Construction of Co3O4/Pt Catalyst with Interfacial N-Stabilized Co3+-OH-Pt Pair for Highly Efficient CO2 Methanation

Graphical This study investigates N -doped Co 3 O 4 /Pt catalysts synthesized using a Pt-decorated ZIF-67 sacrificial template, followed by a water-soaking treatment to enhance surface hydroxyl (-OH) group content. The interfacial N -stabilized Co 3+ -OH-Pt active sites in N -Co 3 O 4 /Pt improved synergy between cobalt and platinum, enhancing agglomeration resistance and enhancing catalytic performance. CO 2 hydrogenation is a promising method for converting CO 2 into valuable products. Cobalt-based catalysts are favored for their low cost and high activity, but they face challenges from sintering-induced deactivation. This study investigates N -doped Co 3 O 4 /Pt catalysts synthesized using a Pt-decorated ZIF-67 sacrificial template, followed by a water-soaking treatment to enhance surface hydroxyl (─OH) group content. The as-designed N -Co 3 O 4 /Pt catalyst achieved a CO 2 conversion of 64% and CH 4 selectivity of 98% at 340 °C under ambient pressure. It was demonstrated that the interfacial N -stabilized Co 3+ -OH-Pt active sites in N -Co 3 O 4 /Pt improved synergy between cobalt and platinum, enhancing agglomeration resistance and enhancing catalytic performance. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) demonstrated that CO 2 is converted to methane mainly through a formic acid pathway, with no CO detected. This work underscores the critical role of surface hydroxyl groups in promoting CO 2 adsorption and activation, guiding the CO 2 methanation reaction toward efficient methane production.