Graphene Quantum Dot‐Induced Microstrain for Framework Stabilization of High‐Entropy Prussian Blue Analog in High‐Current Alkaline Hydrogen Evolution Reaction

Rising demand for green hydrogen is accelerating interest in electrocatalytic water splitting, but durable, earth‐abundant catalysts that operate at industrial current densities remain scarce. Prussian blue analog (PBA) are attractive hydrogen evolution reaction (HER) catalysts due to their compositional versatility and environmental sustainability, yet their actual performance is limited by insufficient availability. Here, we show that graphene quantum dots (GQD) encode a built‐in, localized lattice distortion into high‐entropy PBA (HEPBA), transforming microstrain into an operando stabilizing function. While XRD and XAS demonstrate that GQD coupling induces localized lattice contraction and coordination‐confined bond distortion, the in situ XAS and in situ Raman further reveal that this pre‐built microstrain “locks” the Co─C≡N bridge, suppressing electrolyte‐induced coordination disorder under HER. By preserving local order across the cyanide network, thereby sustaining framework‐mediated charge transport and enabling durability. DFT calculations further show that the strained HEPBA/GQD model promotes more favorable H 2 O adsorption and regulated H* adsorption energetics. As a result, HEPBA/GQD reach 207 mV at 100 mA cm − 2 in 1.0 M KOH, and maintain stable operation at 500 mA cm − 2 for 72 h, whereas pristine HEPBA significantly lose their initial current, highlighting microstrain‐enabled stabilization as a general pathway to robust coordination electrocatalysts.