Cooperative Fe-Ti dual-metal sites for highly efficient photocatalytic non-oxidative methane conversion

Selective methane conversion is a promising low-carbon technology, yet developing catalysts capable of effectively activating inert C-H bonds under mild conditions remains challenging. Here, we designed Fe²⁺-□-Ti⁴⁺ dual-metal-sites on the high-activity {012} facets of defective ilmenite (Fe_1-x TiO_3-x -NS). Mechanistic studies revealed that Fe²⁺-□-Ti⁴⁺ can be excited to form a long-lived Fe³⁺-□-Ti³⁺ active state, while surface lattice oxygen stabilizes the reaction intermediates during multistep elementary reactions. This bimetal-oxygen synergistic strategy significantly reduces the activation barrier for C-H bond cleavage to just 0.15 eV, fully blocks the over-dehydrogenation of methyl intermediates, and facilitates C-C bond formation, thereby achieving a favorable non-oxidative methane conversion rate that even surpasses noble metal-supported photocatalysts, with nearly 100% C₂₊ selectivity. This bimetallic-center construction strategy not only provides an efficient and economical pathway for methane conversion but also expands the boundaries of traditional photocatalysts, exhibiting high catalytic activity and product selectivity.