摘要
Developing efficient and low-temperature CO
methanation catalysts is essential for advancing green energy technologies. Herein, we report a highly active catalyst system comprising oxygen vacancies enriched atomic cobalt-oxide clusters anchored on the oxygen-deficient TiO
-supported NiO nanoparticles (denoted as NiCo- TiO
). The as-developed NiCo-TiO
catalyst initiates CH
production at a low temperature of 200 ◦C and delivers the highest methane production yield of ~6516 μmol g
at 300 ◦C. This performance surpasses that of Ni-TiO
(4657 μmol g
) and a physical mixture of Ni+Co-TiO
(3580 μmol g
) by ~29 % and 45 %, respectively. In situ X-ray absorption spectroscopy reveals that this enhanced activity originates from synergistic interactions between oxygen vacancies in the TiO
lattice, NiO nanoparticles, and the surface-decorated Co-oxide clusters. Specifically, Ni atoms partially replace Ti in the TiO
lattice, generating abundant oxygen vacancies that facilitate CO
activation, while NiO nanoparticles favor H
splitting. The surface cobalt-oxide clusters further boost CO
activation due to oxygen deficiency and serve as electron-rich sites, enabled by charge relocation from both Ti and Ni domains to Co sites. This study demonstrates a simple and effective strategy to design high-performance CO
methanation catalysts through defect engineering and selective cluster decoration.