An in situ defect engineering approach for light-driven methane dry reforming over atomically distributed nickel

Abstract

Dry reforming of methane economically converts methane and carbon dioxide into syngas (hydrogen and carbon monoxide) but requires high energy and often suffers from catalyst instability. Here, a surface-modulation strategy is demonstrated via decorating in situ defects on isolated nickel (Ni) atoms over La2O3 for boosting light-driven dry reforming of methane activity. Atomically dispersed 0.5Ni/La2O3 achieves a hydrogen evolution rate of 170.9 mol gNi−1 h−1. The reactivity is mainly attributed to photogenerated electrons, which overcome the limitations of a purely thermal system. The in situ generation of oxygen vacancies increases the initial-stage reactivity, where oxygen vacancies act as electron traps to accelerate charge separation and promote the adsorption/activation of reactants. The 0.5Ni/La2O3 catalyst exhibits strong inhibition of carbon coking and is sintering resistant, benefiting from the synergy between in situ oxygen vacancies and isolated nickel atoms.