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• Stainless steel mess with a three-dimensional network structure substrate to grow NiCoP-CoP electroactive catalyst. • NiCoP@SSM electrocatalyst reveals an excellent performance and stability towards hydrogen evolution reaction. • Synergetic effect between Pδ− with a high affinity towards proton-acceptor, and Coδ+/ Niδ+ as hydride-acceptor. The stainless steel mesh (SSM) has received remarkable attention for hydrogen and oxygen evolution reactions. It was demonstrated that the SSM exhibits admirable performance towards oxygen evolution reaction (OER) electrocatalysis, while its catalytic activity for hydrogen evolution reaction (HER) remains quite low. This obstructs the utilization of SSM-based catalysts for sustainable complete water electrolysis. In this study, a facile hydrothermal route followed by a phosphorization process was adopted to transform commercially available SSM materials into high-performance and stable electrocatalysts for alkaline HER. We report an interconnected NiCoP-CoP sponge-like structure on SSM substrate without polymer binder. Benefiting from the 3D construction with high exposed surface area, close contact between electroactive species and conductive surface, and facilitated infiltration of electrolyte, the as-prepared NiCoP@SSM electrocatalyst brought an improved catalytic activity for HER, required a low overpotential of 138 mV to derive a current density of 10 mAcm−2 in 1.0 M KOH aqueous solution. The high performance of the NiCoP@SSM catalyst has also unveiled fast reaction kinetics (presents a small Tafel slope of 74 mV/dec), a relatively large electrochemical active surface area (ECSA), and small charge transfer resistance. Furthermore, the NiCoP@SSM electrode also presented excellent stability during long-term measurements, making it one of the most encouraging HER electrodes to date. This research study paves the way for the development of HER-active electrocatalysts made from SSMs that are commercially available, low-cost, and highly active. [Display omitted] [ABSTRACT FROM AUTHOR] more...

[Display omitted] • Facile approach to transform NiFe 2 O 4 into N -doped carbon decorated-Ni 3 Fe@Fe 3 O 4. • Polydopamine effect on the overall structure and OER performance of NiFe 2 O 4. • Ni 3 Fe and Fe 3 O 4 active sites provide favorable reaction kinetic and stability. High performance, durable and inexpensive electrocatalyst for oxygen evolution reaction (OER) is of great importance for tenable hydrogen production via water electrolysis. Although spinel oxides (AB 2 O 4 , A, B = metal) represent a class of promising candidates for OER, their intrinsically poor electrical conductivity impacts their electrochemical performance. Herein, we employed a facile approach to transform an intrinsically low active NiFe 2 O 4 into nitrogen-doped carbon decorated Ni 3 Fe@Fe 3 O 4 catalyst with improved activity and stability for alkaline OER. Initially, a pristine NiFe 2 O 4 octahedron-like structure was synthesized by a hydrothermal route. Then, series electrocatalysts were prepared by incorporating the pristine NiFe 2 O 4 with different dopamine concentrations via in-situ polymerizations of dopamine followed by carbonization. The morphology, crystalline structure, and chemical composition of the catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma (ICP). The OER electrocatalysis performance was measured in a standard three-electrode system. The effect of the carbonized dopamine on the electrocatalytic activity and structure of the NiFe 2 O 4 precursor was systematically investigated. Among several NiFe electrocatalysts, the one with 10 wt% of dopamine (NiFe/NC 10%) exhibited a relatively higher catalytic activity for OER tested in 1.0 M KOH; unveiled low overpotential (350 mV at 10 mAcm−2 current density), a low Tafel slope (56 mVdec−1), low charge transfer resistance, relatively higher electrochemically active surface area. Most prominently, it remained stable for at least 12 h. This work provides a new perspective for functionalizing metal oxides and affords a facile synthesis approach, low-cost, high-performance, and robust electrocatalyst for alkaline OER electrodes. [ABSTRACT FROM AUTHOR] more...