Thiosemicarbazide-complexed SnO2 electron transport layers for high-efficiency MAPbI3 perovskite solar cells

Abstract

High-quality electron transport layers (ETLs) are a crucial component of high-performance perovskite solar cells (PSCs) with the n–i–p configuration. Herein, a facile and effective way to improve the properties of SnO₂ ETLs is developed via introducing thiosemicarbazide (TSC) as a multifunctional additive. Due to the interaction between TSC and SnO₂ nanocrystals, the oxygen vacancies in SnO₂ could be effectively passivated, increasing the conductivity of SnO₂ ETLs. Moreover, the morphology of SnO₂ ETLs is improved and the wettability is also increased with TSC introduction, facilitating crystallization of perovskite films. Consequently, the PSCs based on TSC-complexed SnO₂ ETLs achieved a significant increase of power conversion efficiency with much reduced hysteresis and increased stability.