Self-supported iron-doping NiSe2 nanowrinkles as bifunctional electrocatalysts for electrochemical water splitting

Abstract

Designing low-cost and efficient bifunctional electrocatalysts is a great challenge for the clean production of hydrogen energy in electrochemical water splitting. In this study, we reported the preparation of three-dimensional (3D) porous iron-doping NiSe2 nanowrinkles supported on commercial Ni–Fe foam through a facile method of oxalic immersion and subsequent selenization, and investigated the electrocatalytic performance of the catalyst for HER, OER and overall water splitting in alkaline solutions. To drive a current density of 10 mA cm−2, the overpotential is merely 145 mV for HER and 135 mV for OER, and a cell voltage of only 1.58 V is required for overall water splitting in a two-electrode system using the prepared electrocatalyst as both cathode and anode. Meanwhile, the iron-doping NiSe2 catalyst has desirable stability for HER, OER and overall water splitting, and its electrocatalytic performance shows negligible degradation during the durability test. The iron-doping effect, the unique porous nanowrinkle structure, and the in-situ growth of catalyst on the Ni–Fe foam are responsible for the excellent electrochemical performance of the prepared catalyst in water splitting. This work provides new insights for the design of non-noble transition metal chalcogenide catalysts with excellent electrocatalytic performance in overall water splitting.