An Intermediate-Temperature Biomass Fuel Cell Using Wood Sawdust and Pulp Directly as Fuel

Biomass is of significant interest in the field of advanced energy engineering, including the use of woody biomass as an energy source. However, because cellulose—the major component of wood—is insoluble in most solvents, an excessive amount of energy and special procedures are required to convert woody materials into liquid and gaseous fuel. This report describes a biomass fuel cell that provides power densities on the order of 10 mW cm −2 by direct utilization of wood sawdust and pulp as fuel. The fuel cell is simple, with H 3 PO 4 -impregnated raw materials located at the anode, and is operated at temperatures between 75 and 250°C. Cellulose or its decomposition products reacted with H 2 O to form CO 2 , where the coulombic yield was approximately 95% at 150°C or higher. Notably, the cell performance was superior to that of fuel cells with fuels (partially oxidized or dehydrated mono- to tetrasaccharides) obtained by an external treatment of cellulose with H 3 PO 4 .