Effect of Cobalt Doping on the Phase Transformation of TiO<SUB>2</SUB> Nanoparticles

Abstract

Co-doped TiO 2 nanoparticles containing 0.0085, 0.017, 0.0255, 0.034, and 0.085 mol % Co(III) ion dopant were synthesized via sol-gel and dip-coating techniques. The effects of metal ion doping on the transformation of anatase to the rutile phase have been investigated. Several analytical tools, such as X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray analysis (EDAX) were used to investigate the nanoparticle structure, size distribution, and composition. Results obtained revealed that the rutile to anatase concentration ratio increases with increase of the cobalt dopant concentration and annealing temperature. The typical composition of Co-doped TiO 2 was Ti 1−x Co x O 2 , where x values ranged from 0.0085 to 0.085. The activation energy for the phase transformation from anatase to rutile was measured to be 229, 222, 211, and 195 kJ/mole for 0.0085, 0.017, 0.0255, and 0.034 mol % Co in TiO 2 , respectively.

Synergistic Effects of Phosphorus and Cobalt Binary Doping on Visible Light Activity of TiO2 by Sol-Gel Method and Evaluation of Photocatalytic Efficiency

“…2d) of cobalt 2p3/2 and cobalt 2p1/2 peaks are located at binding energies of 782.52 eV and 801.448 eV respectively, which indicated that, a shift towards positive value due to phosphorus doping. These peaks confirms the presence of cobalt in TiO2 lattice as Co 2+ oxidation state as a substitutional dopant occupying the Ti 4+ site in TiO2 lattice [41,42]. From the Fig.…”

The effects of magnesium and aluminium ions’ additions on the kinetics of titanium dioxide structural transformation

“…4. The calculation of the mass fraction of rutile in the samples was based on the relationship [6,17].…”

“…In order to obtain titanium dioxide as rutile structure, the process of calcination of hydrate TiO 2 at the temperature about 950°C is employed. The presence of accompanying elements can exert influence on temperature as well as kinetics of the anatase-rutile transformation [1][2][3][4][5][6][7][8][9].…”

“…are responsible for the changes of temperatures of transformations (anataserutile) and thus can exert their influence on the rate of this transformation. Also, these substances have the essential influence on the physicochemical properties of the rutile phase [2][3][4][5][6][7][8][9].…”

Characterization and Humidity Sensing Application of WO3-SnO2 Nanocomposite

“…The electrical behaviour of electronic-type sensors in the presence of water vapor a reaction takes place between the oxygen ions adsorbed on the surface of the semiconductor and the water molecule. Many attempts have been made to enhance the sensitivity of semiconductor humidity sensors, one of which involved the doping is an attractive and effective tool for improved different properties of humidity sensors [12,13]. SnO 2 doped WO 3 alter various properties such as sensitivity, good reproducibility, exhibits different types of morphologies and have many applications.…”