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Abstract: Sol–gel based nanostructured Cr(III)-doped indium tin oxide (ITO) films (In:Sn:Cr=84.6:9.4:6.0) deposited on silica glass were cured at 350°C, 450°C, 600°C, 700°C and 900°C. EDX, absorption spectra and TEM images confirmed formation of Cr(III)-doped ITO nanoclusters close to Bohr radius of ITO. Excitonic and phonon interactions were studied by absorption, photoluminescence (PL) and Raman spectra. The photon energy between the satellite peaks of PL spectra predicted phonon vibrations. Strong hybridization between s–p-states of host and d-states of Cr(III) resulted in stable exciton–phonon coupling as revealed from excitonic and lattice phonon vibrations. Soft room temperature ferromagnetism was observed in the films. [Copyright &y& Elsevier]

Abstract: Nanostructured indium tin oxide (ITO) films were deposited on silica glass by sol–gel dipping method from salt derived PVA based aqueous precursor. The films were cured at 250°C, 350°C, 450°C, 600°C, 700°C and 900°C and characterized by XRD, SEM, AFM techniques to observe heating effect on nanostructured feature. Nanocluster sizes were determined by TEM study. Different crystal phases of ITO were existed in the temperature range 250–900°C. Quantum confinement behavior of the nanoclusters was observed for their size being near Bohr radius. Absorption, band gap and photoluminescence behavior of the nanstructured ITO films supported excitonic transitions due to the formation of electron hole pair generated by interaction of electromagnetic radiation. [Copyright &y& Elsevier]

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]