Direct oxidation of hydrocarbons in a solid-oxide fuel cell

The direct electrochemical oxidation of dry hydrocarbon fuels to generate e lectrical power has the potential to accelerate substantially the use of fu el cells in transportation and distributed-power applications(1). Most fuel -cell research has involved the use of hydrogen as the fuel, although the p ractical generation and storage of hydrogen remains an important technologi cal hurdle(2). Methane has been successfully oxidized electrochemically(3-6 ), but the susceptibility to carbon formation from other hydrocarbons that may be present or poor power densities have prevented the application of th is simple fuel in practical applications(1). Here we report the direct, ele ctrochemical oxidation of various hydrocarbons (methane, ethane, 1-butene, n-butane and toluene) using a solid-oxide fuel cell at 973 and 1,073 K with a composite anode of copper and ceria (or samaria-doped ceria). We demonst rate that the final products of the oxidation are CO2 and water, and that r easonable power densities can be achieved. The observation that a solid-oxi de fuel cell can be operated on dry hydrocarbons, including liquid fuels, w ithout reforming suggests that this type of fuel cell could provide an alte rnative to hydrogen-based fuel-cell technologies.