Fabrication and characterization of Al-doped TiO2-CdS nanocomposite

Al-doped TiO2-CdS nanocomposite was prepared by introduction of 0.3%wt of Al3+ ions into the TiO2 paste and then CdS quantum dots were loaded on the Al-TiO2 film by the SILAR method. The Al-doped TiO2-CdS nanocomposite film was characterized by the SEM image, UV-visible and XPS spectra. It was found that a broad peak exists in the UV-visible spectrum in range of 370–500 nm which was due to the surface plasmon resonance of metal oxide/sulfide. It was found that the band gap of the nanocomposite was 2.36 eV falling within the visible region of the spectrum. The SEM image exhibited that when the Al3+ was doped into TiO2 film, the spherical particles were somewhat agglomerated to form larger particles which had diameters near 72 nm. The XPS spectrum revealed that the relative elemental percentages for the Al content in the composite was 0.297% which was very close to the experimentally used amount of 0.3%. This confirmed that the Al3+ ions were successfully doped within the TiO2/CdS film.

Keywords:

nanocomposite film , Al-doped TiO2-CdS , SEM , UV-visible spectrum , XPS spectrum