title: In situ X-ray nanotomography of metal surfaces during electropolishing.
abstract: A low voltage electropolishing of metal wires is attractive for nanotechnology because it provides centimeter long and micrometer thick probes with the tip radius of tens of nanometers. Using X-ray nanotomography we studied morphological transformations of the surface of tungsten wires in a specially designed electrochemical cell where the wire is vertically submersed into the KOH electrolyte. It is shown that stability and uniformity of the probe span is supported by a porous shell growing at the surface of tungsten oxide and shielding the wire surface from flowing electrolyte. It is discovered that the kinetics of shell growth at the triple line, where meniscus meets the wire, is very different from that of the bulk of electrolyte. Many metals follow similar electrochemical transformations hence the discovered morphological transformations of metal surfaces are expected to play significant role in many natural and technological applications.
authors.affiliation: Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA.
authors.forename: Maryana I
authors.initials: MI
authors.lastname: Nave
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
authors.forename: Jason P
authors.initials: JP
authors.lastname: Allen
authors.affiliation: Photon Sciences Directorate, Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Karen Chen-Wiegart
authors.affiliation: Photon Sciences Directorate, Brookhaven National Laboratory, Upton, NY 11973, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
authors.forename: Surya R
authors.initials: SR
authors.lastname: Kalidindi
authors.affiliation: Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USA.
authors.forename: Konstantin G
authors.initials: KG
authors.lastname: Kornev