title: Atomic layer deposition of ruthenium on plasma-treated vertically aligned carbon nanotubes for high-performance ultracapacitors.
abstract: It is challenging to realize a conformal metal coating by atomic layer deposition (ALD) because of the high surface energy of metals. In this study, ALD of ruthenium (Ru) on vertically aligned carbon nanotubes (CNTs) was carried out. To activate the surface of CNTs that lack surface functional groups essential for ALD, oxygen plasma was applied ex situ before ALD. X-ray photoelectron spectroscopy and Raman spectroscopy confirmed surface activation of CNTs by the plasma pretreatment. Transmission electron microscopy analysis with energy-dispersive x-ray spectroscopy composition mapping showed that ALD Ru grew conformally along CNTs walls. ALD Ru/CNTs were electrochemically oxidized to ruthenium oxide (RuOx) that can be a potentially useful candidate for use in the electrodes of ultracapacitors. Electrode performance of RuOx/CNTs was evaluated using cyclic voltammetry and galvanostatic charge-discharge measurements.
authors.affiliation: School of Mechanical Engineering, Korea University, Seoul 136-713, Korea.
authors.forename: Jun Woo
authors.initials: JW
authors.lastname: Kim
authors.forename: Byungwoo
authors.initials: B
authors.lastname: Kim
authors.forename: Suk Won
authors.initials: SW
authors.lastname: Park
authors.forename: Woong
authors.initials: W
authors.lastname: Kim
authors.forename: Joon Hyung
authors.initials: JH
authors.lastname: Shim