Chemical Chelation-Assisted Highly Oriented Perovskite Solar Cells with Reduced Non-radiative Loss

Abstract

Shallow- and/or deep-level defects on perovskite surfaces and at grain boundaries serving as recombination centers can negatively affect photovoltaic device performance and stability, thus they need to be minimized. In this study, we modified perovskite films with furan-2,5-dicarboxylic acid (FDCA) to modulate perovskite crystallization and passivate multiple intrinsic shallow- and deep-level defects using an antisolvent method. Characterizations and density functional theory simulation were performed to investigate the coordination and hydrogen bonding interactions between FDCA and perovskite that led to oriented grains and reduced defects. The interactions between FDCA and perovskite reduced non-radiative recombination and improved charge transport. The FDCA-based solar cells exhibited a superior power conversion efficiency of over 24% with improved operation and storage stabilities. This passivation strategy reveals the mechanism behind the improvement of device performance.