Effect of t-ZrO2/m-ZrO2 Phase Interfaces on the Stability of Ni/Ca-ZrO2 Catalysts for CO2 Methanation

The m/t-ZrO2 interphase boundaries provided anchoring sites for Ni nanoparticles, which is identified as the primary reason for the superior high-temperature anti-sintering performance of the catalyst calcined at 700 °C. In addition, these mixed-phase interfaces optimized the local electronic structure and enriched oxygen vacancy defects, thereby lowering the apparent activation energy for CO2 activation and endowing the 700 °C calcined catalyst with the highest low-temperature CO2 methanation activity.

These findings demonstrate that constructing m/t-ZrO2 interphase boundaries through promoter engineering and thermal-treatment control is an effective strategy to stabilize Ni nanoparticles and enhance catalytic performance.