A Redox-anchoring Approach to Well-dispersed MoC_x/C Nanocomposite for Efficient Electrocatalytic Hydrogen Evolution

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• 作者：Dr. Yajun Zhou ; Dr. Lingxia Zhang ; Dr. Weimin Huang ; Dr. Min Wang ; Dr. Lisong Chen ; Dr. Xiangzhi Cui ; Dr. Xiaohua Zhang and Prof. Jianlin Shi
• 刊名：Chemistry – An Asian Journal
• 出版年：2017
• 出版时间：February 16, 2017
• 年：2017
• 卷：12
• 期：4
• 页码：446-452
• 全文大小：1652K
• ISSN：1861-471X

文摘

Here we report a redox-anchoring strategy for synthesizing a non-noble metal carbide (MoC_x) nanocomposite electrocatalyst for water electrolysis in acidic media, using glucose and ammonium heptamolybdate as carbon and Mo precursors, respectively, without the need of gaseous carbon sources such as CH₄. Specifically, the aldehyde groups of glucose are capable of reducing Mo⁶⁺ to Mo⁴⁺ (MoO₂), and thus molybdenum species can be well anchored by a redox reaction onto a carbon matrix to prevent the aggregation of MoC_x nanoparticles during the following carbonization process. The morphology and chemical composition of the electrocatalysts were well characterized by BSE-SEM, TEM, XRD and XPS. The obtained MoC_x−2 sample showed a reasonably high hydrogen evolution reaction (HER) activity and excellent stability in an acidic electrolyte, and its overpotential required for a current density output of 20 mA cm⁻² is as low as 193 mV. Such a prominent performance is ascribed to the excellent dispersity and nano-size, and the large reactive surface area of MoC_x particles. This work may open a new way to the design and fabrication of other non-noble metal carbide nanocatalysts for various electrochemical applications.