Studies On The Hydrothermal Synthesis And Photocatalytic Property Of Bismuth Titanate Nanomaterials

In this paper, the nano-materials of bismuth titanate(BTO), Bi FeO3 and Bi6Ti3Fe2O16 were successfully prepared by hydrothermal method under different conditions. Bi6Ti3Fe2O16-Bi OCl nano-composite-material was prepared by an ion replacement method. The structures and photocatalytic activity of these compounds were studied by X-ray diffraction(XRD), UV-Visible absorption spectrum, scanning electron microscopy(SEM), transmission electron microscopy(TEM) and photocatalytic degradation of Rhodamine B.BTO nanobelts were prepared by hydrothermal method. The effects of hydrothermal conditions, i.e. reaction temperature、pH value and reaction time, on the morphology, structure and photocatalytic activity of BTO nanobelts which are new crystal structure were systematically investigated. The possible crystal structure and composition of prepared BTO nanobelts were determined by powder X-ray diffraction, transmission electron microscopy and thermal analysis. The bandgap structure of BTO nanobelts were analyzed by using UV-Visible absorption spectrum to measure the forbidden band gap and X-ray photoelectron spectroscopy to determine the top edge of valence band of BTO nanobelts. The photocatalytic performance of the BTO nanobelts under visible light irradiation(λ>390 nm) and simulated sunlight irradiation were studied. The highest photocatalytic activity was observed in the BTO nanobelts hydrothermally grown for 48 h at 200 ℃ and pH = 13. Up to 95.0% rhodalnine B was decolorized after irradiation for 150 min under simulated sunlight, indicating good photocatalytic activity.BiFeO3 agglomerates composed of nanoparticles were prepared by the hydrothermal process. The nanomaterial exhibited a certain photocatalytic activity as evidenced by photodegradating of rhodalnine B under simulated sunlight.Bi6Ti3Fe2O18 nanoplates were grown by the hydrothermal method. The optimal process for the growth of nanoplates was studied by changing the reaction time and pH values. However, these nanoplates showed weak photocatalytic activity.Bi6Ti3Fe2O18-Bi OCl nano-composite-materials were synthesized by using reaction between HCl and Bi6Ti3Fe2O18. The reaction lasted 2h, 3h and 4h, respectively. The Bi6Ti3Fe2O18-Bi OCl nano-materials reacted for 4h displayed the highest photocatalytic activity. The nano-materials also exhibited good photocatalytic activity under visible light irradiation(λ>390 nm).