The impact at polar solvent treatment on p-contact layers (PEDOT:PSS or NiO_x) of hybrid perovskite solar cells

This is work investigates that the effect of polar solvents on the hole transport layer PEDOT:PSS and NiO_x. Since perovskite precursor solution is typically prepared from polar solvents, understanding the effect of polar solvents treatment of the PEDOT:PSS layer on the performance of perovskite solar cells is important for device processing optimization. Here, the influence of the surface treatment of the PEDOT:PSS layer with solvents, including dimethyl sulfoxide (DMSO), and γ-butyrolactone (GBL), on the device performance of perovskite solar cells was investigated. Increased conductivity was measured for the PEDOT:PSS film after solvent treatments, which was ascribed to the partial removal of the PSS component from the PEDOT:PSS layer, as evidenced by photoluminescence spectroscopy, UV–vis absorption spectroscopy and XPS spectroscopy. In comparison with the reference cell, poorer device performance was obtained for the perovskite solar cells directly deposited on the solvent washed PEDOT:PSS film. Finally, PEDOT:PSS was replaced by NiOx as a hole transport layer, so successful fabrication of the device won't be affected by polar solvents.