A direct carbon fuel cell with a CuO–ZnO–SDC composite anode

Abstract

A direct carbon fuel cell with a copper oxide–zinc oxide–Sm_0.2Ce_0.8O_2−x (CuO–ZnO–SDC) composite anode was demonstrated. Nano-sized SDC and CuO–ZnO were synthesized by utilizing a co-precipitation process and a solid state reaction, respectively. As-prepared materials were characterized by various techniques, and then used to fabricate single cells by a co-press and co-sintering method. Finally, a button cell was tested with a mixture of carbon black and ternary (Li, Na, and K) eutectic carbonates as the anode fuel. The inert environment of the anode compartment was protected by pure N₂ or a mixture of N₂ & CO₂. A maximum power density of 130 mW cm⁻² was achieved using the mixture of N₂ & CO₂ as the anode gas at 700 °C. The results indicate that CuO–ZnO can be used as a nickel-free anode material for direct carbon fuel cells. Also, the modified anode gas of a N₂ & CO₂ mixture can enhance the performance of direct carbon fuel cells with a CuO–ZnO–SDC composite anode.