Solution processed double-decked V2Ox/PEDOT: PSS film serves as the hole transport layer of an inverted planar perovskite solar cell with high performance

In this paper, we have reported a high-performance inverted planar perovskite solar cell (PSC) with double-decked hole transport layer (HTL) sandwiched between the indium tin oxide (ITO) electrode and the perovskite photoactive layer. The double-decked HTL film is fabricated by coating inorganic vanadium oxide (V(2)Ox) layer and poly(3,4-ethylene-dioxy-thiophene)-poly(styrene sulfonate) (PEDOT: PSS) layer. In this study, double-decked V2Ox/PEDOT: PSS HTL film can improve the optoelectronic properties of PSC device. It has been found that the double-decked V2Ox/PEDOT: PSS film plays a crucial role in enhancing charge transfer rate and suppressing electron-hole pair recombination. The valence of vanadium in the V2Ox has been changed by adjusting the molar ratio of V2O5 to H2O2. The PSC can reach its best performance when V2O5 and H2O2 react at a molar ratio of 1 : 60. In addition, the concentration of the V2Ox aqueous solution has also been changed to optimize performance of PSC. Hence, the device with double-decked V2Ox/PEDOT: PSS HTL film can increase the power conversion efficiency (PCE) to 15.86%, higher than that of reference device with PEDOT: PSS (13.56%). Besides, compared with reference device, our device has a better repeatability in the preparation process.