Low-Temperature Processed and Carbon-Based ZnO/CH<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub>/C Planar Heterojunction Perovskite Solar Cells ZhouHuawei ShiYantao WangKai DongQingshun BaiXiaogong XingYujin DuYi MaTingli 2015 Carbon-based ZnO/CH<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub>/C planar heterojunction perovskite solar cells (PHJ-PSCs) were prepared at low-temperature without using organic hole conductor and metal electrode. When measured via reverse bias scan, rigid and flexible PHJ-PSCs achieved power conversion efficiencies (PCEs) up to 8% and 4% on fluorine-doped tin oxide (FTO)/glass substrates and flexible polymer substrates, respectively. The flexible devices were capable of maintaining 80% of their initial PCEs after 1000 times of bending.