Dense heterogeneous interfaces boost the electrocatalytic oxygen evolution reaction

Efficient and cost-effective catalysts are essential to drive the oxygen evolution reaction (OER) in sustainable hydrogen production through water splitting. In this study, we introduce an innovative strategy aimed at constructing heterogeneous structure that form abundant Fe2O3/NiSe2 interfaces on the FeOOH surface. The resulting catalyst exhibits extraordinary performance with an excellently low overpotential of 169 mV at 10 mA cm−2. Notably, this catalyst also demonstrates impressive long-term stability in alkaline seawater. Compared to traditional heterogeneous catalysts with core-shell structures, Fe2O3/NiSe2 possesses a closely heterogeneous interface, which plays a role in modulating the interface electron. Supported by complementary spectroscopy and theoretical calculations, it has been further demonstrated that the distinctive Fe-O-Ni-Se structure can effectively modulate the electronic state of Ni, thereby enhancing the adsorption of oxygen-containing intermediates and facilitating oxygen desorption. Overall, this research presents a promising avenue for enhancing the electrocatalytic performance by amplifying active sites at interfaces.