W-Doped Ni₃S₂ Nanoparticles Modified with NiFeLa Hydroxide for Hydrogen Evolution

For achieving long duration and high efficiency of hydrogen evolution reaction (HER) catalysts, the key mainly lies in constructing porous structures, improving conductivity, and tailoring chemical components. Inspired by this, we in situ deposited W-doped Ni3S2 nanoparticles modified with NiFeLa hydroxide on Ni foam (NF). Our work primarily concentrates on optimizing the dosage of W element and constructing open nanostructures with rich active sites. The internal W-doped Ni3S2 nanoparticles enable high conductivity, and the outer NiFeLa hydroxide nanosheets form more active sites, which help to monitor the electronic structure and generate synergistic effects. Both optimization of tungsten hexachloride dosage and epitaxial growth of NiFeLaOH nanosheets greatly ameliorate the surface active area, conductivity, and electronic structure of the hybrid nanomaterial. When directly applied to alkaline HER catalytic systems, the resulting catalyst presents favorable electrochemical performance, such as low HER overpotentials (67 mV at 10 mA cm–2 and 330 mV at 552 mA cm–2). Remarkably, after a duration of 40 h, the catalytic activity presents pretty slight attenuation (amplification of ∼15 mV for overpotential), which indicates its ultralong stability. This research introduces an effective method to tune electrocatalytic performance by doping W element into Ni3S2 and coupling with NiFeLa hydroxide.