The rational design of electrocatalysts with dual active centers is pivotal for achieving high activity and stability in the oxygen evolution reaction (OER). In this study, a novel CoOx@Co-NC catalyst was developed through a ligand-mediated thermal polymerization strategy, where cobalt species are simultaneously anchored as both Co-N₄ macrocycles and ultrafine CoOx nanoclusters within a nitrogen-doped carbon matrix. The synthesis begins with the copolymerization of urea and oxalic acid to form oxygen-doped carbon nitride (OCN), followed by incorporation of cobalt ions via coordination with oxalate ligands. This results in a well-defined Co-OCN precursor with atomic-level dispersion of cobalt. Upon carbonization at 700 °C under inert atmosphere, the ligand framework decomposes into a conductive NC matrix while preserving the spatial distribution of cobalt species. The liberated oxygen from the ligand reacts with uncoordinated cobalt atoms, forming highly dispersed CoOx nanoclusters strongly bonded to the carbon substrate. The resulting CoOx@Co-NC exhibits exceptional OER performance, with an onset potential at 353 mV and a Tafel slope of 40 mV/dec—outperforming benchmark RuO₂. The synergy between the two active centers is critical: Co-N₄ sites serve as primary catalytic hubs, lowering the activation energy for OER steps, while surface CoOx nanoclusters enhance OH⁻ adsorption and facilitate proton-coupled electron transfer at the electrode-electrolyte interface. XPS analysis confirms the coexistence of Co²⁺, Co³⁺, and Co-N₄ bonding configurations, indicating redox-active cobalt species essential for catalysis.IL1F9 Antibody Biological Activity HAADF-STEM imaging reveals atomic-scale dispersion of cobalt clusters, with no evidence of large aggregates even at high loadings (~20 wt.59-05-2 web %).PMID:35217283 Electrochemical impedance spectroscopy shows significantly reduced charge transfer resistance compared to RuO₂, while double-layer capacitance measurements confirm a high electrochemically active surface area. Long-term durability tests demonstrate negligible degradation after 1000 CV cycles and 10 hours of constant current operation. These results highlight that the dual-active-center architecture not only maximizes atomic utilization but also enables robust interfacial kinetics. This work provides a scalable and versatile approach to engineering advanced electrocatalysts, offering a promising pathway toward efficient and cost-effective water splitting technologies.
This article is protected by copyright. All rights reserved.MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com