This document summarizes a study on the synthesis and characterization of titanium dioxide (TiO2) hollow nanostructures using a low-temperature hydrothermal route. Three hydrothermal methods were used to develop TiO2 nanotubular structures using rutile mineral powder as a starting material. Characterization with XRD, SEM and EDS showed that the fabricated TiO2 nanotubes had diameters ranging from 65-400 nm and lengths up to microns. The hydrothermal synthesis method allows control over the nanostructure morphology and is suitable for scaling up production of TiO2 nanotubes for applications in photoactive devices, sensors, and energy storage.

1. Synthesis,Characterization& Applications of TiO2
HollowNanostructuresby HydrothermalRoutefor
Commercial Scale Up.
A. Ikram1, S. Jilani1, F.A. Khalid1, A. Shehzad2
1Faculty of Materials Science & Engineering, Ghulam Ishaq Khan Institute of Engineering Science & Technology, Topi, KPK, Pakistan, (23404).
2Center for Micro & Nano Devices, Department of Physics, COMSAT Institute of Information & Technology, Islamabad, Pakistan (45000).
Abstract
This study presents simple route to synthesize Titanium Dioxide Nanotubes (TNT) using Low Temperature Alkaline
Leaching (Hydrothermal), which is easily reproducible. We have used three different hydrothermal methods to
develop Nanotubular structures of Titania utilizing Powdered Nano Rutile Mineral (APS 50 nm) which has been
reported much less in similar studies previously. Characterization was accomplished with tools include XRD, SEM
and EDS. Length of tubes grown can continue in micrometer range with tunable diameters through Hydrother mal
Processing.Diameter of our fabricated TNTs was observed in nanoscalerange(65-200 nm for discontinuous TNTs at
nucleation sites while 200-400 nm for individual continuous nanotubes), for which lengths continue in order of
hundreds of nanometers to few microns (>1000 nmon average). Controllingprocessingparameters can help develop
range of different nanostructures likenanotubes, nanowires,nanorods,nanoribbons etc. with same hydrothermal
approach. The method is good to scale up multiwall Titania Nanotubes for commercial applications in photoactive
devices, photosensors, gas sensors and storage devices (H2, O2) and dye sensitized solar cells.
Introduction
After discovery of Carbon derived nanotubes,research work was initiated on several inorganic nanotubes,like,Al2O3,
TiO2, V2O5, BN, GaN, CdS, ZnS, CdSe, MoS2 etc. Yet details on well-defined complex nanostructure are yet to be
revealed in true sense. Titaniumdioxide(TiO2) was initially soughtfor commercial applicationsin late20th Century
for application in Paints,Toothpastes,Pigments,Dyes and Biomaterial etc.More recently Titania Nanomaterialsfind
their applications potential in Dye Sensitized Solar Cells, Photoactive Devices, Battery Electrodes, Photocatalysis,
Hydrogen Storage & Sensors, Bioactivity & Biocompatibility etc. Hollow nanostructures which have high surface
areas,lowdensities and scalableelectronic/magnetic properties;areconsidered arerevolutionary breakthroughs in
materials which would eventually substitute for microscaleelectronics,solarcells,energy and data storage devices.
TitaniumDioxideTiO2 Nanotubes (TNTs) are among truly promisingnanostructures for application aswidegap
semiconductor oxide. Like Silica,Titaniaisrelatively inexpensive,thermally/chemically stable,mechanically robust
and UV excitable.Ithas been verified by experimentation that under UV Light, photocatalytic splittingof water is
possibleatTiO2 electrode. Lim et al.[1] found that TiO2 nanotubes could store ~ 2 wt. % H2 at room temperature
and 6 MPa pressure(losingabout75% storagecapacity atambient pressurewhile complete desorption was
possiblewith temperatures over 150 0C in vacuum); this adsorption characteristic of TNTs is much