Planar perovskite solar cells with 15.75% power conversion efficiency by cathode and anode interfacial modification

Anode modification by doping silver nano-particles (Ag NPs) into poly(3,4-ethylene dioxythiophene): poly(4-styrenesulfonate) (PEDOT: PSS) and cathode interfacial modification by inserting solution-processed bathophenanthroline (sBphen) in CH3NH3PbI3-xClx based planar perovskite solar cells are investigated. Prior to the optical effect such as localized surface plasmon resonance, the Ag-NPs distributed in PEDOT: PSS mainly cause an improvement in the electrical property of PEDOT: PSS-Ag NPs composite films. The sBphen interfacial layer modified the surface morphology of perovskite/phenyl-C-61-butyric acid methyl ester (PC61BM) films by filling the voids on the surface of perovskite/PC61BM effectively, which led to an obvious improvement in the fill factor. Accordingly, an efficient device with a power conversion efficiency of 15.75% was achieved due to the simultaneous cathode and anode interfacial modification.