A hydrophobic hole transporting oligothiophene for planar perovskite solar cells with improved stability - Zheng, Lingling; Chung, Yao-Hsien; Ma, Yingzhuang; Zhang, Lipei; Xiao, Lixin; Chen, Zhijian; Wang, Shufeng; Qu, Bo; Qihuang Gong (CHEMICAL COMMUNICATIONS, 2014)