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Updated: Feb 2, 2026

Scalable Syntheses of Graphene Oxide and Reduced Graphene Oxide using Cascade Design Oxidation and Highly Basic Reduction Reactions
Published on: July 3, 2025
WS(1-Se Nanoparticles Decorated Three-Dimensional Graphene on Nickel Foam: A Robust and Highly Efficient
Sajjad Hussain1,2, Kamran Akbar3,4, Dhanasekaran Vikraman5
1Graphene Research Institute, Sejong University, Seoul 05006, Korea. hussain@sejong.ac.kr.
Abstract:
To find an effective alternative to scarce, high-cost noble platinum (Pt) electrocatalyst for hydrogen evolution reaction (HER), researchers are pursuing inexpensive and highly efficient materials as an electrocatalyst for large scale practical application. Layered transition metal dichalcogenides (TMDCs) are promising candidates for durable HER catalysts due to their cost-effective, highly active edges and Earth-abundant elements to replace Pt electrocatalysts. Herein, we design an active, stable earth-abundant TMDCs based catalyst, WS(1-Se nanoparticles-decorated onto a 3D porous graphene/Ni foam. The WS(1-Se/graphene/NF catalyst exhibits fast hydrogen evolution kinetics with a moderate overpotential of ~-93 mV to drive a current density of 10 mA cm-2, a small Tafel slope of ~51 mV dec-1, and a long cycling lifespan more than 20 h in 0.5 M sulfuric acid, which is much better than WS₂/NF and WS₂/graphene/NF catalysts. Our outcomes enabled a way to utilize the TMDCs decorated graphene and precious-metal-free electrocatalyst as mechanically robust and electrically conductive catalyst materials.
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