NiFe/(Ni,Fe)₃S₂ Core/Shell Nanowire Arrays as Outstanding Catalysts for Electrolytic Water Splitting at High Current Densities

Abstract

NiFe/(Ni,Fe)3S2 core/shell nanowire arrays, fabricated with an anodic aluminum oxide membrane templated electrodeposition followed by sulfur ion exchange, are developed as an outstanding catalyst for electrolytic water splitting. Ni nanowire arrays achieve low overpotentials of 112 and 347 mV for the hydrogen evolution reaction at current densities of 10 and 400 mA cm−2, respectively, whereas ultralow overpotentials of 224 and 305 mV for the oxygen evolution reaction at current densities of 10 and 400 mA cm−2, respectively, are achieved by NiFe/(Ni,Fe)3S2 core/shell nanowire arrays. The pairing of the Ni nanowire array electrode as the cathode and the NiFe/(Ni,Fe)3S2 core/shell nanowire array electrode as the anode, delivers current densities of 10 and 400 mA cm−2 at ultralow cell voltages of 1.56 and 1.9 V, respectively, for the overall water splitting. The stability of the electrodes is also excellent, exhibiting only minor chronoamperometric decay after 24 h continuous operation at 400 mA cm−2. The nanowire array‐based electrodes, offering extended reaction surface areas and 1D guided charge transport and mass transfer, prove to be a promising new catalyst architecture design for electrocatalytic processes.

Interfacial Effect on Photo-Modulated Magnetic Properties of Core/Shell-Structured NiFe/NiFe2O4 Nanoparticles

“…It clearly demonstrates that the NiFe nanoparticle has a cubic structure with the p4/mmm space group (Figure 1d). The high-resolution TEM (HRTEM) image in Figure 1c further shows the successful formation of NiFe nanoparticles with a size of about 20 nm, and the inter-planar spacing (0.205 nm) corresponds to the (111) crystal plane of NiFe [31]. By introducing oxygen during rapid thermal annealing, the NiFe/NiFe 2 O 4 core/shell nanoparticles can be successfully fabricated, as shown in Figure 1e.…”

One-step synthesis of mesoporous Cobalt sulfides (CoSx) on the metal substrate as an efficient bifunctional electrode for overall water splitting

“…6a compared the electrocatalytic performance (η10) of some latest reported cobalt-based compounds as bifunctional catalysts for overall water splitting. [5,6,9,19,37,[50][51][52][53][54][55][56][57][58][59] In the figure, these bifunctional catalysts were roughly separated into four different groups according to their sum overpotential value (η10 S ) of HER and OER (η10 S = η10 HER + η10 OER ). The catalysts with a η10 S value below 300 mV were in group I, indicating both fantastic HER and OER performance.…”

A molecular dynamics study on the mechanical properties of Fe–Ni alloy nanowires and their temperature dependence

“…Magnetic nanowires (NWs) have attracted increasing attention for their distinctive properties 1 (magnetic, electrical and mechanical) and show great potential in applications such as ultrahigh-density storage devices, 2 probes, [3][4][5] nanomotors, 6 catalysts, [7][8][9] and electrical devices. 10,11 The design, manufacture, and application of NW-based devices are highly dependent on the mechanical properties of NWs, which are always signicantly different from their bulk counterparts owing to their extremely small diameters and large surface-to-volume ratios.…”