Blue shift of Raman peak from coated TiO2 nanoparticles

Nanosized TiO2 particles coated with dodecylbenzenesulfonic acid (DBS) and stearic acid (St) were prepared using the hydrothermal procedure. The average size of the DBS/TiO2 and St/TiO2 particles is very small, about 8 nm. Raman spectra from DBS/TiO2 and St/TiO2 were measured, and scattering signals from both TiO2 and the coating were observed. It was found that in contrast to the red shift of Raman peaks in the nanoparticles with decrease in particle size, a blue shift, namely the Raman peak shift to the higher wavenumber side, in the coated particles was recorded. It was also found that different coatings show different extents of Raman shifts. The possible origin of the blue shift is discussed. Copyright © 2001 John Wiley & Sons, Ltd.

[1]  Zuhong Lu,et al.  Investigation of structural transformations in nanophase titanium dioxide by Raman spectroscopy , 1998 .

[2]  J. S. Lees,et al.  A structural investigation of titanium dioxide photocatalysts , 1991 .

[3]  N. Serpone,et al.  Photocatalysis: Fundamentals and Applications , 1989 .

[4]  Richard M. Martin,et al.  Light scattering study of boron nitride microcrystals , 1981 .

[5]  M. Schiavello.  Photoelectrochemistry, Photocatalysis and Photoreactors , 1985 .

[6]  Ming Zhang,et al.  Raman scattering by nanophase titanium dioxide , 1995 .

[7]  J. Scott,et al.  Raman scattering from surface modes of small CdS crystallites , 1972 .

[8]  S. Hayashi,et al.  Raman scattering from the surface phonon mode in GaP microcrystals , 1982 .

[9]  W. S. Li,et al.  Raman spectra of CuO nanocrystals , 1999 .

[10]  P. M. Amirtharaj,et al.  Effects of As+ ion implantation on the Raman spectra of GaAs: ‘‘Spatial correlation’’ interpretation , 1984 .

[11]  S. Matsuda,et al.  Titanium oxide based catalysts - a review , 1983 .

[12]  L. Kavan,et al.  Preparation of TiO2 (anatase) films on electrodes by anodic oxidative hydrolysis of TiCl3 , 1993 .

[13]  Philippe M. Fauchet,et al.  The effects of microcrystal size and shape on the one phonon Raman spectra of crystalline semiconductors , 1986 .

[14]  P. P. Lottici,et al.  Phonon confinement effects in the Raman scattering by TiO2 nanocrystals , 1998 .

[15]  R. Siegel,et al.  Raman spectroscopy of nanophase TiO_2 , 1989 .

[16]  R. Siegel,et al.  Calibration of the Raman spectrum to the oxygen stoichiometry of nanophase TiO2 , 1990 .

[17]  Arai,et al.  Raman scattering from CdSe microcrystals embedded in a germanate glass matrix. , 1992, Physical review. B, Condensed matter.

[18]  M. Kitajima,et al.  Infrared and Raman spectra of solid solutions Ti1-xZrxO2 (x≤0.1) , 1994 .

[19]  Shiv k. Sharma,et al.  Raman study of rutile (TiO2) at high pressures , 1980 .

[20]  H. Shen,et al.  Raman study of polish‐induced surface strain in 〈100〉 GaAs and InP , 1984 .

[21]  G. Zou,et al.  Raman study of anatase (TiO2) at high pressure , 1989 .

[22]  R. Tsu,et al.  Raman, transmission electron microscopy, and conductivity measurements in molecular beam deposited microcrystalline Si and Ge: A comparative study , 1985 .

[23]  K. Kobayakawa,et al.  Influence of the Density of Surface Hydroxyl Groups on TiO2 Photocatalytic Activities , 1990 .

[24]  R. Hempelmann,et al.  Inelastic light scattering and phonon‐confinement in nanocrystalline Y2O3 , 1997 .

[25]  W. Plieth,et al.  Raman spectroscopy of titanium dioxide layers , 1989 .

[26]  M. Schiavello.  Photocatalysis and Environment , 1988 .

[27]  J. Merz,et al.  Laterally injected low-threshold lasers by impurity-induced disordering , 1991 .

[28]  H. Harada,et al.  Photocatalytic activity of ultra-fine rutile in methanol-water solution and dependence of activity on particle size , 1984 .