Al2O3-coated nanoporous TiO2 electrode for solid-state dye-sensitized solar cell

This paper reports the preparation of a core-shell nanoporous electrode consisting of an inner TiO2 porous matrix and a thin overlayer of Al2O3, and its application for solid-state dye-sensitized solar cell using p-CuI as hole conductor. Al2O3 overlayer was coated onto TiO2 porous film by the surface sol–gel process. The role of Al2O3 layer thickness on the cell performance was investigated. The solar cells fabricated from Al2O3-coated electrodes showed superior performance to the bare TiO2 electrode. Under illumination of AM 1.5 simulated sunlight (89 mW/cm2), a ca. 0.19 nm Al2O3 overlayer increased the photo-to-electric conversion efficiency from 1.94% to 2.59%.