Study of the catalysis and surface chemistry occurring at nickel/zirconia anodes in solid oxide fuel cells running on natural gas

Nickel-based/yttria-stabilised zirconia anodes for solid oxide fuel cells ( SOFCs) running on natural gas have been developed which show increased resi stance towards carbon deposition and improved durability. Surface carbon fo rmed on the anodes during reforming has been characterised using temperatur e programmed oxidation (TPO), The influence of anode composition and formul ation, pre-treatment method, operating temperature and methane/steam ratio have been studied. Doping the nickel/zirconia anode with small quantities o f molybdenum leads to a substantial reduction in the amount of carbon depos ited. As current is drawn from the SOFC increased methane conversion occurs together with reduced carbon deposition.