Effect of the RE (RE=Eu, Er) doping on the structural and textural properties of mesoporous TiO2 thin films obtained by evaporation induced self-assembly method

Towards the design of bioceramics with control over both macroscopic shape and mesoporosity, silica based mesoporous materials have been synthesized using evaporation-induced self-assembly method by two different routes: room temperature (RT) and aerosol-assisted synthesis (A-A). Two series varying surfactant/silica precursor ratio have been synthesized in order to check the mesopore ordering as a function of the structure directing agent amount in both preparation procedures. The A-A method leads to spherical microparticles, which exhibit mesopore ordering for a wider surfactant/silica range compared with room temperature method, which yield irregular shaped particles. Textural properties values show that for the same surfactant amount, aerosol-assisted method develops higher porosity values in the obtained silica microparticles.

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Efficient removal of 2-chlorophenol from aqueous solution using TiO2 thin films/alumina disc as photocatalyst by pulsed laser deposition

Applied Water Science ◽

10.1007/s13201-021-01372-x ◽

2021 ◽

Vol 11 (2) ◽

Author(s):

S. Ismat Shah ◽

Sawsan A. Mahmoud ◽

Samar H. Bendary ◽

Ahmed K. Aboulgheit ◽

A. A. Salem ◽

...

Keyword(s):

Thin Films ◽

Photocatalytic Degradation ◽

Pulsed Laser Deposition ◽

Catalyst Surface ◽

Irradiation Time ◽

Pulsed Laser ◽

Textural Properties ◽

Laser Deposition ◽

Hydroxyl Groups ◽

Tio2 Thin Films

AbstractPulsed laser deposition facilitates the epitaxial deposition and growth of TiO2 at low temperature on hot substrate. In this study, nanosized nitrogen-doped TiO2 thin films were deposited on fabricated alumina disc-shaped and glass substrates. Textural properties of the fabricated disc and alumina disc-supported TiO2 were investigated using N2 adsorption–desorption isotherms, field emission scanning electron microscopy (FESEM), X-ray diffraction and Fourier transform infrared (FTIR) spectroscopy. FESEM showed the presence of single crystals of TiO2 on the alumina disc. FTIR showed the presence of octahedral TiO2 and different hydroxyl groups on the surface which is responsible for the photoactivity and also showed the functional groups adsorbed on the catalyst surface after the photocatalytic degradation. The concentration of 2-chlorophenol and the photo-redox intermediate products as a function of irradiation time was determined. The concentration of the produced chloride ion during the photocatalytic degradation was determined by an ion chromatography. The results showed that the photocatalytic activity of the catalyst decreased upon cycling. The obtained results were compared with nanostructured TiO2 supported on glass substrate. Higher efficiency of 100% degradation was achieved for TiO2/Al2O3 catalyst, whereas about 70% degradation of 2-CP was achieved using TiO2/glass. Different photointermediates of 2-CP degradation have been identified for each cycle. The difference of intermediates is supported by the adsorbed fragments on the catalyst surface.

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