Maximizing hydrogen evolution via Co–Ni dual atoms and nanoclusters on hierarchically ordered porous carbon framework

Efficient hydrogen production through water splitting relies on the development of high-performance catalysts for the hydrogen evolution reaction (HER). In this study, we synthesized the CoNi SAs@NPs-NC catalyst using multi-metal single-crystal ordered macroporous metal-organic frameworks (MOFs) as precursors. This catalyst features a hierarchical porous structure with ordered macropores and micropores, which not only provides a high specific surface area but also promotes efficient mass diffusion. Furthermore, the incorporation of bimetallic components, coupled with synergistic interactions between single atoms (SAs) and nanoparticles (NPs), significantly enhances its catalytic activity. The CoNi SAs@NPs-NC nanocatalysts demonstrated exceptional activity in the HER, recording overpotentials of 90 mV in 1 M KOH and 61 mV in 0.5 M H₂SO₄, both at a current density of 10 mA cm⁻². In addition, density functional theory (DFT) analysis was employed to investigate the synergistic interactions among CoNi NPs, SAs, and nitrogen dopants. Our finding highlights the promising potential of the CoNi SAs@NPs-NC catalyst for efficient hydrogen evolution, making it a valuable candidate for advancing the field of water splitting.