Dr. Munirah Ghunaim presented a lecture on Tuesday, 15/7/1438, at 9:30 AM,  Hall No 1C-225 at the college of Science. The lecture was attended by some faculty and students.  Their participation has had the greatest impact on effective learning enriching the debate on nanotechnology and its effectiveness.

Lecture title and summary:

Microwave Assisted Synthesis of Pure Anatase  TiO2,  Ag/TiO2  and Ag/TiO2/GO

Nanocomposites and their Photocatalytic Activities

T.  Bora, E.  H.  Alsharaeh, A.  Soliman, M.  G.  Ghoniem, K.  M.  Abu-Salah and J.  Duttae

A simple microwave assisted wet chemical route to synthesize pure anatase phase titanium dioxide (TiO2) nanoparticles is reported here using titanium tetrachloride (TiCl4) as initial interaction material.  The as-prepared TiO2 nanoparticles are characterized by electron microscopy, X-ray diffraction, UV/visible absorption, infrared and Raman spectroscopic techniques. Further modification of the anatase TiO2 nanoparticles is carried out by incorporating plasmonic silver (Ag) nanoparticles and graphene oxide (GO) in order to improve the visible light absorption. Photocatalytic activities of the anatase TiO2, Ag/TiO2 and Ag/TiO2/GO nanocomposites are evaluated under both ultraviolet (UV) and visible light irradiation using phenol as a model contaminant. The presence of Ag nanoparticles is found to play a significant role defining the photocatalytic activity of the Ag/TiO2/GO nanocomposite. It is found that Ag acts like sink under UV excitation and store photo-generated electrons from TiO2. while under visible light excitation they act as photosensitizers enhancing the photocatalytic activity of the nanocomposite. The role of Ag nanoparticles and GO on the photo-generated charge transfer mechanism and therefore its effect on the photocatalytic activity of the Ag/TiO2/GO system is probed and discussed under both UV and visible light excitation.

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