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Updated: Sep 18, 2025
Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics
Published on: April 12, 2019
Interfacial engineering and electronic structure modulation of two-dimensional WSe2 towards improved electrocatalytic
Hrudeswar Mohanty1, Sellappan Senthilkumar1
1Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology (VIT), Vellore, 632014, India. senthilkumar.s@vit.ac.in.
Abstract:
Tungsten diselenides (WSe2) are regarded as highly desirable catalysts for various electrochemical reactions, owing to their tuneable conductivity and high electrochemical stability. A variety of strategies are continuously being explored to tune their electrochemical properties and to further enhance their electrocatalytic performance. Interface engineering is an ingenious approach for enhancing the electrocatalytic properties of transition metal dichalcogenides (TMDs). Thus, in the present investigation, we intend to tune the interlayer spacing of WSe2 nanosheets (NSs) for modulating their electronic properties and to examine its influence on the electrocatalytic hydrogen evolution reaction (HER). Initially, WSe2 NSs with different interlayer spacing were obtained either without or with different organic inclusion compounds, viz. oleyl amine (OA), glucose (Glu) and ammonium oxalate (AOx), incorporated during the solvothermal synthesis. The prepared WSe2 NSs were systematically characterized using different structural and morphological investigations. The WSe2 prepared without any inclusion compound exhibited an interlayer spacing of 0.62 nm, whereas WSe2-OA, WSe2-Glu and WSe2-AOx showed interlayer spacing of 0.59, 0.69 and 0.75 nm, respectively. The inherent electrochemical characteristics of the prepared WSe2 NSs and their electrocatalytic efficacy towards the HER were studied in 0.5 M H2SO4. Among these, WSe2-AOx demonstrated impressive catalytic performance with a low overpotential of 268 mV at a current density of 10 mA cm-2 and a low Tafel slope of 94 mV dec-1. The superior electrocatalytic activity observed with WSe2-AOx is attributed to the largest interlayer spacing which exposed abundant catalytic sites on the basal planes, thereby accelerating the kinetics of the HER. Notably, WSe2-AOx displayed excellent cycling stability for 1000 cycles and impressive long-term stability up to 12 h in 0.5 M H2SO4.
