Nanostructured Tungsten Oxysulfide as an Efficient Electrocatalyst for Hydrogen Evolution Reaction

Abstract

Transition metal oxysulfides (TMOS) exhibit promising catalytic properties for hydrogen evolution reactions (HER). However, the development of facile and controllable routes for obtaining nanostructured TMOS under ambient conditions still remains a significant challenge. Here we report a simple and controllable route to synthesize nanoparticles of tungsten oxysulfides (WO x S y ) that exhibit enhanced electrocatalytic activity toward HER with outstanding stability. The sulfur-rich tungsten oxysulfides with engineered anionic species can offer multiple functionalities, including abundant active sites and improved conductivity that synergistically contribute to enhanced electrocatalytic activity for HER. The optimized WO x S y electrocatalyst shows low overpotential of 103 mV at a current density of 10 mA cm–2, along with a Tafel slope of 54 mV decade–1 and 5.89 × 10–2 mA cm–2 exchange current density. Density functional theory (DFT) based calculations further establish the improved catalytic activity of tungsten oxysulfide (WO x S y ), compared to the pristine 1T-WS2, based on the free energy calculations. The present work demonstrates a highly promising approach toward the development of cost-effective, efficient, and durable electrocatalysts to replace precious metals for electrocatalytic hydrogen generation.

Liquid metals: an ideal platform for the synthesis of two-dimensional materials

“…While complete sulphurisation was not achieved, metal oxysulphides are increasingly being investigated for electronic applications and catalysis. [95][96][97] This study not only highlights the compositional tunability of these 2D indium oxysulphide nanosheets, but also reveals a possible synthesis route for other 2D metal oxysulphide materials, including bismuth oxysulphide and tin oxysulphide. Other reactive species may also be used to significantly expand the library of 2D materials that are accessible via this furnace-free method, particularly if reactive pnictogen and chalcogen species are utilised.…”

[NiFe]-(Oxy)Sulfides Derived from NiFe2O4 for the Alkaline Hydrogen Evolution Reaction

“…The obtained electrocatalysts displayed sulfur-content-dependent HER activity, with the highest activity for CoO x S 0.18 . Another oxysulfide material was synthesized by Sarma et al by the anodic oxidation of WS 2 sheets [17]. Here, distinct WO x S y materials were obtained depending on the deposition potential, which has shown the highest HER performance for the WO x S y material, which was deposited at 5 V.…”

Design Principles for Tungsten Oxide Electrocatalysts for Water Splitting

“…Therefore, promoted by its strong structural modulability, tungsten oxide is considered as a potential electrocatalyst for water splitting. Recently, much research relative to tungsten oxide is mainly focused on the structure design and modification to improve reactive activity and stability in electrocatalytic water splitting [25–27] . Even so, there is lack of an overview on systematic and comprehensive understanding on the structure‐activity relationship of tungsten oxide as electrocatalyst for water splitting.…”

“…Recently, much research relative to tungsten oxide is mainly focused on the structure design and modification to improve reactive activity and stability in electrocatalytic water splitting. [25][26][27] Even so, there is lack of an overview on systematic and comprehensive understanding on the structureactivity relationship of tungsten oxide as electrocatalyst for water splitting. In this review, we summarize the latest advances in tungsten oxide catalyst for water splitting, in terms of the reaction mechanism, structure modulation and catalytic performance in HER and OER.…”