Unraveling Tensile Strain Effect via W Single Atoms Onto MnO 2 for Enhanced Water Oxidation

ABSTRACT Designing efficient and stable oxygen evolution reaction (OER) electrocatalysts for anion exchange membrane water electrolysis (AEMWE) systems is critical for sustainable energy conversion. Here, we demonstrate a strain engineering strategy through hydrothermal impregnation to anchor W single atoms on MnO 2 nanofibers, effectively modulating their electronic structure. The introduced tensile strain weakens the metal‐oxygen bond strength, triggering a transition of the OER mechanism from the adsorbate evolution mechanism to the lattice oxygen‐mediated mechanism‐oxygen vacancy site mechanism (LOM‐OVSM). The optimized W 2.06% ‐MnO 2 exhibits superior OER performance with an overpotential of 230 mV at 10 mA cm −2 . When applied in an AEMWE cell, it requires 1.77 V to drive 1 A cm −2 and demonstrates continuous operation for over 450 h. This study provides fundamental insights into strain‐induced modulation of reaction pathways and offers a practical strategy for designing advanced electrocatalysts toward scalable green hydrogen production.