Dynamic-Adaptive hydrogen evolution enabled by synergistic electronic-structure engineering in biomass-derived NiCo–Mo2C@BC heterostructures

Cost-effective, high-performance electrocatalysts for sustainable water splitting is critical for advancing renewable energy utilization and facilitating large-scale green hydrogen production. Molybdenum carbide (Mo 2 C) has emerged as a promising alternative to platinum-based catalysts due to its comparable electronic properties. However, its practical application has been impeded by inefficient synthesis methods and inadequate catalytic activity. To address these limitations, This work presents a straightforward one-step hydrothermal-carbonization to engineer a nickel-cobalt-molybdenum carbide composite anchored on cotton stalk-derived carbon (NiCo–Mo 2 C@BC). Systematic analyses reveal that dual electronic between bimetallic NiCo dopants and Mo 2 C phases, coupled with the defect-rich carbon architecture derived from cotton stalks, collaboratively optimizes charge transport kinetics and exposes abundant active sites. The integrated carbon framework further confers exceptional mechanical resilience against prolonged electrochemical stress. The catalyst achieves favorable HER performance in 1.0 mol L −1 KOH, requiring overpotentials of just 166 mV and 258 mV to drive current densities of 10 mA cm −2 and 50 mA cm −2 respectively. Furthermore, the system demonstrates remarkable durability over 100 h and exhibits resilience against fluctuating currents. This work not only elucidates the crucial role of cooperative effects among transition metals in regulating the electrocatalytic performance of carbides, but also highlights the potential for converting agricultural waste into high-value electrocatalytic materials through environmentally sustainable methods.