Effect of zirconium incorporation on the stabilization of TiO₂ mesoporous structure

Abstract

The effect of incorporating zirconium dioxide in TiO 2 mesoporous films was investigated. Improved stability of the mesoporous structure of the synthesized TiO 2 /ZrO 2 nanocomposites could be related to the suppression of titania crystallites growth and the formation of Ti 1−x Zr x O 2 solid solution, as was inferred by the results of optical properties, AFM, XRD and XPS investigations.

Zirconium doped TiO2 thin films deposited by chemical spray pyrolysis

“…These BE are slightly higher than those expected for pure TiO 2 [11]. The shift to higher BE indicates an increasing amount of Zr in substitutional sites of TiO 2 because of the higher electronegativity of Zr (1.6) compared to Ti (1.5) [1,11]. This corresponds to the shift in the diffraction angles of the anatase (101) peak to lower values (Fig 3(a) and Table 1) in the XRD results and hence confirming the incorporation of Zr in the TiO 2 lattice in substitutional mode.…”

“…4 for (a) TiO 2 :Zr (10) increased from 0 to 10 to 20 at%, the peak position of the Ti 2p 3/2 shifted to higher BE from 459.09 eV to 459.57 eV to 459.66 eV, respectively. These BE are slightly higher than those expected for pure TiO 2 [11]. The shift to higher BE indicates an increasing amount of Zr in substitutional sites of TiO 2 because of the higher electronegativity of Zr (1.6) compared to Ti (1.5) [1,11].…”

“…This is determined by the synthesis method, which in turn affects the locations and solubilities of Zr ions. For example, Ti 1-x Zr x O 2 solid solutions synthesized by citric acid complexing or inverse microemulsion Zr doping only takes place at the surface with solubility limit of ca 7.5 at% [11,24], while for sol-gel-derived solid solutions have different but higher solubilities [1,20]. Only large amounts of Zr ions doped in the bulk lattice of TiO 2 can cause change in the band gap and shift in the diffraction peaks [20].…”

“…TiO 2 has been continuously studied due to its potential for many applications such as photocatalysis, photovoltaics, water purification, thin film transistors etc. Introduction of Zr atoms as dopants into the TiO 2 matrix has been studied in the form of nanoparticles [1,2], powders [3][4][5][6][7][8][9] nanorods [10], mesoporous and nanocomposites films [11], and co-doping with other elements [7,8,12] by adding Zr source material into the TiO 2 [3,4].…”

“…Changes in their properties caused by doping usually depend on the synthesis method and conditions, the ratios of the components, nature of source materials and post-synthesis treatments. ZrO 2 -TiO 2 oxide mixtures and Ti x-1 Zr x O 2 solid solutions have been prepared by various methods including hydrothermal [10], ultrasonic spray pyrolysis [6], sol-gel [1,5,7,11], co-precipitation [8] citric acid complexing method [9], screen printing [13,14], RF magnetron sputtering [15], mechanical ball milling [16] and dip coating [17].…”