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Double-walled iron oxide nanotubes via selective chemical etching and Kirkendall process.

ABSTRACT: Double-walled oxide nanotube structures are interesting for a wide range of applications, from photocatalysis to drug delivery. In this work, a progressive oxidation method to fabricate double-walled nanotube structures is reported in detail. The approach is based on the electrodeposition of metallic iron nanowires, in porous alumina templates, followed by a selective chemical etching, nanoscale Kirkendall effect, a fast oxidation and out-diffusion of the metallic core structure during thermal annealing. To validate the formation mechanism of such core-shell structure, chemical composition and atomic structure were assessed. The resulting hematite nanotubes have a high degree of uniformity, along several microns, and a nanoscopic double-walled structure.

SUBMITTER: Azevedo J

PROVIDER: S-EPMC6700129 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Double-walled iron oxide nanotubes via selective chemical etching and Kirkendall process.

Azevedo João J Fernández-García M P MP Magén César C Mendes Adélio A Araújo João P JP Sousa Célia T CT

Scientific reports 20190819 1

Double-walled oxide nanotube structures are interesting for a wide range of applications, from photocatalysis to drug delivery. In this work, a progressive oxidation method to fabricate double-walled nanotube structures is reported in detail. The approach is based on the electrodeposition of metallic iron nanowires, in porous alumina templates, followed by a selective chemical etching, nanoscale Kirkendall effect, a fast oxidation and out-diffusion of the metallic core structure during thermal a ...[more]

PMID: 31427675

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