Exploring the film growth in perovskite solar cells

Abstract

In the past ten years, perovskite solar cells (PSCs) have shown great potential for development, with their maximum power conversion efficiency (PCE) reaching 25.5%. However, poor perovskite films with low coverage, pores, and small grain size are often obtained in the actual preparation process. These issues not only make it more difficult to achieve a high PCE, but also lead to the easy decomposition of films in the environment. A fast nucleation rate and low crystallinity are main reasons for the poor film quality. Therefore, it is possible to control factors that affect the growth of perovskite films to obtain high-quality films. Here, we first introduce the theoretical mechanism of film nucleation and growth. Afterwards, some main influencing factors in the growth of perovskite films are summarized, including the choice of substrate materials, annealing process, precursor composition, additive engineering and solvent engineering. Next, we present some insight into the growth of 2D and 2D/3D mixed perovskite films. Finally, we propose some views on the future development of PSCs.