title: TiO2, SiO2, and Al2O3 coated nanopores and nanotubes produced by ALD in etched ion-track membranes for transport measurements.
abstract: Low-temperature atomic layer deposition (ALD) of TiO2, SiO2, and Al2O3 was applied to modify the surface and to tailor the diameter of nanochannels in etched ion-track polycarbonate membranes. The homogeneity, conformity, and composition of the coating inside the nanochannels are investigated for different channel diameters (18-55 nm) and film thicknesses (5-22 nm). Small angle x-ray scattering before and after ALD demonstrates conformal coating along the full channel length. X-ray photoelectron spectroscopy and energy dispersive x-ray spectroscopy provide evidence of nearly stoichiometric composition of the different coatings. By wet-chemical methods, the ALD-deposited film is released from the supporting polymer templates providing 30 μm long self-supporting nanotubes with walls as thin as 5 nm. Electrolytic ion-conductivity measurements provide proof-of-concept that combining ALD coating with ion-track nanotechnology offers promising perspectives for single-pore applications by controlled shrinking of an oversized pore to a preferred smaller diameter and fine-tuning of the chemical and physical nature of the inner channel surface.
authors.affiliation: Materialforschung, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany. Material- und Geowissenschaften, Technische Universität Darmstadt, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Spende
authors.forename: Nicolas
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authors.lastname: Sobel
authors.forename: Manuela
authors.initials: M
authors.lastname: Lukas
authors.forename: Robert
authors.initials: R
authors.lastname: Zierold
authors.forename: Jesse C
authors.initials: JC
authors.lastname: Riedl
authors.forename: Leonard
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authors.lastname: Gura
authors.forename: Ina
authors.initials: I
authors.lastname: Schubert
authors.forename: Josep M Montero
authors.initials: JM
authors.lastname: Moreno
authors.forename: Kornelius
authors.initials: K
authors.lastname: Nielsch
authors.forename: Bernd
authors.initials: B
authors.lastname: Stühn
authors.forename: Christian
authors.initials: C
authors.lastname: Hess
authors.forename: Christina
authors.initials: C
authors.lastname: Trautmann
authors.forename: Maria E
authors.initials: ME
authors.lastname: Toimil-Molares