Meng Xiangyue, Wang Zheng, Qian Wei, Zhu Zonglong, Zhang Teng, Bai Yang, Hu Chen, Xiao Shuang, Yang Yinglong, Yang Shihe
Department of Chemistry , The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon , Hong Kong , China.
Guangdong Key Lab of Nano-Micro Material Research, School of Chemical Biology and Biotechnology , Peking University Shenzhen Graduate School , Shenzhen 518055 , China.
J Phys Chem Lett. 2019 Jan 17;10(2):194-199. doi: 10.1021/acs.jpclett.8b03742. Epub 2019 Jan 2.
We report an exploratory study on the crystal formation behavior of CsPbIBr perovskite films by adding excess cesium iodide (CsI). Surprisingly, facile co-crystallization of CsI and CsPbIBr in the form of spinodal decomposition is observed. Significantly, the two phases spontaneously form morphing into a remarkably uniform bicontinuous nanoscale blend with high orientational correlation through the well-matched (110) plane of CsI and the (200) plane of CsPbIBr. The CsPbIBr films produced by the spinodal decomposition method not only enjoy a compact surface, low defect concentration, and long carrier lifetimes, they also retain their excellent charge transport property. By employing such a CsPbIBr film for carbon-based perovskite solar cells, power conversion efficiency exceeding 10% is achieved with remarkable thermal stability. Our results provide valuable insight into the role of CsI in perovskite crystallization and a promising approach for designing inorganic halide perovskite-based devices.
我们报道了一项通过添加过量碘化铯（CsI）对CsPbIBr钙钛矿薄膜晶体形成行为的探索性研究。令人惊讶的是，观察到CsI和CsPbIBr以旋节线分解的形式轻松共结晶。值得注意的是，这两个相通过CsI的（110）平面和CsPbIBr的（200）平面良好匹配，自发形成变形为具有高度取向相关性的非常均匀的双连续纳米级混合物。通过旋节线分解法制备的CsPbIBr薄膜不仅具有致密的表面、低缺陷浓度和长载流子寿命，还保留了其优异的电荷传输性能。通过将这种CsPbIBr薄膜用于碳基钙钛矿太阳能电池，实现了超过10%的功率转换效率以及显著的热稳定性。我们的结果为CsI在钙钛矿结晶中的作用提供了有价值的见解，并为设计基于无机卤化物钙钛矿的器件提供了一种有前景的方法。
