Water oxidation electrocatalyzed by an efficient Mn3O4/CoSe2 nanocomposite.

The design of efficient, cheap, and abundant oxygen evolution reaction (OER) catalysts is crucial to the development of sustainable energy sources for powering fuel cells. We describe here a novel Mn(3)O(4)/CoSe(2) hybrid which could be a promising candidate for such electrocatalysts. Possibly due to the synergetic chemical coupling effects between Mn(3)O(4) and CoSe(2), the constructed hybrid displayed superior OER catalytic performance relative to its parent CoSe(2)/DETA nanobelts. Notably, such earth-abundant cobalt (Co)-based catalyst afforded a current density of 10 mA cm(-2) at a small overpotential of ~0.45 V and a small Tafel slope down to 49 mV/decade, comparable to the best performance of the well-investigated cobalt oxides. Moreover, this Mn(3)O(4)/CoSe(2) hybrid shows good stability in 0.1 M KOH electrolyte, which is highly required to a promising OER electrocatalyst.