Molecular Engineering of Polymer Enabling Stability of Hybrid Perovskite Solar Cells

Abstract

How to inhibit the formation of point defects in the preparation process of hybrid perovskite for improving the stability and photovoltaic characteristics has been a hot research issue in recent years. Herein, molecular engineering of polyvinylpyrrolidone (PVP) is focused as a Lewis base for an additive to improve the interface matching of hybrid perovskite solar cells. Based on the molecular binding strategy, the film crystallinity, bond binding, interfacial transport, and water resistance can be effectively regulated, resulting in preferred photovoltaic characteristics. Herein, the highest photoelectric conversion efficiency of perovskite solar cells reaches 19.7% as well as the improved stability of solar cells. Moreover, combined with first‐principles calculation, the mechanism of PVP macromolecules inducing perovskite interfacial binding through molecular engineering is revealed, which provides a feasible route for using organic macromolecules to regulate the crystallinity and photovoltaic characteristics of hybrid perovskite devices.

Keywords

• bond binding
• interface matching
• molecular engineering
• thin-film solar cells