| In this paper,Bi4 Ti3O12 nanoparticles is prepared by using the polyacrylamide gel method.Our research is focused on the preparation and p hotocatalytic performance of Bi4 Ti3O12 nanoparticles,g-C3N4@Bi4Ti3O12 and Ag@Bi4 Ti3O12 nanocomposites.The main research results are as follows:?1?The polyacrylamide gel route is introduced to prepare different sizes of Bi4 Ti3O12nanoparticles by utilizing various chelating agent.Prepared samples are characterized by techniques such as X-ray diffraction?XRD?,scanning electron microscope?SEM?and ultraviolet-visible diffuse reflectance spectroscopy?DRS?.The influence of p H value on the absorption and photocatalytic degradation of dye is also investigated by adjusting p H value.The significant effect of p H value on dye adsorption can be explained by the change of p H-induced surface charge of Bi4 Ti3O12 particles,resulting in the alterations of dye absorption and photocatalytic activity.Simultaneously,the control experiment,with addition of scavenger for·OH,·O2-and h+radical species,is carried out to further understand the nature of primary active species involved in visible light degradation of Rh B over Bi4 Ti3O12nanoparticle.?2?The Bi4Ti3O12 nanoparticles,prepared by polyacrylamide gel route with the use of citric acid as chelating agent,combined with g-C3N4 nanoplate and nanoparticles.Prepared samples are characterized by XRD,SEM,field-emission transmission electron microscope?TEM?and X-ray photoelectron spectroscopy?XPS?.The result shows that p-n heterostructure is formed successfully via the Bi4 Ti3O12 nanoparticles compounded with two different morphologies of g-C3N4 method.The photocatalytic activity of composites are systematically investigated,and the result shows that g-C3N4@Bi4Ti3O12 composites exhibit an obviously enhanced photocatalytic activity compared to bare Bi4 Ti3O12.In order to clarify the role of active species in the photocatalysis,the effects of introducing AO?h+scavenger?,ethanol?·OH scavenger?,BQ?·O2-scavenger?are investigated.At the same time,to reveal thephotocatalysismechanism,weexaminethe·OHformedover simulated-sunlight-irradiated photocatalyst by spectrofluorimetry using TPA as the·OH scavenger.?3?Light reduction method has been used to prepare Ag@Bi4 Ti3O12 composites.The samples are characterized by XRD,TEM and PL.Research results show that Ag particles is successfully deposited on the surface of Bi4 Ti3O12 nanoparticles.The samples'photocatalytic actvity is evaluated by degrading Rh B under simulated-sunlight irradiation.Compared to bare Bi4Ti3O12 nanoparticles,the photocatalytic activity of Ag@Bi4 Ti3O12 exhibits an obvious augment.This can be explained by the effective separation of e--h+pairs to increase the availability of carriers for photocatalytic reaction,in which case e-transfers from Bi4Ti3O12 to Ag nanoparticles.Besides,holes are suggested to be the main active species responsible for the dye degradation based on experiment result. |
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