Electrified dry reforming of methane on Ni-La₂O₃-loaded activated carbon: A net CO₂-negative reaction

Dry reforming of methane (DRM) offers an attractive solution for the high-value utilization of two primary greenhouse gasses, methane and carbon dioxide, but its industrial applications are hindered by the net carbon dioxide-positive emissions resulting from substantial energy consumption. Here, we developed an electrified technology by passing electric current through a conductive catalyst constituting nickel and lanthanum(III) oxide cosupported on activated carbons, reaching thermodynamic equilibrium conversions and sustaining for at least 120 hours. Notably, the energy efficiency (2.976 millimoles per kilojoule) exceeds all the previously reported values, enabling net carbon dioxide-negative emissions powered by common sustainable electricity. An electrically driven release of lattice oxygen bridges the decomposition of the lanthanum oxycarbonate intermediate generated from carbon dioxide activation and the reduction of the resultant nickel oxide species by deposited carbon from methane dissociation, thus inhibiting excessive nickel oxidation and lanthanum(III) oxide carbonatation. The electrified approach would make DRM a true pathway mitigating overall carbon footprint and combating global warming.