摘要
Surface and interface engineering play a crucial role in enhancing the CO2 methanation performance of heterogeneous catalysts. In this study, we present NiO-TiO2 nanoparticles modified with oxygen vacancy-rich Fe3O4 clusters, significantly improving CO2 methanation performance. The as-prepared catalyst (referred to as NiO@Fe3O4) achieves an impressive CH4 selectivity of 91.2% and a methane production yield of 6400.50 mu mol/g at 573 K, an approximately 83% increase compared to unmodified NiO nanoparticles (3154.2 mu mol/g). The results of physical characterizations and gas chromatography confirm that the outstanding activity and selectivity of the NiO@Fe3O4 catalyst arise from the synergistic interaction between its surface-active sites. Notably, the high concentration of oxygen vacancies within Fe3O4 enhances CO2 activation, while adjacent NiO sites efficiently promote H-2 dissociation. These findings provide valuable insights into the rational design of heterogeneous catalysts, highlighting the advantages of Fe3O4 as an efficient promoter over conventional metal oxides for catalytic applications. Additionally, we envision that the obtained results will help to design transition metal-based industry viable catalysts for a diverse range of applications.