Nickel-doped pyrrhotite iron sulfide nanosheets as a highly efficient electrocatalyst for water splitting

Abstract

The synthesis of highly activity, stable and cost-effective electrocatalysts for overall water splitting is critical but challenging. Herein, we synthesized the nickel-doped pyrrhotite iron sulfide (Fe0.95−xNixS1.05) nanosheets via a one-pot...

(Fe,Ni)9S8 Nanosheets on a Three‐Dimensional Conductive Substrate for Efficient Oxygen Evolution Reaction Electrocatalysis

“…It has been well studied that the synergistic electronic interplay between Fe and Ni can modify the adsorption process of the intermediates during OER, thus accelerate the reaction kinetics and enhance the electrocatalytic efficiency [11b,20,45] . In addition, the synergistic effect of Fe and Ni also plays an important role in determining the surface morphology to expose more active sites and facilitate charge transfer [46] . (c) the nanosheets morphology along with the 3D substrate provides a larger active specific surface area and expose more active sites for efficient charge and mass transfer [21] .…”

Novel WS2/Fe0.95S1.05 Hierarchical Nanosphere as a Highly Efficient Electrocatalyst for Hydrogen Evolution Reaction

“…[32,38] This indicates that the prepared catalyst exhibits the mixed valence characteristics of Fe 2 + and Fe 3 + . [24] The satellite peak that are observed at 727.5 eV and 715.2 eV are attributed to Fe 2 + sat. and Fe 3 + sat.…”

“…These electrochemical data indicate that the excellent HER performance of the WS 2 / Fe 0.95 S 1.05 -2 hybrid catalyst can be attributed to the good electron transfer rate and larger ECSA. [24] After performing the HER test, XPS were conducted to analyze the WS 2 /Fe 0.95 S 1.05 -2 hybrid catalyst. The XPS spectrum of WS 2 /Fe 0.95 S 1.05 hybrid catalyst W, Fe, S, C, and O elements were studied (Figure S6a).…”

“…Figure S6c shows the XPS spectra of Fe 2p in WS 2 / Fe 0.95 S 1.05 -2 hybrid catalyst after HER test, Fe 2p 1/2 peak and Fe 2p 3/2 respectively appeared at 724.1 eV and 712.3 eV, while the peak of 720 eV is for Fe sat. [24] As shown in Figure S6d, underwent stability test, an oxidation peak of S appeared at 169.2 eV; the position of the S 2À peak at 164.2 eV remained unchanged compared with WS 2 /Fe 0.95 S 1.05 -2 hybrid catalyst before HER test. [7a] Through the XPS spectra of W 4 f, Fe 2p and S 2p, confirming that the WS 2 /Fe 0.95 S 1.05 -2 hybrid catalyst has good stability, which is consistent with TEM image after HER test (Figure S7a).…”

“…On the other hand, the toxicity of Fe is relatively low, and it does not pollute the environment during research and experiment [21a,23] . Taking ferrotungsten sulfide as an example, the occupied low‐spin d‐orbital of W 4+ can release π electrons to the high‐spin d orbital of Fe 2+ to improve HER performance [24] . This indicates that coupling a W‐based catalyst and an Fe‐based catalyst is likely to increase HER activity [25] .…”