Engineering the Electronic Structure of 2D WS2 Nanosheets Using Co Incorporation as CoxW(1‐x)S2 for Conspicuously Enhanced Hydrogen Generation. Issue 28 (20th June 2016)

• Record Type: Journal Article
• Authors: Shifa, Tofik Ahmed; Wang, Fengmei; Liu, Kaili; Xu, Kai; Wang, Zhenxing; Zhan, Xueying; Jiang, Chao; He, Jun
• Is Part Of: Small. Volume 12:Issue 28(2016)
• Page Start: 3802
• Page End: 3809
• Publication Date: 2016-06-20
• Subjects: chemical vapor deposition -- nanosheets -- hydrogen evolution reaction -- ternary nanosheet -- transition metal dichalcogenides -- hydrogen generation; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.201601168
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract : Transition metal dichalcogenides (TMDs), as one of potential electrocatalysts for hydrogen evolution reaction (HER), have been extensively studied. Such TMD‐based ternary materials are believed to engender optimization of hydrogen adsorption free energy to thermoneutral value. Theoretically, cobalt is predicted to actively promote the catalytic activity of WS2 . However, experimentally it requires systematic approach to form Co x W(1− x ) S2 without any concomitant side phases that are detrimental for the intended purpose. This study reports a rational method to synthesize pure ternary Co x W(1− x ) S2 nanosheets for efficiently catalyzing HER. Benefiting from the modification in the electronic structure, the resultant material requires overpotential of 121 mV versus reversible hydrogen electrode (RHE) to achieve current density of 10 mA cm −2 and shows Tafel slope of 67 mV dec −1 . Furthermore, negligible loss of activity is observed over continues electrolysis of up to 2 h demonstrating its fair stability. The finding provides noticeable experimental support for other computational reports and paves the way for further works in the area of HER catalysis based on ternary materials. Abstract : Metal dopants are believed to manipulate the inherent electronic structure of the host material toward improved activity for hydrogen generation. The purity of the final product is also crucial for the intended purpose. To this aim, pure Co x W(1− x ) S2 nanosheet without any concomitant side phase is fabricated through chemical vapor deposition method. Notably, this material demonstrates superior catalytic performance for hydrogen evolution reaction.