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Indexed by:期刊论文

Date of Publication:2012-05-01

Journal:NANOSCIENCE AND NANOTECHNOLOGY LETTERS

Included Journals:SCIE、EI、Scopus

Volume:4

Issue:5,SI

Page Number:559-563

ISSN No.:1941-4900

Key Words:Manganese Oxide; Electrochemical Oxidation; Supercapacitor

Abstract:Here we report an in situ electrochemical oxidation method to synthesize birnessite-type MnO2 electrodes for supercapacitors from cathodically deposited Mn3O4 thin films. Mn3O4 thin films composed of nanowall arrays with a porous structure were prepared by cathodic deposition at various temperatures. Nanoparticles were formed within the nanowalls when the deposition temperature is above 50 degrees C, building a nanoparticle/porous hierarchy architecture. Cyclic voltammogram (CV) was used to perform electrochemical oxidation on the Mn3O4 thin film. The birnessite-type MnO2 phase was successfully achieved after the electrochemical CV cyclings, which is believed to be responsible for the significant increase in the specific capacitance of the supercapacitor.