Interface Engineering for Highly Efficient and Stable Perovskite Solar Cells

Abstract The ongoing global research and development efforts on perovskite solar cells (PSCs) have led the power conversion efficiency to a high record of 26.1%. The optimization of PSC processing methods, the development of new compositions, and the introduction of passivation strategies are key factors behind the meteoric rise in performance. In particular, defect passivation and mitigation of ion migration via molecular engineering of the interfaces have played a critical role in enhancing the photovoltaic performance and operational stability of PSCs. The key interface engineering strategies enabling highly stable and efficient PSCs are focused here. The interface chemistry and the deleterious impact associated with it are discussed. The molecular design of effective modulators to mitigate the negative effects of perovskite interfaces is elaborated along with advanced characterization techniques to probe the interfaces. The progress of interface modification by multiple strategies is presented, and different modulator designs that are proven to be effective in mitigating the negative effects of perovskite interfaces are highlighted. Moreover, the main properties of effective interface modification strategies are summarized, and general design principles are deduced for future applications. Here, important insights are provided into the fields of material chemistry, physical chemistry, and optoelectronics.