Synthesis of Mo2C and W2C Nanoparticle Electrocatalysts for the Efficient Hydrogen Evolution Reaction in Alkali and Acid Electrolytes.

Sajjad Hussain,Ki-Seok An,Asad Feroze,Wooseok Song,Jongwan Jung,Hyun-Seok Kim,Dhanasekaran Vikraman,Seung-Hyun Chun

doi:10.3389/fchem.2019.00716

Abstract

The synthesis of low cost, high efficacy, and durable hydrogen evolution electrocatalysts from the non-noble metal group is a major challenge. Herein, we establish a simple and inexpensive chemical reduction method for producing molybdenum carbide (Mo2C) and tungsten carbide (W2C) nanoparticles that are efficient electrocatalysts in alkali and acid electrolytes for hydrogen evolution reactions (HER). Mo2C exhibits outstanding electrocatalytic behavior with an overpotential of −134 mV in acid medium and of −116 mV in alkaline medium, while W2C nanoparticles require an overpotential of −173 mV in acidic medium and −130 mV in alkaline medium to attain a current density of 10 mA cm−2. The observed results prove the capability of high- and low-pH active electrocatalysts of Mo2C and W2C nanoparticles to be efficient systems for hydrogen production through HER water electrolysis.

Highlights

A direct and effective route to clean and renewable hydrogen (H2) production by water splitting requires a robust catalyst to ensure sustainable efficiency (Vikraman et al, 2017)
Previous reports suggested that the hydrogen evolution reactions (HER) electrocatalytic performance of Mo2C- and W2C-based catalysts mainly results from the morphology (Ang et al, 2016; Ishii et al, 2016; Peng et al, 2017), crystalline phases (Wan et al, 2014; Lin et al, 2017), and composition (Yu et al, 2018; Zhang et al, 2018) of the catalysts and the synthetic protocol
Raman characterization was performed for structural confirmation of commercial and chemically reduced Mo2C and W2C nanoparticles

Summary

Introduction

A direct and effective route to clean and renewable hydrogen (H2) production by water splitting requires a robust catalyst to ensure sustainable efficiency (Vikraman et al, 2017). Platinum (Pt)based systems are recognized as highly energetic HER catalysts that boast various pH tolerances and almost zero overpotential, but their high cost, originating from the scarcity of platinum, severely hinders their extensive use (Jacobsson et al, 2013; Peng et al, 2014). The critical challenge is to design and develop carbide-based catalysts with comparable catalytic performance to Pt for practical applications. Carbide-based materials have shown inferior catalytic properties due to their poor activities (Wu et al, 2016; Yu et al, 2018; Zhang et al, 2018). Mo2C and W2C nanoparticles with high catalytic activity and robustness remain open for future research

Methods

Results

Conclusion