Porous amorphous FeCo alloys as pre-catalysts for promoting the oxygen evolution reaction

The design and development of efficient electrocatalysts composed of earth-abundant elements for oxygen evolution have gained significant attention. In this study, a FeCo alloy electrocatalyst with an amorphous and porous structure was designed and prepared. The electrochemical test results showed that the amorphous alloy product with a Co:Fe molar ratio of 2:1 showed an optimal intrinsic catalytic activity for oxygen evolution. At a current density of 10 mA cm(2), only a small overpotential of 290 mV was required in a KOH solution (1 mol L-1), which is much lower than that for the monometallic catalyst (428 mV for amorphous cobalt for the same current density). The bimetal composition of this catalyst induced a strong synergistic effect. Moreover, it exhibited an amorphous and porous structure with a large number of exposed active sites along with high conductivity. These factors contributed to the excellent catalytic performance of this catalyst. This study provides an insight into the design of advanced oxygen evolution reaction catalysts. (C) 2020 Elsevier B.V. All rights reserved.