LAUSR

A photo‐assisted fuel cell (photofuel cell; PFC) consisting of a porous TiO2 photoanode and a Pt cathode in an aqueous electrolyte containing an organic fuel has been developed to generate an electric power by photoelectrochemically decomposing the fuel. Although direct utilization of cellulose as a fuel should be preferable, photocatalytic direct decomposition of cellulose, polymeric macromolecules, has been rarely reported. In the present study, a cellulose thin film deposited onto the TiO2 photoanode was used as the fuel. It was revealed that the cellulose was decomposed into CO2 through small carbonyl hydrocarbon intermediates. The complete decomposition of cellulose into CO2 implies that almost all the Gibbs free energy of cellulose can be converted into an electric power with the assistance of the photon energy. The PFC composed of the cellulose‐deposited TiO2 and Pt‐deposited Ni foam exhibited excellent photovoltaic performances (1.1 V of photovoltage and quantum efficiency up to 52 %). The present study should represent a potential means of electric power generation based on renewable energy sources by effectively treating waste biomass.