TiO₂:(Fe, S) Thin Films Prepared from Complex Precursors by CVD, Physical Chemical Properties, and Photocatalysis

Abstract

The TiO2thin films were prepared using Ti(dpm)2(OPri)2and Ti(OPri)4(dpm = 2,2,6,6-tetramethylheptane-3,5-dione,Pri= isopropyl) as the precursors. The volatile compounds Fe[(C2H5)2NCS2]3and [(CH3)C]2S2were used to prepare doped TiO2films. The synthesis was done in vacuum or in the presence of Ar and O2. The pressure in the CVD chamber was varied between1.2×10−4 mbar and 0.1 mbar, with the system working either in the molecular beam or gas flow regime. Physical, chemical, and photocatalytic properties of the (Fe, S)-doped TiO2films were studied. Those TiO2:(Fe, S) films prepared from the Ti(OPri)4precursor show increased photocatalytic activities, very close to those of Degussa P25 powder in UV region.

Photocatalytic Activity of Toluene under UV-LED Light with TiO2Thin Films

“…Thus, the Fe 3+ ions can enter into the crystal structure of titania and locate at interstices or replace some of the lattice sites of TiO 2 , forming an iron-titanium solid solution [26,27]. A similar finding was also reported previously in several studies, which prepared the thin films by the solgel, chemical vapor deposition (CVD) and electrophoretic deposition (EPD) techniques, and where the films were annealed at temperatures ranging from 400 to 600 • C [9,24,25,28].…”

“…(Figure 2). The strong peaks confirm the presence of only anatase phase in the TiO 2 thin films [23][24][25]. From the XRD pattern, increasing the Fe 3+ dopant concentration in TiO 2 thin films does not affect the phase of TiO 2 .…”

Processing of Nanostructured TiO2 and Modification of Its Photocatalytic Behavior for Methylene Blue Degradation

“…Diverse techniques such as sputtering [4], electrospinning [2], chemical vapor deposition [5][6][7] and sol-gel [8][9][10][11][12][13][14] can be used to produce a desirable TiO2 film. Among all these methods, sol-gel has been widely used due to its low cost, desirable homogeneity, and low processing temperature.…”

A Comparative Evaluation of TiO2Suspension Coating Techniques: A Novel Technique to Achieve Optimal Thickness and Uniformity of Photocatalytic Film

“…Photocatalysts are a group of nanoscale semiconductor materials that are able to generate free radicals after being stimulated by photons of light at certain wavelengths [1]. The free radicals that are generated cause the photocatalytic oxidation of surrounding materials [2,3].…”

“…When evaluating the photocatalytic performance of materials in removing compounds in the gas phase, it is necessary for the catalysts to be coated on a fixed [6][7][8] or mobilised bed [9,10]. Researchers have applied different techniques for coating the surfaces [1,11]. One of the simplest methods of coating uses a suspension that includes a prepared photocatalyst [11].…”