Descriptor Design in the Computational Screening of Ni-Based Catalysts with Balanced Activity and Stability for Dry Reforming of Methane Reaction

Dry reforming of methane (DRM) is an important reaction in the actual environmental and energy crisis context. It enables the production of syngas from CO2 and CH4 reforming. While Ni catalyst presents a high activity regarding this process, it often suffers from deactivation. It was found that the Sn-doped Ni catalyst can avoid carbon deposition, but a decrease in DRM reactivity was also observed. In this work, we used density functional theory calculations in combination with microkinetic modeling first to understand how Sn doping affects the resistance to carbon deposition and the surface catalytic activities of Ni. Based on the understandings, we found that an ideal dopant should give rise to a proper adsorption energy of carbon such that (i) the C* formation process, e.g., CH4 dissociation, is rate-controlling to improve the carbon resistance and (ii) relatively low dissociation barriers of CH4 and CO2 can be achieved to maintain a good activity. Therefore, the adsorption energy of carbon and the dissociation barriers of CH4 and CO2 can be utilized as descriptors for the stability and activity of Ni-based catalysts. Subsequently, we screened several metal dopants and found that the descriptors designed are capable of providing a consistent activity and stability trend with experiments reported in the literature. Therefore, our work could provide relevant guidelines to rationally design efficient catalysts for the DRM reaction.