Comparative study on various morphologies of WS2 for electrochemical hydrogen evolution reaction

Abstract

Nowadays, the advancement of cost-effective and efficient electrocatalysts holds significant importance in facilitating the progress of high-performance electrochemical hydrogen evolution reaction (HER). Tungsten disulfides (WS2) are well recognized as highly promising electrocatalysts for HER due to their exceptional catalytic performance, outstanding stability, and comparatively affordable price. In this study, we used ammonium metatungstate hydrate and thioacetamide as precursors to fabricate WS2 nanoflowers (NFs) by hydrothermal method, whereas WS2-flakes were prepared from ammonium tetrathiotungstate through the thermolysis technique. These structures were evaluated for HER electrocatalytic activity in acidic media. The results revealed that WS2-NFs exhibit higher catalytic activity than WS2-flakes, with an overpotential of 325 mV to obtain a current density of 10 mA cm−2 and a Tafel slope of 92.3 mV dec−1. This performance was attributed to the larger electrochemically active surface area of WS2-NFs compared to WS2-flakes materials. The results of this study could bring the basis for further studies on the synthesis of WS2-based catalytic materials for HER. ® 2023 Journal of Science and Technology - NTTU