Influence of a UV-ozone treatment on amorphous SnO2 electron selective layers for highly efficient planar MAPbI3 perovskite solar cells

• 作者: Kyungeun Jung Du Hyeon Kim Jaemin Kim Sunglim Ko Jae Won Choi Ki Chul Kim Sang-Geul Lee Man-Jong Lee
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2020,（24）
• 页码范围: 195-202
• 页数: 8页
• 语种: 英文

摘要

The effect of ultraviolet-ozone (UVO) irradiation on amorphous (am) SnO2 and its impact on the photo-conversion efficiency of MAPbl3-based perovskite solar cells were investigated in detail.UVO treatment was found to increase the amount of chemisorbed oxygen on the am-SnO2 surface,reducing the sur-face energy and contact angle.Physicochemical changes in the am-SnO2 surface lowered the Gibbs free energy for the densification of perovskite films and facilitated the formation of homogeneous perovskite grains.In addition,the Fermi energy of the UVO-treated am-SnO2 shifted upwards to achieve an ideal band offset for MAPbI3,which was verified by theoretical calculations based on the density functional theory.We achieved a champion efficiency of 19.01 ％ with a statistical reproducibility of 17.01 ± 1.34 ％owing to improved perovskite film densification and enhanced charge transport/extraction,which is con-siderably higher than the 13.78 ±2.15 ％ of the counterpart.Furthermore,UVO-treated,am-SnO2-based devices showed improved stability and less hysteresis,which is encouraging for the future application of up-scaled perovskite solar cells.