Exploring CO₂ Methanation Using 3D-Printed Carbon Architectures

To demonstrate for the first time the potential of stereolithography-printed, architected, bio-based carbon-supported Ni catalysts for CO₂ methanation, three honeycomb carbon structures with different textural properties were prepared, impregnated with 15 wt.% of nickel metal particles, and studied to correlate their catalytic performances with their textural properties and surface chemistry. Compared with the non-activated monolith and the steam-activated monolith, the CO₂-activated monolith achieved a higher CO₂ conversion of 62 % with a CH₄ selectivity of 73 % at 460 °C. Our comparative study demonstrated that the CO₂-activated carbon support, although having fewer basic sites on the surface, exhibits greater dispersion of the Ni phase, enabling an increase in H₂ chemisorption. These results are of interest for further studies related to the optimization of catalytic performance through the design of the architectural and textural properties of such macrostructures.