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Nanosized tungsten carbide synthesized by a novel route at low temperature for high performance electrocatalysis.

ABSTRACT: Tungsten carbide (WC) is a widely used engineering material which is usually prepared at high temperature. A new mechanism for synthesizing nanoscaled WC at ultralow temperature has been discovered. This discovery opens a novel route to synthesize valuable WC and other carbides at a cost-efficient way. The novel formation mechanism is based on an ion-exchange resin as carbon source to locally anchor the W and Fe species. As an intermediate, FeWO4 can be formed at lower temperature, which can be directly converted into WC along with the carbonization of resin. The size of WC can be less than 2?nm. The catalyst made with Pt nanoparticles supported on nanosized WC-GC (WC-graphitized carbon) shows enhanced electrocatalytic activity for oxygen reduction reaction. The result also indicates that the Pt nanoparticles deposited on WC-GC are dominated by Pt (111) plane and shows a mass activity of 257.7?mA mg(-1)Pt@0.9?V.

SUBMITTER: Yan Z

PROVIDER: S-EPMC3622077 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Nanosized tungsten carbide synthesized by a novel route at low temperature for high performance electrocatalysis.

Yan Zaoxue Z Cai Mei M Shen Pei Kang PK

Scientific reports 20130101

Tungsten carbide (WC) is a widely used engineering material which is usually prepared at high temperature. A new mechanism for synthesizing nanoscaled WC at ultralow temperature has been discovered. This discovery opens a novel route to synthesize valuable WC and other carbides at a cost-efficient way. The novel formation mechanism is based on an ion-exchange resin as carbon source to locally anchor the W and Fe species. As an intermediate, FeWO4 can be formed at lower temperature, which can be ...[more]

PMID: 23571654

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