Processing-Induced Modification of Photo- and Cathodoluminescence Spectra of TiO2 Nanotubes

Abstract

Cathodoluminescence and photoluminecsence are investigated in titanium dioxide nanotubes (TiO2 NTs) produced in an ethylene glycol based electrolyte with the variation of the temperature of the electrolyte which allows the control of the inner diameter of nanotubes. The crystal structure of the produced nanotubes is controlled by the post-anodization thermal treatment. A new fast and cost-effective method for the fabrication of anatase TiO2 NTs is proposed. The cathodoluminescence spectra and panchromatic images from the produced TiO2 nanotubes suggest the formation of resonator modes in clusters of nanotubes. The enhancement of the ultraviolet near-bandgap or the green photoluminescence is demonstrated by means of coating the anatase TiO2 nanotubes with thin Ag or Au films, respectively.