Photoassisted Dry Reforming of Methane Mediated by a Non-noble Molybdenum–Cobalt Oxide Cation Mo ₂ CoO ₂ ⁺

Dry reforming of methane (DRM) converts CH₄ and CO₂ to syngas but suffers from high endothermicity and catalyst coking. Developing efficient, non-noble metal catalysts demands atomic-level insights. Here, we combine mass spectrometry and theoretical calculations to investigate the structure and catalytic performance of the bimetallic oxide cluster Mo₂CoO₂⁺ in DRM. Mass spectrometry data confirm a complete catalytic cycle, which proceeds through the sequential cleavage of the four C-H bonds in CH₄ followed by CO₂ activation. The first three C-H bond activations occur in the dark, while the fourth C-H bond activation and subsequent C-O coupling are photoinduced. Density functional theory (DFT) calculations reveal a dynamic synergistic mechanism. The Mo and Co atoms mediate electron transfer for C-H activation via the formation of metal-carbon bonds. Meanwhile, the oxygen ligands are critical for maintaining structural stability and suppressing carbon deposition. Our findings reveal a synergistic, photoenhanced DRM mechanism and establish Mo-Co oxide clusters as a promising, coke-resistant catalyst design.