R.Z. Jiang, D.Q. Zhao, H.N. Fan, Y.P. Xie,* M.J. Li, H. Lin, Z.-S. Wu

Journal of Colloid ＆ Interface Science, 2021, 606, 384-392.

DOI: 10.1016/j.jcis.2021.08.035 [PDF]

Earth-abundant transition metal-based bifunctional electrocatalysts are promising alternatives to noble metals for overall water electrolysis, but restricted by low activity anddurability. Herein, a three-dimensional phosphorus-doped nickel molybdate/nickel molybdate hydrate@phosphates core-shell nanorod clusters on nickel foam self-supported electrode was fabricated by a combined hydrothermal and phosphating process. The phosphorus doping and phosphatecoatinginduced byphosphatingprocess bring in a synergistic effect to improve the electrical conductivity, provide abundant active surface sites and accelerate the surface reaction for nickel molybdate/nickel molybdate hydrate(NiMoO₄/NiMoO₄·nH₂O)heterostructures. These advantages enable the self-supported electrode to exhibit high hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activity in 1.0 M KOH with low overpotentials of 148 and 260 mV at 10 mAcm^-2, respectively. When it was employed both as anode and cathode, a cell voltage of 1.62 V is only required to reach the current density of 10 mAcm^-2in alkaline solution. Especially, the self-supported electrode reveals outstanding durability, which could maintain over 25 h at 10 mAcm^-2for HER, OER or overall water splitting. This work provides a novel avenue to enhance the electrocatalytic performance of the catalysts by synergistically modulating the intrinsicelectrical conductivity, activesurfacesites and surface reaction.