Highly Efficient and Selective Light-Driven Dry Reforming of Methane by a Carbon Exchange Mechanism.

Dry reforming of methane (DRM) is a promising technique for converting greenhouse gases (namely, CH 4 and CO 2 ) into syngas. However, traditional thermocatalytic processes require high temperatures and suffer from low selectivity and coke-induced instability. Here, we report high-entropy alloys loaded on SrTiO 3 as highly efficient and coke-resistant catalysts for light-driven DRM without a secondary source of heating. This process involves carbon exchange between reactants (i.e., CO 2 and CH 4 ) and oxygen exchange between CO 2 and the lattice oxygen of supports, during which CO and H 2 are gradually produced and released. Such a mechanism deeply suppresses the undesired side reactions such as reverse water-gas shift reaction and methane deep dissociation. Impressively, the optimized CoNiRuRhPd/SrTiO 3 catalyst achieves ultrahigh activity (15.6/16.0 mol g metal -1 h -1 for H 2 /CO production), long-term stability (∼150 h), and remarkable selectivity (∼0.96). This work opens a new avenue for future energy-efficient industrial applications.