Dual-sites passivation for efficient and stable carbon-based perovskite solar cells

Abstract

It has been proven that dual-active-site passivation is more effective than single-site passivation in mitigating surface defects of carbon-based perovskite solar cells (C-PSCs). Therefore, it is imperative to explore new agents capable of inducing dual-active-site passivation effect. This work strategically employs potassium laurate (KLA) as a surface passivating agent, which stands out due to its extended saturated alkane chains and carboxylate groups, offering dual-active sites encompassing carboxylate ions and K+ cations. Carboxylate ions play a pivotal role in passivating low-coordinated Pb2+ defects, while K+ metal cations are anticipated to address anionic defects. The champion C-PSC achieves an impressive power conversion efficiency (PCE) of 16.10%, increased from 14.35% of the original. The incorporation of KLA serves to diminish surface defects within the film and suppress non-radiative recombination at the interface by dual-sites passivation, thereby establishing itself as a valuable technique for enhancing the efficiency and durability of C-PSCs.