Interfacial Co─N Coordination Engineering in Bimetallic Carbide Nanocluster-Embedded Chainmail Catalysts Boosts Water...

Developing efficient and stable oxygen evolution reaction (OER) catalysts is critical for renewable energy applications. Guided by theoretical calculations, this work develops a rational interfacial design in OER chainmail catalysts composed of bimetallic carbide nanoclusters embedded within nitrogen-doped carbon nanotubes (CoMoC-NCNTs), derived from a CoMo-MOF precursor. Utilizing X-ray absorption fine structure spectroscopy and in situ characterization, the synthesized CoMoC-NCNTs chainmail catalyst exhibits precisely tunable interfacial Co─N coordination regulated by pyrolysis temperature and abundant active carbon sites on a highly conductive network for OER via the adsorbate evolution mechanism. Density functional theory (DFT) calculations reveal that the introduction of interfacial Co─N coordination in CoMoC nanocluster-embedded chainmail catalysts triggers electron transfer from inner CoMoC nanoclusters to outer carbon layers, which further optimizes OER intermediate adsorption on carbon sites with a lower energy barrier for the rate-determining step (0.44 eV). Consequently, the optimal CoMoC-NCNTs chainmail catalyst for alkaline OER exhibits exceptional catalytic activity (overpotential of 297 mV at 10 mA cm^-2) and excellent durability (500 mA cm^-2 for 200 h). The constructed volcanic plot further establishes structure-activity relationships for guiding future designs of chainmail catalysts. This work provides a universal strategy for engineering nanocluster-embedded chainmail catalysts with tailored electronic structures for advanced electrocatalysis.