Nanostructured CeO2 as support of Ni-catalysts for plasma-catalytic CO2 methanation: Tailoring support’s nanomorphology towards improved performance

Abstract

Plasma-assisted CO2 methanation has been recently presented as a highly promising route towards the electrification of power-to-gas processes, a key step in our transition to sustainable energy generation. Interesting results have been obtained via the combination of cold plasmas – such as Dielectric Barrier Discharge – and Ni-catalysts prepared using CeO2-containing oxides as support, well known for they ability towards oxygen exchange. In the present work, the physicochemical and dielectric properties of Ni/CeO2 catalysts were tailored through the modification of the nanostructured morphology of pure CeO2, as an alternative to the use of dopants/promoters. Improved efficiency was observed in the presence of CeO2 nanoneedles and nanorods exposing 〈011〉 facets, more prompt to oxygen exchange. The lower dielectric permittivity of these materials led to a more efficient management of adsorbed species during on-plasma operation, resulting in improved plasma-catalytic behavior.