Study On The Design Of Novel Photonic Crystal Composites Material And Its Photocatalytic Properties

In recent years,semiconductor photocatalysis has attracted much attention for its potential application in environmental governance and new energy.Traditional photocatalyst has the disadvantages of low solar energy utilization rate and quantum efficiency,which restricts its development in its related field.Thus,designing new photocatalyst that has high solar energy utilization rate and quantum efficiency has become a hot research field of photocatalysis.Since photonic crystals has special structures and photon effect,it becomes more and more popular in the photocatalysis field.In this paper,we designed three novel photonic crystals(PCs)composites based on TiO2,which including Ag/TiO2 PCs,Ag/AgBr/TiO2 PCs and SiC@TiO2 PCs.The three materials were characterized by using XRD,DRS,SEM and XPS measurements.By degrading Rhodamine B under the illumination of simulated solar light,the activities and stability of the three photon crystal composites were investigated deeply and the factors that affect their photocatalytic properties were studied.According to the experimental results,a possible mechanism for the materials in photocatalytic degrading RhB was proposed.The main conclusions obtained from the article are as follows:(1)TiO2 PCs was successfully prepared by using an auto-forced impregnation method.(2)On the basis of TiO2 PCs,Ag/TiO2 PCs was synthesized via the impregnation method.When the photonic band gaps were matched with the localized surface plasmon resonance absorption peak of Ag,slow photonic effects and multiple scattering effects of photonic crystals could facilitate the localized surface plasmon resonance absorption of Ag.Compared to TiO2 PCs,photocatalytic activity of Ag/TiO2 PCs which exhibited optimal photocatalytic activity had been improved 1.78 times.(3)On the basis of TiO2 PCs,Ag/AgBr/TiO2 PCs was prepared by using the electrostatic-assembly method and the photo-reduction method.By designing a proper location of photonic band gap that could amplify the plasmon resonance absorption of Ag and the intrinsic excitation of AgBr simultaneously,the photocatalytic activity of Ag/AgBr/TiO2 PCs has been improved 2.29 times compared to TiO2 PCs.(4)SiC was wrapped in the skeleton of TiO2 photonic crystal by using mixed filling method,the mechanical strength and photocatalytic activity of the SiC@TiO2 PCs have been developed 3 times and 2.29 times respectively.The innovation obtained from the article are as follows:(1)Start from the effective regulation of the interaction between photons and electrons,the properties of photonic crystals enlarges surface plasmon resonance effect and the intrinsic semiconductor excitation skillfully,which has important theoretical and practical significance for photonic crystals applications in photocatalysis.(2)Learn from the'cement gravel road' model in macroscopic life,the SiC@TiO2 PCs are introduced into the TiO2 PCs system,which provides a new idea to improve the mechanical strength of the film material.