Potential of nickel nanoclusters supported on alpha-Al2O3(0001) surface for CO2 capture, energy production, and dry reforming of methane

The structural, electronic and magnetic properties of Ni-n@alpha-Al2O3(0001) (with n = 1 to 7) systems have been studied using density functional theory. Grafting energies, Bader charges and DOS analysis showed that the nickel clusters strongly interact with the alpha-Al2O3(0001) surface. In a second step, the adsorption performances of these materials towards CH4, CO2, CO, H-2 gases have been evaluated. Pure alumina surface and supported Ni systems weakly interact with methane, which are therefore promising for an efficient purification of methane. Additionally, it was found that the pure alumina surface and Ni-5/alpha-Al2O3(0001) selectively adsorb the CO2, facilitating its storage and utilization. A selective adsorption was also observed for CO on Ni-3/alpha-Al2O3(0001). Looking now at the dry reforming of methane, a strong adsorption of CO was shown in all supported systems. The dissociative adsorption of hydrogen on all supported systems (except for n = 4) was observed. A high resistance against carbon deposition was observed on our modeled systems compared to those reported in the literature, which is a promising result since the rapid deactivation by coke deposition is the main problem for the catalysts used in the dry reforming of methane process.