Synergistic flower-like N-doped Co/Mo2C catalyst for hydrogen evolution reaction in universal pH and high-performance alkaline water-splitting

Developing highly efficient and stable non-precious metal catalysts for water splitting is crucial for advancing sustainable energy technologies. This study introduced a pioneering step-temperature synthesis of a selfsupporting N-doped Co/Mo2C catalyst with a unique flower-like morphology, termed N-Co/MCNF750. The innovative morphology is achieved through a synergistic process involving the thermal decomposition of trimesic acid (TMA), controlled three-step temperature modulation, N-doping, and interactions between the carbon matrix and metal nanoparticles. It resulted in a high surface area, abundant active sites, and defect-rich structure, essential for catalytic efficiency. N-doping enhanced electrical conductivity, surface wettability, and interaction with water-oxidation intermediates, which contributed to the N-Co/MCNF750 catalyst exhibiting outstanding HER activity with low overpotentials of 72, 120, and 83 mV at 10 mA cm- 2 in alkaline, acidic, and neutral media, respectively, along with exceptional durability over 100-h. For the OER in alkaline media, the catalyst showed a low overpotential of 198 mV at 10 mA cm- 2 and long-term stability for 100-h. Additionally, the catalyst achieved an OWS voltage of 1.54 V at 10 mA cm-2 in 1.0 M KOH, demonstrating excellent stability over 300-h. These findings underscored the novel methodology for designing electrode materials using transition metals, advancing the development of efficient, robust, and universal pH catalysts for HER and overall alkaline water splitting.