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Low cost and highly efficient bifuctional catalysts for overall water electrolysis have drawn considerable interests over the past several decades. Here, rationally synthesized mesoporous nanorods of nickel–cobalt–iron–sulfur–phosphorus composites are tightly self‐supported on Ni foam as a high‐performance, low cost, and stable bifunctional electrocatalyst for water electrolysis. The targeted designing and rational fabrication give rise to the nanorod‐like morphology with large surface area and excellent conductivity. The NiCoFe‐PS nanorod/NF can reach 10 mA cm−2 at a small overpotential of 195 mV with a Tafel slope of 40.3 mV dec−1 for the oxygen evolution reaction and 97.8 mV with 51.8 mV dec−1 for the hydrogen evolution reaction. Thus, this bifunctional catalyst shows low potentials of 1.52 and 1.76 V at 10 and 50 mA cm−2 toward overall water splitting with excellent stability for over 200 h, which are superior to most non‐noble metal‐based bifunctional electrocatalysts recently. This work provides a new strategy to fabricate multiple metal‐P/S composites with the mesoporous nanorod‐like structure as bifunctional catalysts for overall water splitting.

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Synthesis of highly efficient and stable electrocatalysts for oxygen evolution reaction remains a big challenge. Herein, we rationally designed a novel route, involving hydrothermal electrodeposition of Ni/Zn alloy and in situ electrochemical dealloying followed by sulfuration, to fabricate three-dimensional mesoporous nickel sulfide nanosheets assembled tightly on Ni foam for oxygen evolution reaction. The mesoporous Ni 3 S 2 nanosheets/Ni foam exhibited a highly mesoporous structure with a specific surface area of 60.1 m 2 g −1 and showed a low overpotential of 223 mV at a current density of 10 mA cm −2 with a small Tafel slope of 60.5 mV dec −1 ; this overpotential is superior to that of IrO 2 /Ni foam. As-prepared Ni 3 S 2 nanosheets/Ni foam achieved a high turnover frequency value of 0.61 mol O 2 s −1 at an overpotential of 500 mV. Impressively, the as-obtained catalyst possessed excellent conductivity and outstanding stability for over 240 h. The superior catalytic property could be ascribed to the rational synthetic process, morphology-controlled mesoporous structure, and highly exposed active sites. This paper presents an efficient route to fabricate porous nanosheets as stable and efficient electrocatalyst for water oxidation.