Three-dimensional open CoMoOx/CoMoSx/CoSx nanobox electrocatalysts for efficient oxygen evolution reaction

Electrocatalytic oxygen evolution reaction (OER) based on geometric structure and interfacial-site engineering of catalysts is an excellent strategy for the hydrogen production by water electrolysis. Herein, a novel class of three-dimensional (3D) CoMoOx/CoMoSx/CoSx (CoMoOS) nanoboxes (NBs) electrocatalysts with abundant interfaces is designed through a facile dissolution-regrowth and ion-exchange process employing ZIF-67 as the sacrificial template. Remarkably, the rich interfaces not only endow the CoMoOS with a high surface active area but also provide a "highway" for charge transport, thereby optimizing the binding strength of reaction intermediates on CoMoOS and drastically boosting the oxygen production. More interestingly, the unique nanobox structure also endows the catalyst with a 3D accessibility for reactants. As a result, the 3D CoMoOS NBs achieve not only an ultralow overpotential of 281 mV at 10 mA cm(-2), but also high-performance overall water electrolysis at alkaline media, with a cell potential of 1.58 V at 10 mA cm(-2).