Fuel reforming and electrical performance studies in intermediate temperature ceriagadolinia-based SOFCs

摘要

The methane reforming and carbon deposition characteristics of two nickel/ceria--gadolinia cermet anodes have been studied over the temperature range 550--700deg. C, for use in intermediate temperature ceria--gadolinia (CGO)-based solid oxide fuel ce1ls (SOFCs), using conventional catalytic methods and temperature-programmed spectro scopy. The e1ectric al performance and durability of planar CGO~based SOFCs with a 280-μm-thick CGO electrolyte, screen printed cathode and different screen printed nickel/CGO cermet anodes have been studied over the temperature range 500--650deg. C. Temperature-programmed reduction has been used to study the reduction characteristics of the anodes, and indicates the presence of "bulk" NiO particles and smaller NiO particles in intimate contact with the ceria. Both anodes show good activity towards methane steam reforming with methane activation occurring at temperatures as 1ow as 2l0deg. C; steady-state steam reforming of methane was observed using a methane-rich mixture at 650deg. C, with 20/100 methane conversion. Post-reaction temperature -programm oxidation has been used to determine the amount of carbon deposited during reforming and the strength of its interaction with the anode.