Single-Atom Tungsten Doped Nis0.5Se0.5 Nanosheets@Nanorods Heterostructures Catalyze Water Splitting Highly Active and Durable

Abstract

Developing robust nonprecious electrocatalysts towards hydrogen/oxygen evolution reaction (HER/OER) is crucial for the spread of hydrogen energy industrialization. Here, we prepared a highly active and durable electrocatalyst of W single-atoms doped NiS0.5Se0.5 nanosheets@NiS0.5Se0.5 nanorods heterostructure (W-NiS0.5Se0.5). The W-NiS0.5Se0.5 exhibits superior catalytic activity for HER and OER with an ultralow overpotential (39, 106 mV for HER and 171, 239 mV for OER) and excellent long-term durability (500 h) at 10 and 100 mA cm− 2, outperforming commercial precious-metal catalysts and many other reported transition-metal-based compounds. The spin state of Ni was delocalized by introducing low spin-state of W single-atom, thus increasing the electron density of Ni 2p orbital, optimizing the adsorption/desorption process of H, significantly reducing the energy barrier of the rate-determining step (O* → OOH*), finally accelerating thermodynamics and kinetics of HER/OER. This work provides a rational feasible strategy to design single-atom catalysts for water splitting and develop advanced transition metal-based electrocatalysts via regulating delocalized spin states.

Tungsten-Based Nanocatalysts: Research Progress and Future Prospects

“…Developing a kind of electrocatalyst toward HER/OER is crucial for the spread of hydrogen energy industrialization. Herein, Wang et al [ 35 ] prepared a W single-atom-doped heterostructure grown on nickel foam (NF), denoted as W-NiS 0.5 Se 0.5 . The HER performances were tested in 1.0 M KOH, showing that W-NiS 0.5 Se 0.5 exhibits a lower overpotential of 39 mV to reach 10 mA/cm 2 , which is comparable to commercial Pt/C (36 mV).…”

Engineering Cu/NiCu LDH Heterostructure Nanosheet Arrays for Highly-Efficient Water Oxidation

“…In recent years, many transition metal rich OER catalysts, such as 3D transition metal layered double hydroxides (LDH) [11,12], spinel oxides [13,14], selenide [8,14,15], sulfide [16,17], phosphide [18,19], etc., are expected to be used as highly active electrocatalysts for oxygen evolution reaction (OER). Recently, LDH based on 3D transition metals (especially Fe, Co, Mn, Ni) have been reported to exhibit excellent OER catalytic performance.…”