Strategic integration of yttrium single atoms on CeO2 supported nickel catalysts for enhanced CO2 methanation catalysis

We report the synthesis of a high-performance CO 2 methanation catalyst, Ni-Y 1 /CeO 2 , comprising Ni nanoparticles and atomically dispersed Y 3 + on a ceria support. This precisely designed catalyst achieved an outstanding CO 2 conversion of 83 % with 100 % CH 4 selectivity at 350 °C. XAS unambiguously confirmed the atomic dispersion of Y 3+ with the absence of any Y-Y bonds, while STEM-EDS revealed uniform Y distribution with finely dispersed Ni NPs. Enhanced oxygen vacancies and improved basic sites contributed to the superior activity of Ni-Y 1 /CeO 2 even at low temperature (250–300 °C) and showed excellent stability over 40 h. Comparative studies with impregnated NiY/CeO 2 -imp and Ni/CeO 2 highlighted the synergistic effect of Y 3+ and Ni. These results establish Y 3+ single-atom modulation as a powerful approach to tailoring basic sites and enhanced oxygen vacancies, unlocking new design pathways for advanced CO 2 methanation catalysts. Herein, Ni-Y 1 /CeO 2 catalyst with atomically dispersed Y 3+ as isolated atoms and Ni nanoparticles achieved superior CO 2 conversion and excellent CH 4 selectivity even at lower temperatures. Advanced characterizations confirmed isolated Y 3+ atoms, enhanced oxygen vacancies, and enhanced basic sites. This promoter-metal configuration leverages the atomic-level incorporation of Y 3+ to modulate Ni/CeO 2 interactions for enhanced catalytic performance. • Design and synthesized Y 3+ single atom along with NiO nanoparticles over CeO 2 support. • Ni-Y 1 /CeO 2 SACs showed excellent catalytic performance for CO 2 to CH 4 conversion. • STEM-EDS confirmed the uniform dispersion of Y 3+ on CeO 2 support with NiO. • XPS and XAS confirmed the Y 3+ doping enhancement in oxygen vacancies. • Comparative study confirmed superior performance of SAC over undoped and impregnated catalysts.