Thermal-stimulated spin disordering accelerates water electrolysis

The sluggish kinetics of the oxygen evolution reaction (OER) greatly limits the efficiency of water splitting. The high OER overpotentials would originate from the high electron transfer barriers in the electrolyte/catalytic layer/catalyst core interfaces during the water oxidation reactions. Here, we assemble the temperature-dependent magnetic YFe1-xMnxO3 core and the paramagnetic YFeOOH shell to form a YFe1-xMnxO3@YFeOOH core-shell structured catalyst to explore the effects of thermal-stimulated magnetic state of catalytic materials on OER kinetics. We find that the thermal-stimulated paramagnetic state of YFe1-xMnxO3 core contributes to the accelerated electron transfer at the YFe1-xMnxO3@YFeOOH core-catalytic layer interface. Meanwhile, it improves the intrinsic OER activities of the YFeOOH catalytic layer. The thermal-stimulated magnetic transition of YFe1-xMnxO3 (from antiferromagnetic to paramagnetic) enlarges the magnetic disorder at the YFe1-xMnxO3@YFeOOH interface to reduce the spin flipping barriers and induces to produce the highly OER-active electronic states for YFeOOH catalytic layer due to the strong interactions between YFe1-xMnxO3 core and YFeOOH catalytic layer, thus breaking the linear Arrhenius relationship. Our findings provide a new low-barrier OER route by thermal-stimulated magnetic disordering.