Solution-processed vanadium oxide thin film as the hole extraction layer for efficient hysteresis-free perovskite hybrid solar cells

Abstract In this study, we report a simple way to fabricate VO x thin film from pure-water solution, as the hole extraction layer (HEL) for perovskite hybrid solar cells (pero-HSCs). Furthermore, an aminopropanoic acid (APPA) interfacial layer is used to modify VO x thin film for reducing the charge carrier recombination rate. As a result, the pero-HSCs with the VO x /APPA HEL exhibits better device performance than that of the pero-HSCs with the VO x HEL and the pero-HSCs with poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonate) HEL. Moreover, the pero-HSCs with the VO x /APPA HEL exhibits hysteresis-free characteristics. All these results indicate that we report a simple approach to realize high performance of perovskite hybrid solar cells.