On the structures, electronic properties, and hydrogen dissociation of the noble-metal-free molybdenum carbide clusters

Seeking efficient non-noble metal cluster catalysts is of significant importance. Herein, we theoretically report a systematic investigation into the geometry and electronic properties of the (MoC)_n clusters (n = 1–4). The symmetric (MoC)₄ cluster exhibits high electron-donating capacity and spin crossover during H₂ dissociation, mirroring Pd₄'s pathway and positioning it as a cost-effective Pd₄ alternative. Furthermore, the cubic-honeycomb (MoC)₄ cluster solid was observed to exhibit high thermal stability up to 800 K and metallic characteristics dominated by Mo-4d orbitals. This study provides new insights in designing noble-metal-free cluster catalysts for sustainable H₂ activation and nanoscale applications.