  Nanostructures of Titanium oxide (TiO2) are being studied for many promising
applications, e.g., solar photovoltaics, solar water splitting for H2 fuel
generation etc., due to their excellent photo-catalytic properties. We have
synthesized low-dimensional TiO2 nanoparticles by gas phase CW CO2 laser
pyrolysis. The laser synthesis process has been optimized for the deposition of
highly pure, nearly mono-dispersed TiO2 nanoparticles on silicon substrates.
Hard x-ray standing wave-field (XSW) measurements in total reflection geometry
were carried out on the BL-16 beamline of Indus-2 synchrotron radiation
facility in combination with x-ray reflectivity and grazing incidence x-ray
fluorescence measurements for the determination of surface morphology of the
deposited TiO2 nanostructures. The average particle size of TiO2 nanostructure
estimated using transmission electron microscopy (TEM) was found to closely
agree with the XSW and grazing incidence x-ray diffraction (GIXRD) results.
