Blue shift of Raman peak from coated TiO₂ nanoparticles

Abstract

Nanosized TiO 2 particles coated with dodecylbenzenesulfonic acid (DBS) and stearic acid (St) were prepared using the hydrothermal procedure. The average size of the DBS/TiO 2 and St/TiO 2 particles is very small, about 8 nm. Raman spectra from DBS/TiO 2 and St/TiO 2 were measured, and scattering signals from both TiO 2 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.

Annealing Temperature Effect on the Physical Properties of Titanium Oxide Thin Films Prepared by the Sol-Gel Method

“…The spectra also exhibit three main phonon modes, B1g, Eg, and Ag, which appear at 140, 433, and 617 cm -1 , respectively. This result confirms the presence of a rutile phase TiO 2 [26,27]. The B2g mode of rutile TiO 2 centered at 822 cm -1 appears clearly after annealing at 800°C, which shows that the rutile phase becomes gradually the dominant phase starting at 800°C, indicating that the anatase-rutile transition temperature should be less than 800°C.…”

Erratum: Fabrication of Ca, Zr doped BaTiO3 ferroelectric nanofibers by electrospinning

“…Comparing Raman spectra of nanofibers and bulk BCTZ, we found Raman peaks at 518 and 718 cm -1 for bulk ceramics shift, respectively, to 523 and 724 cm -1 in nanofibers. This could be a result of crystallite size reduction that has been earlier observed in many nanosize oxides synthesized by various techniques [15].…”

Nanophosphors with Partially Polymerized SiO<sub>4</sub> Tetrahedra Produced by Evaporation of Ca<sub>2</sub>Y<sub>8</sub> (SiO<sub>4</sub>)<sub>6</sub>O<sub>2</sub>: Eu Polycrystals

“…The unification of vacancies leads to translation symmetry breakdown. Such symmetry breakdown can be also the cause of line strength reduction at ν 1 [15,16].…”