Fabrication and operation of flow‐through tubular SOFCs for electric power and synthesis gas cogeneration from methane

Flow‐through type tubular solid oxide fuel cells were successfully fabricated and operated with a single‐chamber configuration for realizing the simultaneous generation of electric power and synthesis gas from methane by integrating a downstream catalyst into the fuel cell reactor. A new operation mode, which completely eliminated the gas diffusion between cathode side and anode side, is proposed. The cell showed high open‐circuit voltages of 1.02–1.08 V at the furnace temperature range of 650–800°C when operating on CH4‐O2 gas mixture at a molar ratio of 2:1. A peak power density of approximately 300 mW cm−2 and a maximum power output of 1.5 W were achieved for a single cell with an effective cathode geometric surface area of 5.4 cm2 at the furnace temperature of 750°C. The in‐situ initialization of the cell using CH4‐O2 gas mixture was also realized via applying an effective catalyst into the tubular cell.