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Title: Hydrothermal synthesis of hierarchical microstructure tungsten oxide/carbon nanocomposite for supercapacitor application
Abstract

A hierarchical nanocomposite of carbon microspheres decorated with tungsten oxide (WO3) nanocrystals resulted from the hydrothermal treatment of a precursor solution containing glucose and tungstic acid. The dehydration of glucose molecules formed oligosaccharides, which consequently carbonized, turning into carbon microspheres. The carbon microspheres then acted as a spherical nucleus onto which WO3nanocrystals grew via heterogeneous nucleation. The reaction product showed a phase junction of orthorhombic and monoclinic WO3,which transitioned to mix-phase of tetragonal and monoclinic WO3after a subsequent heat treatment at 600 °C in an inert condition. The electrochemical tests showed that incorporating WO3onto the carbon (WO3/C) resulted in a three-fold increase in the specific capacitance compared to WO3alone and a high coulombic and energy efficiencies of 98.2% and 92.8%, respectively. The nanocomposite exhibited supercapacitance with both Faradaic and non-Faradaic charge storage mechanisms. Electrochemical impedance spectroscopy showed a lower charge transfer resistance for the composite at Rct = 11.7Ω.

 
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Award ID(s):
2000310
PAR ID:
10478543
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Scientific Reports
Volume:
13
Issue:
1
ISSN:
2045-2322
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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