Construction of amorphous CoFeOx(OH)y/MoS2/CP electrode for superior OER performance

Design and direct construction of oxygen evolution reaction (OER) catalyst-based electrode is an efficient route to improve the water splitting reaction. Herein, we proposed a facile route to synthesize and load the composite of amorphous CoFe oxyhydroxide (CoFeO_x(OH)_y) and MoS₂ on the carbon paper by combining a hydrothermal and an electrodeposition process. CoFeO_x(OH)_y has a special feature of long-range disorder (amorphous phase) and short-range order (crystal phase), which greatly improves the OER catalytic performance of the hybrids. In virtue of the synergistic effect of CoFeO_x(OH)_y and MoS₂, an improved electronic coupling effect occurs, which increases the oxidation state of Co and Fe, and thus enhances OER activity. As-synthesized CoFeO_x(OH)_y/MoS₂/CP (CFOMS/CP) electrode affords excellent electrocatalytic activity and good electrochemical OER stability: A small Tafel slope of 37.9 mV dec^?1 (vs. 62.1 mV dec^?1 for CoFeO_x(OH)_y/CP, 120.2 mV dec^?1 for RuO₂/CP) and low overpotential 242 mV at 10 mA cm^?2 (vs. 263 mV for CoFeO_x(OH)_y/CP, 317 mV for RuO₂/CP), as well as a stable running for 25 h.