Summary: Multisegmented Au-MnO2/Carbon Nanotube Hybrid Coaxial Arrays for High-Power
Arava Leela Mohana Reddy,
Manikoth M. Shaijumon,
Sanketh R. Gowda,
Pulickel M. Ajayan*,
Department of Mechanical Engineering & Materials Science, and Department of Chemical and Biomolecular
Engineering, Rice UniVersity, 6100 Main Street, Houston, Texas 77005
ReceiVed: September 9, 2009; ReVised Manuscript ReceiVed: NoVember 4, 2009
The present work reports on synthesis and supercapacitor applications of multisegmented Au-MnO2/carbon
nanotube (CNT) coaxial arrays. Multisegmented Au-MnO2/CNT coaxial arrays are fabricated inside porous
alumina templates using a combination of electrodeposition, infiltration, and chemical vapor deposition methods.
CNTs serve as an alternative additive for improving the electrical conductivity of the manganese oxide
electrodes, in addition to its active electrode characteristics. The well-adhered interface between Au and MnO2/
CNT hybrid segments leads to nanoscale electrical contacts between the electrode and current collectors.
Electrochemical studies have been performed using cyclic voltammetry, galvanostatic charge-discharge, and
impedance spectroscopy measurements. The results demonstrate that MnO2/CNT hybrid coaxial arrays are
efficient electrodes for supercapacitor applications. Au-segmented MnO2/CNT hybrid coaxial electrodes showed
further improvement in specific capacitance, energy, and power densities of a supercapacitor.