Min Xiao, Shuai Gu, Pengchen Zhu, Mingyao Tang, Weidong Zhu, Renxing Lin, Chuanlu Chen, Weichao Xu, Tao Yu, and Jia Zhu*. "Tin-Based Perovskite with Improved Coverage and Crystallinity through Tin-Fluoride-Assisted Heterogeneous Nucleation", Adv. Opt. Mater.,1700615 （2017）.