Researchers at the Georgia Institute of Technology, United States, have developed a self-cleaning technique that could allow solid oxide fuel cells to be powered directly by coal gas at operating temperatures as low as 750 degrees Celsius. The technique, which uses barium oxide nanoparticles, could provide a cleaner and more efficient alternative to conventional power plants that generate electricity from coal. Conventional solid oxide fuel cells rely on anodes from nickel and a ceramic material know as yttria-stabilized zirconia, but carbon-containing fuels such as coal gas can deactivate these anodes, clogging them with carbon deposits in a process known as “coking”. Using the barium oxide nanostructures on the anodes keeps the nickel electrode surfaces clean even when carbon-containing fuels are used at lower temperatures. According to Meilin Liu, a professor of materials science and engineering, “This could ultimately be the cleanest, most efficient and cost-effective way of converting coal into electricity. And by providing an exhaust stream of pure carbon dioxide, this technique could also facilitate carbon sequestration without the separation and purification steps now required for conventional coal-burning power plants.” The technique was reported in the journal Nature Communications.