Hydrothermally synthesized NiO-samarium doped ceria nano-composite as an anode material for intermediate-temperature solid oxide fuel cells

NiO-Ce_0.8Sm_0.2O_1.9 (Ni-SDC) composite anode powders are synthesized with a hydrothermal technique. The average size of the particles in the anode powder is about 10 nm. Different phases distribute uniformly in the composite. The anode sintered at 700 °C exhibits an electrical conductivity of above 100 S cm⁻¹, three orders of magnitude higher than that of a similar solid-mixed composite anode with the same composition. The anode synthesized through the hydrothermal process also possesses a higher catalytic activity. An SDC-carbonate composite electrolyte-supported single cell with the composite anode exhibits a maximum power density of 738 mW cm⁻² at 700 °C with H₂ as fuel, much higher than that of a similar cell with a solid-mixed anode. The cell also exhibits a promising stability with methanol as fuel.