Bioinspired tandem catalyst with topological ordered water networks accelerates alkaline hydrogen evolution electrocatalysis

The sluggish kinetics of alkaline water dissociation and its competitive interference with hydrogen evolution steps, driven by inefficient interfacial water-catalyst interactions, challenge the efficiency of the hydrogen evolution reaction (HER). Inspired by H+ /K+ -ATPase-like specific water orientations that enhance proton transport, we report a Co-NiMo tandem catalyst for decoupling water dissociation and hydrogen evolution through electronegativity-driven H-Co/O-NiMo interfacial water alignment, achieving spatial separation of active sites. Density functional theory (DFT) calculations screening across five descriptors identifies Co as the optimal partner for NiMo, enabling efficient spatial separation of active sites. The optimized Co-NiMo tandem catalyst achieves exceptional performance with a low HER overpotential of 27 mV at 10 mA cm⁻² and maintains > 1-week stability at 500 mA cm⁻² in anion exchange membrane water electrolyzer (AEMWE), exceeding most state-of-the-art Ni-based catalysts ever reported. In-situ spectroscopy combined with ab initio molecular dynamics (AIMD) simulations reveals an oriented H-Co/O-NiMo water configuration, weakening H-O bonds and accelerating HER kinetics. This work not only establishes a new paradigm for electrocatalyst design, but also advances sustainable energy conversion technologies.