Yao, Xiaoyu; Meng, Xuan; Liu, Naiwang; Liu, Yuxin; Li, Ruitao; Lim, Kang Hui; Shi, Li; Kawi, Sibudjing; Zhong, Liangshu

CHEMICAL ENGINEERING JOURNAL

2025, ,

Yao, Xiaoyu; Meng, Xuan; Liu, Naiwang; Liu, Yuxin; Li, Ruitao; Lim, Kang Hui; Shi, Li; Kawi, Sibudjing; Zhong, Liangshu

Designing cost-effective, high-performance non-noble metal catalysts for low-temperature CO2 activation attract great attention but remains formidable challenge. Herein, we report a deep eutectic solvent (DES)-assisted alkaline treatment strategy to precisely engineer high-density Ni-Ov-Ce interfacial sites on Ni/CeO2-DA catalysts, concurrently introducing hydroxyl-mediated basic sites and achieving ultrafine, highly dispersed Ni nano-particles. The resultant synergistic multi-active site architecture boost CO2 methanation at low temperatures, delivering exceptional methane selectivity (99.8 %) and CO2 conversion (86.5 %) at 250 degrees C, approaching the equilibrium conversion while maintaining long-term stability. Structural and spectroscopic characterizations reveal strong electronic interaction between Ni nanoparticles and the oxygen vacancy-enriched CeO2 support, which facilitates intermediate hydrogenation and CO2 methanation. In situ DRIFTS identifies hydroxyl-decorated surfaces that stabilize *HCOO-intermediates, favoring the formate-mediated pathway as the dominant mechanism. This work provides a facile yet effective strategy for constructing robust metal-oxide interface catalysts.