Performance Improvement of Oxide Catalyst-doped Anode Supported SOFCs for Methane Fuel

Abstract

Solid oxide fuel cells (SOFCs) with a conventional Ni cermet anode suffer carbon deposition when directly used with hydrocarbon fuels. In this work, oxide catalysts containing Li2TiO3, which can prevent carbon deposition, were developed and the performance of catalyst-doped anode-supported SOFCs for use with CH4 fuel was evaluated. Li2TiO3 catalyst synthesized at 700oC for 24 h by a solid state reaction method showed excellent resistance to carbon deposition on Li2TiO3 catalyst-doped Ni-YSZ anodes. Our SOFC unit cells were manufactured by laminating catalyst-doped Ni-YSZ anodes and YSZ electrolytes prepared via tape-casting followed by co-sintering the laminate at 1325oC, screen-printing the LSM-YSZ cathode on the YSZ electrolyte, and sintering at 1150oC. The power density of the catalyst-doped Ni-YSZ anode-supported unit cells was higher than 0.4 W/cm2 at 800oC and, in particular, their long-term stability improved considerably when used with CH4 fuel.