Design of a Monolithic Photoelectrochemical Tandem Cell for Solar Water Splitting with a Dye-sensitized Solar Cell and WO3/BiVO4 Photoanode

Abstract

Photoelectrochemical cell (PEC) is one of the attractive ways to produce clean and renewable energy. However, solar to hydrogen production via PEC system generally requires high external bias, because of material’s innate electronic band potential relative to hydrogen reduction potential and/or charge separation issue. For spontaneous photo-water splitting, here, we design dye-sensitized solar cell (DSSC) and their monolithic tandem cell incorporated with a BiVO4 photoanode. BiVO4 has high conduction band edge potential and suitable band gap (2.4eV) to absorb visible light. To achieve efficient BiVO4 photoanode system, electron and hole mobility should be improved, and we demonstrate a tandem cell in which BiVO4/WO3 film is connected to cobalt complex based DSSC.