Synthesis and Photoluminescence Properties of SnO2 Nanopowder

SnO2 nanopowder was synthesized by calcining metastannic salt (SnO2 center dot H2O) prepared by chemically etching metallic Sn in aqueous HNO3 solution. The calcined SnO2 nanopowder was investigated by X-ray diffraction (XRD) measurement and photoluminescence (PL) spectroscopy. The XRD and PL intensities increased with increasing calcining temperature, yielding an activation energy of similar to 0.65 eV. The PL spectra of the calcined SnO2 nanopowder exhibited green (G) and red (R) emission bands with peaks at similar to 2.5 and similar to 2.0 eV, respectively, that were clearly dependent not only on the excitation light wavelength but also on the sample temperature. The temperature dependence of the PL intensity between 20 and 300 K was explained by the thermal quenching with activation energies of similar to 15meV (T = 20-60 K) and similar to 0.12-0.18 eV (T >= 100 K). The G and R emission states were found to originate from the Jahn-Teller effect of the 5s(2) (Sn-2) ions in the SnO2 matrix and were similar to those generally observed in many ns(2)-doped alkali halides and SnCl2. (C) 2012 The Japan Society of Applied Physics