MoO_xS_y/Ni₃S₂ Microspheres on Ni Foam as Highly Efficient, Durable Electrocatalysts for Hydrogen Evolution Reaction

Abstract

Hydrogen energy derived from water splitting is the cleanest renewable energy source, but it is also very challenging to achieve because the hydrogen evolution reaction (HER) requires highly efficient and low-cost electrocatalysts. We have fabricated a novel hierarchical system of amorphous molybdenum oxy/sulfide microspheres with crystalline Ni3S2 intergrown in situ on Ni foam (MoO x S y /Ni3S2/NF) as an outstanding electrocatalyst for HER. The MoO x S y /Ni3S2/NF demonstrates an ultra-low overpotential of 58 mV at a current density of 10 mA cm–2 and extremely durable stability (>200 h), suggesting superior performance comparable to that of Pt-C/NF under acidic conditions. The X-ray absorption fine structure (XAFS) determines the average valence state of Mo to be +(5 + δ), with a coordination motif by O and S. To explain such high HER activity, a [Mo2O2(S,O)4] dimer-based periodic model structure with the average composition of [Mo4O8S4] interfaced with the Ni3S2(101) surface is proposed. The interactions between the Ni of Ni3S2 and bridging S/O of [Mo4O8S4] result in an average formal Mo charge state between +5 and +6, and significant charge transfer from Ni3S2 to [Mo4O8S4] activates the MoO bonds. The calculated |ΔG H*| of less than 50 meV suggests that the double-bonded O is the most active site. This work points to the importance of oxy/sulfides with Mo n+ (+5 < n<+6) as exceptional electrochemical catalysts for HER.

Ru@Ni3S2 nanorod arrays as highly efficient electrocatalysts for the alkaline hydrogen evolution reaction

“…Therefore, various Ni 3 S 2 -based heterostructures have been developed for the electrocatalytic hydrogen evolution reaction. 8,[28][29][30][31][32][33] Feng et al designed Cu nanodot-decorated Ni 3 S 2 nanotubes supported on carbon fibers as efficient electrocatalysts for the HER in alkaline media. The strong synergistic effect between Cu nanodots and Ni 3 S 2 nanotubes endows the hybrid electrocatalyst with excellent HER catalytic performance.…”

“…Therefore, various Ni 3 S 2 -based heterostructures have been developed for the electrocatalytic hydrogen evolution reaction. 8,28–33 Feng et al . designed Cu nanodot-decorated Ni 3 S 2 nanotubes supported on carbon fibers as efficient electrocatalysts for the HER in alkaline media.…”

Construction of Artificial Light-Harvesting Systems Based on Aggregation-Induced Emission Type Supramolecular Self-Assembly Metallogels

“…With the gradually increasing demand for energy and the massive consumption of conventional fossil fuels, the development of clean and sustainable energy resources has become increasingly important . As a solution to the energy crisis, we need to seek sustainable alternative energy sources. , As a form of clean and sustainable energy, solar energy has been attracting significant interest from the science and technology research community .…”

“…The precipitate was collected by filtration, washed with water, and dried, yielding compound P1 as a purple solid (1.8435 g, yield: 20%). 1 H NMR (400 MHz, DMSO-d 6 , Figure S1): δ (ppm): 13.01 (s, 2H), 8.36 (s, 4H), 7.71 (d, J = 7.4 Hz, 2H), 7.57 (d, J = 7.2 Hz, 2H), 7.24 (d, J = 7.2, 5.9 Hz, 4H). 13 C NMR (101 MHz, DMSO-d 6 , Figure S2): δ (ppm) = 151.07, 144.…”

3d Transition metal doping induced charge rearrangement and transfer to enhance overall water-splitting on Ni3S2(101) facet: a first-principles calculation study

“…The low-index (101) facet is energetically stable, can be easily achieved experimentally, and displays plausible catalytic activity. 16,20,21 Doping with impurities is one practical strategy to improve the catalytic activity 22,23 Yuan et al obtained Fe-Ni 3 S 2 /FeNi based on the one-step direct growth of metallic iron-nickel sulde nanosheets on FeNi alloy foils, which exhibited high catalytic activity and long-term stability toward OER with a low overpotential of 282 mV at 10 mA cm À2 and a small Tafel slope of 54 mV dec À1 . 12 Wang et al prepared a series of selfsupporting M-NiCo 2 S 4 /Ni 3 S 2 (M ¼ Mn, Fe, Cu, Zn) nanostructures grown on a nickel foam (NF) skeleton through a onestep hydrothermal strategy.…”