Ternary transition metal of Fe/Co/Ni doping on MoSx nanowires for highly efficient electrochemical oxygen evolution

Abstract

The crucial step for splitting water is the oxygen evolution reaction. The key to promote this reaction lies in the catalyst. Molybdenum disulfide, as a two-dimensional material with molybdenum and sulfur atoms stacked, is especially suitable as a doping platform to develop high-performance OER catalysts. Fe/Co/Ni ternary transition metal combination has always been a highly active catalytic site for OER. Heteroelement of Fe/Co/Ni doping is expected to effectively modify the local electronic configuration of matrix materials and thus enhances their electrocatalytic OER capability. With this in mind, we report a simple in-situ hydrothermal doping of MoSx nanowires on iron‑nickel alloy foam with ternary transition metal of Fe/Co/Ni. This ternary transition metal of Fe/Co/Ni doped f self-supported electrode (denoted Fe/Co/Ni-MoSx/INF) displays outstanding OER performance in terms of small overpotentials of 214 and 263 mV at current densities of 10 and 100 mA/cm2, respectively, in alkaline solution. It was far better than the commercial Ir/C catalysts (253 and 434 mV@10 and 100 mA/cm2). The Tafel slope is about 48.1 mV/dec. Moreover, Fe/Co/Ni-MoSx/INF also has an excellent catalytic stability without any obvious performance decay after 20 h operation. This work contributes to the investigation of high-efficiency OER catalysts based on transition metal-doped MoSx and offers a substitute for noble metal catalysts.