Water oxidation electrocatalyzed by an efficient Mn3O4/CoSe2 nanocomposite.

ABSTRACT

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.