Organic-inorganic hybrid electron transport layer of PVP-doped SnO2 for high-efficiency stable perovskite solar cells

Abstract

SnO 2 is one of the most popular low-cost inorganic electron transport materials for perovskite solar cells. However, the agglomeration of SnO 2 nanoparticles causes their uneven distribution and the existence of pinholes, seriously hindering the electron migration across SnO 2 /perovskite interface and limiting the device performance. The poor wettability between the SnO 2 film and the perovskite precursor solution also impairs the growth of perovskite grains. In this work, an innovative strategy was employed to produce an organic-inorganic hybrid electron transport layer (ETL) by fabricating a high-quality polyvinylpyrrolidone (PVP)/SnO 2 perovskite film with few defects and good wettability. In turn, a PVP-SnO 2 based device exhibits elevated power conversion efficiency (PCE) (18.98%) and adequate reproducibility along with superior operational stability. •A dense and smooth inorganic ETL PVP-SnO 2 with few defects and perfect wettability has been obtained. •The morphology-regulation for perovskite film has been further optimized. •Highefficiency and stability of PSCs can be further enhanced by employing the ETL PVP-SnO 2 .