Facilely fabricating highly dispersed Ni-based catalysts supported on mesoporous MFI nanosponge for CO2 methanation

The Ni-based catalysts were widely investigated as the catalysts toward CO2 methanation reaction because of their availabilities. However, compared with the noble metal based catalysts, the design and exploitation of Ni-based catalysts with outstanding low-temperature catalytic activities is still a big challenge. In order to solve this problem, the highly dispersed Ni catalysts had been facilely prepared by employing the basic amine functionalized mesoporous MFI nanosponge zeolite as the support. The functionalized amine group could induce the precisely regioselective precipitation of the Ni precursor in the mesoporous channels and the highly dispersed Ni nanoparticles were obtained. Besides, the La2O3 and MgO had been used to modify the surface basicity to further promote the low-temperature catalytic activities of the Ni-based catalysts. These catalysts were systematically measured by XRD, N-2 physisorption, STEM, XPS, H-2-TPR, and CO2-TPD. It was observed that the metallic Ni nanoparticles were homogenously distributed among the mesoporous channels. Furthermore, the La2O3 and MgO modification could obviously promote the surface basicity of the catalysts, which intensified the CO2 adsorption and activation. Thus, their apparent activation energies of CO2 methanation evidently decreased and their low-temperature activities were greatly promoted. Besides, it was also found that the thermal agglomeration of the Ni nanoparticles could be successfully inhibited via the confinement effect of the amine functionalized mesoporous channels, interpreting their excellent catalytic stabilities toward CO2 methanation.