Inside Front Cover

Shihuai Wang and co‐workers employ a perylene diimide as the interfacial material to passivate surface defects of perovskite and thus improve the performance of perovskite solar cells. They firstly found that the introduction of interfacial material between perovskite layer and hole‐transport layer could enhance the electron transfer across electron transport layer interface more efficiently. The rights of cover image belong to Prof. Yong Hua. image