This work describes the use of Self-Assembling Monolayer (SAM) to enhance the power conversion efficiencies of perovskite solar cells. The SAM molecules features of a –COOH functional group to anchor onto the ZnO surface and form favorable dipole moment for electron extraction, and a –NH2 group to provide an ammino rich surface for smooth crystalline growth of the CH3NH3PbI3 layer. As a result, the electronic coupling between the perovskite and ZnO is enhanced, and the crystalline properties of the perovskite film is also improved, which induces significant increase in the device power conversion efficiency (15.7%, highest).

Enhanced Photovoltaic Performance of CH₃NH₃PbI₃ Perovskite Solar Cells through Interfacial Engineering Using Self-Assembling Monolayer, Lijian Zuo , Zhuowei Gu , Tao Ye , Weifei Fu , Gang Wu , Hanying Li *, and Hongzheng Chen *, J. Am. Chem. Soc., 2015, 137 (7), pp 2674–2679