CO2 methanation using nickel-based catalysts has attracted large interest as a promising power-to-gas route.Ni nanoparticles supported on nitrogen-doped CNTs with Ni loadings in the range from 10 wt％to 50 wt％were synthesized by impregnation,calcination and reduction and characterized by elemental analysis,X-ray powder diffraction,H2 temperature-programmed reduction,CO pulse chemisorption and transmission electron microscopy.The Ni/NCNT catalysts were highly active in CO2 methanation at atmo-spheric pressure,reaching over 50％CO2 conversion and over 95％CH4 selectivity at 340 ℃ and a GHSV of 50,000 mL g-1 h-1 under kinetically controlled conditions.The small Ni particle sizes below 10 nm despite the high Ni loading is ascribed to the efficient anchoring on the N-doped CNTs.The optimum loading of 30 wt％-40 wt％Ni was found to result in the highest Ni surface area,the highest degree of con-version and the highest selectivity to methane.A constant TOF of 0.3 s-1 was obtained indicating similar catalytic properties of the Ni nanoparticles in the range from 10 wt％to 50wt％Ni loading.Long-term experiments showed that the Ni/NCNT catalyst with 30 wt％Ni was highly stable for 100 h time on stream.