Influence of rhodamine 6G doping on the optical properties of TiO2 sol-gel films

Abstract

Amorphous titanium dioxide ͑TiO 2 ͒ thin films doped with rhodamine 6G ͑R6G͒ were deposited on glass substrates by the sol-gel process. The optical properties of the films were characterized by photoacoustic, excitation, and fluorescence spectroscopies. The absorption spectra of the R6G-doped TiO 2 films exhibited two well-defined absorption regions: an absorption band over 2.0 eV attributed to rhodamine 6G and a band above 3.0 eV corresponding to TiO 2 absorption. While the onset of the R6G absorption band was shifted by 0.06 eV towards lower energies as the R6G doping concentration increased within the interval of 0.01-0.10 mol %, the onset to high absorption ͑TiO 2 band͒ for the doped films decreased only by 0.01 eV within the same interval. In addition, the optical absorption of undoped rutile-phase bulk TiO 2 was calculated and compared to the experimental results. The estimated theoretical value of rutile TiO 2 sample was 3.0 eV. This theoretical result shows good agreement when compared with the experimental data of undoped TiO 2 sol-gel films, as well as the undoped TiO 2 film prepared by sputtering.

Molecular dynamics simulation of the effect of pH on the adsorption of rhodamine laser dyes on TiO2hydroxylated surfaces

“…The evaporation was carried out by placing the substrates at a glancing angle of 70º with respect to the evaporator source. This geometry produces films with a tilted columnar microstructure and a high porosity [19][20][21] . Thin films with a thickness around 400 nm were prepared by this method.…”

Photoluminescence properties of the ZnO–CdO–TeO2 system doped with the Tb3+and Yb3+ ions

“…2 illustrates a (PAS) 2 versus hn typical plot for the E g calculation. PA has been successfully used to measure E g in other type of materials [16][17][18]. It can be observed how the E g value is limited to take values in the interval 3.47-3.60 eV, which seems to be in agreement with E g ¼ 3.9 eV of CdTeO 3 [10,15].…”

A Full Vacuum Approach for the Fabrication of Hybrid White‐Light‐Emitting Thin Films and Wide‐Range In Situ Tunable Luminescent Microcavities

“…This type of films offers unique host possibilities for the incorporation of active molecules, metal nanoparticles, or quantum dots for the fabrication of photonic gas sensors, information encoding or biodetectors . In most of these applications the incorporation of the photonic or functional active component(s) requires the intervention of wet chemical processes . In contrast, the present work aims primarily at developing a “dry” evaporation‐based procedure for the incorporation of several organic dye molecules into the pores of inorganic host thin films.…”