Improved performance of solid-state dye-sensitized solar cells with p/p-type nanocomposite electrolyte

A high charge conductivity of p/p nanocomposite PEDOT–PSS/CuI, by in situ deposition of CuI nanocrystals on the surfaces of PEDOT–PSS (poly(3,4-ethylenedioxy-thiophene)–poly(styrenesulphonate)) colloidal nanoparticles has been prepared, for the first time, to fabricate novel solid-state dye-sensitized solar cells. The p-type CuI on the surface of PEDOT–PSS particles and its electrochemical properties were investigated by the transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry measurement (CV). The increased charge transport conductivity (σ) and the highest occupied molecular orbital energy levels (EHOMO) were dominated by the p-type CuI in the nanocomposites. By doping CuI in the hole-transporting layer, a noticeable power conversion efficiency has been achieved compared to the solid-state DSCs with PEDOT–PSS, which shown that the p/p-type nanocomposites could be successfully used to construct practical potentials in solid-state DSCs.