Collateral hydrogenation over proton-conducting Ni/BaZrYO catalysts for promoting CO methanation.

Despite the importance of CO methanation for eco-friendly carbon-neutral fuel recycling, the current technologies, relying on catalytic hydrogenation over metal-based catalysts, face technological and economical limitations. Herein, we employ the steam hydrogenation capability of proton conductors to achieve collateral CO methanation over the Ni/BaZrYO catalyst, which is shown to outperform its conventional Ni/AlO counterpart in terms of CH yield (8% higher) and long-term stability (3% higher for 150 h) at 400 °C while exhibiting a CH selectivity above 98%. Moreover, infrared and X-ray photoelectron spectroscopy analyses reveal the appearance of distinct mobile proton-related OH bands during the methanation reaction.