Synergistic regulation of defect and basic sites in Ni–ZrO2 catalysts for dry reforming of methane

Nickel-based catalysts show promise for the dry reforming of methane (DRM); however, their application is often limited by carbon deposition and metal sintering. In this study, Ni–ZrO 2 catalysts featuring abundant defect sites and medium-strength basic sites were rationally designed to enhance catalytic performance. Defect sites facilitate the lattice incorporation of Ni into the ZrO 2 framework, thereby strengthening metal-support interactions, suppressing Ni aggregation, and enhancing CH 4 activation. Concurrently, coordinatively unsaturated O 2− species along with Zr 4+ -O 2- acid-base pairs provide medium-strength basic sites that improve CO 2 adsorption and activation, promoting carbon removal. The synergistic interaction between defect sites and basic sites enhances catalytic activity, stability, and the regulation of the H 2 /CO ratio. At 700 °C, the optimized catalyst achieves CH 4 and CO 2 conversions of 83.41% and 77.24%, respectively, maintaining an H 2 /CO ratio of 1.3 with excellent resistance to coke formation. These findings confirm that regulating defect sites and surface basicity is an effective strategy for developing high-performance DRM catalysts. • Proposing a Synergistic Mechanism Between Medium-Strength Basic Sites and Oxygen Vacancy Defects. • Electron Transfer Regulation Mechanism Induced by Lattice Doping. • Medium-strength basic sites make a significant contribution to CO 2 activation over the catalysts. • Exhibiting excellent activity and stability at 700 °C, with no detectable deactivation over 12 h of operation.