Ni-decorated Fe-/N- co-doped carbon anchored on porous cobalt oxide nanowires arrays for efficient electrocatalytic oxygen evolution

Abstract

Due to the sluggish four-electron transfer process, the oxygen evolution reaction (OER) kinetics should be speed up to achieve high energy conversion efficiency. The synergistic effect between transition metal heteroatoms and rational interface structural design can effectively enhance the electrocatalytic capability. Herein, utilizing the ZIFs as precursor, we fabricate a simple nickel-decorated three-dimensional Fe-/N- co-doped carbon continuously coated on porous cobalt oxide nanowires array. The partially immersion of carbon into porous CoO can form interlocked interface to enhance the structural stability. The vertically aligned N-doped carbon can facilitate the OH− adsorption, while the Ni-/Fe-/N- co-doped carbon on porous CoO can increase the active sites and enhance the intrinsic electrocatalytic capability. Therefore, the optimal electrode exhibits a low OER onset overpotential of 247.1 mV, low Tafel slope of 38.8 mV dec−1 and robust durability during 60 h test under alkaline condition. This work provides a new feasible strategy for rational structural design of advanced non-precious metal electrocatalysts.