Department of Chemistry, Southern University of Science and Technology, SUSTech, Shenzhen, Guangdong, 518055, P.R. China.
College of Chemistry, Nankai University, Tianjin, 300071, P.R. China.
Angew Chem Int Ed Engl. 2017 Dec 11;56(50):15969-15973. doi: 10.1002/anie.201708684. Epub 2017 Nov 15.
Novel inorganic lead-free double perovskites with improved stability are regarded as alternatives to state-of-art hybrid lead halide perovskites in photovoltaic devices. The recently discovered Cs AgBiBr double perovskite exhibits attractive optical and electronic features, making it promising for various optoelectronic applications. However, its practical performance is hampered by the large band gap. In this work, remarkable band gap narrowing of Cs AgBiBr is, for the first time, achieved on inorganic photovoltaic double perovskites through high pressure treatments. Moreover, the narrowed band gap is partially retainable after releasing pressure, promoting its optoelectronic applications. This work not only provides novel insights into the structure-property relationship in lead-free double perovskites, but also offers new strategies for further development of advanced perovskite devices.
新型无机无铅双钙钛矿因其稳定性而被视为光电设备中最先进的混合卤化铅钙钛矿的替代品。最近发现的 CsAgBiBr 双钙钛矿具有吸引人的光学和电子特性，使其在各种光电应用中具有广阔的应用前景。然而，其实际性能受到大带隙的限制。在这项工作中，首次通过高压处理在无机光伏双钙钛矿中实现了 CsAgBiBr 的显著带隙缩小。此外，在释放压力后，部分缩小的带隙仍然可以保留，从而促进了其光电应用。这项工作不仅为无铅双钙钛矿的结构-性能关系提供了新的见解，也为先进钙钛矿器件的进一步发展提供了新的策略。
