A novel way to improve performance of proton-conducting solid-oxide fuel cells through enhanced chemical interaction of anode components

We proposed a novel way to improve the cell performance of proton-conducting solid-oxide fuel cells by increasing the chemical interaction between the anode components using BaZr_0.4Ce_0.4Y _0.2O_3-δ (BZCY4) as the ionic conducting phase of anode for a fuel cell with a BaCe_0.8Y_0.2O _3-δ (BCY) electrolyte. The strength of the chemical interaction between NiO and the ionic conducting phase (BZCY4 or BCY) was analyzed by the hydrogen temperature-programmed reduction (H₂-TPR) technique. The effect of chemical interaction between NiO and the ionic conducting phase on the NiO diffusivity was investigated by SEM-EDX. The results demonstrated NiO had a much stronger interaction with BZCY4 than with BCY, thereby resulting in suppressed diffusivity of NiO into the BCY electrolyte. Using BZCY4 as the ionic conducting phase of the anode, a cell with an ohmic resistance of 0.65 Ω cm² at 700 °C was obtained. In contrast, a cell with BCY as the ionic conducting phase of the anode had an ohmic resistance of 0.82 Ω cm² at 700 °C. Therefore, the single cell with NiO + BZCY4 anode showed a peak power density higher than that of the cell with the NiO + BCY anode.