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چکیده
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Heterostructured photocatalysts based on TiO2 and perovskite oxides were synthesized by a simple hydrothermal method and the prepared particles were annealed at 600C.[1]. The TiO2/PbTiO3 nanocomposites are a group of semiconductor materials that have been widely used in photocatalytic fields due to their suitable band gap and easy synthesis methods. The heterojunction structures can promote charge separation through favorable band alignments, leading to the reduction of recombination [2], [3]. Successful composite grafting was confirmed by Fourier transform infrared spectroscopy (FTIR), UV-Vis-NIR spectrophotometer, photoluminescence (PL) spectra, field emission scanning electron microscope (FE-SEM) with energy-dispersive X-ray spectroscopy (EDS). The photocatalytic activity of heterostructured TiO2/PbTiO3 perovskite nanoparticles is utilized for the photocatalytic degradation of methylene blue under UV light (8 Watts Philips UV lamp) irradiation. The TiO2/PbTiO3 nanocomposite displayed high photocatalytic activity in the degradation of methylene blue, higher than that of pure PbTiO3 under UV light. This high photocatalytic degradation yield may emanate from the effective separation of electron-hole pairs between PbTiO3 and TiO2. The low peak intensity of the photoluminescence (PL) spectra of the TiO2/PbTiO3 nanocomposite indicates that a suitable charge separation has been performed by the photocatalyst, which is desirable for the photocatalytic process. The trapping experiments confirm the role of hydroxyl radical (˚OH) in the proposed mechanism. The synthesized photo-catalyst is reusable under several cyclic tests. Thus, TiO2/PbTiO3 nanocomposites had a certain application value in the field of wastewater treatment
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