The incorporation of rare earth metals into transition metal-based catalysts markedly improves their adsorption properties toward intermediates during coupled glycerol electro-oxidation and hydrogen evolution reactions. However, direct f-d electron hybridization often induces Fermi surface instability, limiting catalytic durability. To address this, we propose a novel strategy involving Dy and S co-doped NiMoO 4, where 4f-2p-3d gradient orbital coupling is introduced alongside sulfur vacancies (Sv) via Ar plasma etching. This approach simultaneously reduces the catalyst’s work function and mitigates interfacial charge accumulation, yielding bouquet-like Dy-doped NiMoO 4 with abundant Sv (Sv/Dy-NiMoO 4/NF). The optimized catalyst demonstrates remarkable performance in glycerol electrooxidation-coupled hydrogen production, achieving an exceptionally low hydrogen evolution overpotential of 29 mV at 10 mA cm -2 while simultaneously maintaining a cell voltage of just 1.39 V in membrane electrode assembly operation. This configuration provides a 260 mV reduction in potential compared to conventional overall water splitting, while additionally enabling the co-production of high-value formate as oxidation products. Experimental and theoretical analyses reveal that Sv optimize the electronic microenvironment, strengthening the adsorption of OH* and glycerol* intermediates. This work not only advances the design of high-efficiency electrocatalysts for energy-saving hydrogen production but also provides a sustainable route for co-producing valuable chemicals.