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Abstract: Sol–gel dip coated indium tin oxide film of In:Sn=90:10 was prepared on glass at 350°C from aqueous precursor. Nanostructured feature and cubic phase of the film were characterized by scanning electron microscopy and X-ray diffraction studies, respectively. Average cluster of 4.7nm diameter was measured by the transmission electron microscopy and it is near to Bohr radius of In2O3. The evaluated bandgap of the nanocluster (E g =4.0eV) is consistent with the absorption band appearing for quantum confinement. The confinement phenomenon resulted in photoluminescence (PL) when excited at different photoluminescence excitation wavelengths. The PL bands have been identified as the emissions of bound and free excitons. [Copyright &y& Elsevier]

The incorporation of Cu2+ in zirconyl chloride octahydrate sol or solution was used as a precursor for dip coating. This resulted in the in-situ formation of nanostructured Cu20 quantum particles in the zirconia matrix. The size-dependent properties of the Cu20 quantum particles were observed when the films were annealed in the range of 200-600 °C. A red shift of the UV band, ascribed to the transition from the copper d-shells to higher sublevels of the conduction band, was observed in the range of 260-315 nm due to an increase in the nanocrystallite size with increasing annealing temperature. Three types of emissions, blue, green, and yellow, were observed in films of relatively high thickness (around 120-130 nm) due to Wannier-bke excitonic transitions. For films of relatively low thickness (50-70 rim) only green emission was observed. From lifetime measurements of samples annealed at 450°C it may be concluded that the short decay time is bi-exponential in character from ns to ps with the chi-square value of 1.005, which is due to the confinement of Cu2O quantum panicles. [ABSTRACT FROM AUTHOR]