Preparation And Photocatalytic Performance Of Ordered Mesoporous Carbon Supported Tungsten Trioxide Composite

As an efficient,environmentally friendly,low-cost,and safe technology,photocatalytic technology has attracted more and more attention.The photocatalytic degradation can effectively degrade a variety of organic pollutants and mineralize them into CO₂,H₂O or less toxic organic matter.Mesoporous carbon material is a kind of mesoporous material with development potential,which has many advantages such as high specific surface area,adjustable pore structure,easy functionalization of the surface,and good conductivity.Therefore,it is used in many fields such as separation and adsorption,photocatalytic reaction,etc.The mesoporous carbon materials functionalized with tungsten trioxide（WO₃）are widely studied.WO₃ is a promising photocatalytic material as a transition metal oxide with a wide range of applications.In this paper,a series of ordered mesoporous carbon supported tungsten trioxide（WO₃/OMC）composite materials was designed and perpared,and photocatalytic degradation performance of the composite materials was studied through,photocatalytic degradation of organic pollutants.The content is as follows:（1）The post-synthesis strategy:firstly,highly ordered mesoporous silicon oxide（OMS）used as the hard template was synthesized using the triblock copolymer P123（PEO-PPO-PEO）as the template,orthosilicate bond（TEOS）as the inorganic silicon source,and hydrochloric acid as the medium.Secondly,sucrose was used as the carbon source.Ordered mesoporous carbon（OMC）was synthesized through secondary filling,high-temperature carbonization,and template removal.Finally,sodium tungstate was used as the tungsten source precursor.Small-angle X-ray powder diffraction,electron microscopy technology was used to characterize the morphology,structural order and pore structure of the composite material,and the composition and structure of the composite material were analyzed by infrared spectroscopy,Raman scattering spectrogram and wide-angle X-ray powder diffraction.The photocatalytic degradation activity of the composite material was investigated through the photocatalytic degradation of rhodamine B（Rh B）.Firstly,the impact of different catalysts on the degradation experiments were explored.Second,the effects of different factors such as the initial concentration of Rh B and the amount of p-OMCW-2 composites on the degradation activity were studied,and finally,the catalyst thermal stability performance was also examined.（2）Improved one-step synthesis strategy:firstly,the graphite-supported phosphotungstic acid composite（HPW/OMS）used as a hard template containing a tungsten source precursor was synthesized using the triblock copolymer P123 as the template,tertiary orthosilicate as the inorganic silicon source,and phosphotungstic acid（HPW）as the active site.Secondly,ordered mesoporous carbon-supported tungsten trioxide composite material（OMCW-x）were synthesized in one step using sucrose as a carbon source,through filling,high-temperature carbonization,and template removal techniques.The morphology,structural order and pore structure of the composite material were characterized by small-angle X-ray powder diffraction,electron microscopy analysis.And the composition and structure of the composite material were characterized by infrared spectroscopy,ultraviolet-visible diffuse reflectance spectroscopy,Raman scattering spectra and wide-angle X-ray powder diffraction to prove that the tungsten source precursor was successfully dated and transformed into the WO₃ active center body.Finally,the photocatalytic degradation activity of OMCW-x composites for degrading Rh B and phenol was investigated by the photocatalytic experimental.The effects of catalyst type,initial concentrations,catalyst dosage and p H on the photocatalytic degradation performance were investigated,as well as the thermal stability of the catalysts.