Hierarchically Porous Network‐Like Ni/Co₃O₄: Noble Metal‐Free Catalysts for Carbon Dioxide Methanation

Abstract The impasse always present regarding catalysts for energy conversion reactions is that noble metals with promising activity are limited by their high price and scarcity, whereas base metals with a lower price show moderate activity performance. Herein, a purely transition metal‐based, Ni‐promoted 3D draped porous Co₃O₄ (Ni/3DDP‐Co₃O₄) catalyst is demonstrated to be highly effective for CO₂ methanation, achieving 100% CO₂ conversion and CH₄ selectivity at 250 °C and a space velocity of 48 000 mL (g h)⁻¹. Dispersing Ni nanodeposits on the large surface of the 3DDP‐Co₃O₄ promotes a 2.6 times increase in reaction rate and a 20% drop in apparent activation energy relative to 3DDP‐Co₃O₄. An abundance of surface oxygen vacancies extrinsically forms on the Ni/3DDP‐Co₃O₄ by both Co–Ni charge‐compensating mechanisms and hydrogen treatment, in conjunction with the low‐temperature reducibility, high surface area, and strong Co–Ni interaction effect, enabling the enhanced catalytic performance for CO₂ methanation.