中、持续光照、双85条件（85℃，85%湿度）甚至水浸条件下储存时，未观察到明显的性能下降。因此，这项工作为以可重复的方式实现适用于混合钙钛矿光电器件的可扩展且稳健的封装策略铺平了道路。
