Ru-Loaded Mo@PDA Nanoflower-Derived Ru@MoC/N-CFSs as Electrocatalysts for the Hydrogen Evolution Reaction

The development of highly efficient and stable non-precious metal-based electrocatalysts for the hydrogen evolution reaction (HER) is pivotal for advancing sustainable hydrogen production via water splitting, which is considered a cornerstone technology for future clean energy systems. In this work, we report the rational design, controlled synthesis, and comprehensive characterization of ruthenium-doped molybdenum carbide-loaded nitrogen-doped carbon flower spheres (Ru@MoC/N-CFSs-T, where T denotes the pyrolysis temperature), employing Mo@polydopamine (Mo@PDA) as versatile precursors. The synthesized nanostructures feature a unique hierarchical nanoflower morphology, which significantly increases the exposure of active sites, facilitates rapid electron and mass transfer, and enhances electrolyte accessibility. The synergistic interaction between Ru and MoC not only modulates the electronic structure of the active sites but also optimizes the adsorption/desorption behavior of hydrogen intermediates, thereby boosting the intrinsic catalytic activity. Electrochemical evaluations reveal that the optimized Ru@MoC/N-CFSs-800 catalyst demonstrates remarkable HER performance in alkaline media, characterized by a low overpotential, a small Tafel slope, and excellent long-term durability over extended cycling. This study highlights the importance of precise compositional tuning and structural engineering in designing high-performance HER electrocatalysts and provides a promising strategy for developing cost-effective, non-precious metal-based catalysts for large-scale hydrogen production.