Preparation And Catalytic Performance Of Al₂O_3f/SiC_w Fibrous Porous Ceramics Modified By TiO₂ Nanosheets

With the increasingly serious global environmental problems and the increasing demand for energy,developing green environmental protection concepts,reducing the sources of various pollutants,and using hydrogen energy reasonably,reducing the dependence on traditional fossil fuel energy are the problems we meet.Therefore,it is particularly important to design and develop a kind of catalyst support material that can effectively mass photocatalysts and noble metal catalysts.Inorganic fiber materials can be widely used in the preparation of catalyst carrier materials due to their high specific surface area and stability performance in extreme environments,while two-dimensional materials have extremely high reaction contact areas,that are widely used in catalysts and catalyst carriers.High specific surface area has a good effect,whether as reaction contact area or catalyst support area.As a catalyst carrier,it not only provides a wide range of active attachment sites for the catalyst,but also makes the dispersion of the catalyst more uniform,further refining the size of nanocrystals,and improving the catalytic efficiency.The traditional supported photocatalysts are mainly loaded by coated and suspended method,which has the problem of low utilization rate.In order to solve the problems of the tranditional loaded methed,the thesis is mainly to use inorganic fiber as a raw material to obtain a kind of fibrous porous ceramic modified by TiO₂ nanosheets by using ethanol-thermal method,and make a research on the properties and performance of monolithic fibrous porous ceramic photocatalyst material loaded with TiO₂ nanosheets and TiO₂ nanosheets as catalyst carriers to loaded noble metal nanoparticles.It has potential value in the fields of photocatalytic degradation of pollutants,splitting water to produce hydrogen,as electrocatalyst to hydrogen evolution from water,and treatment of reducing pollution gas.To provides new a strategy for environmental protection,energy and other fields.In this thesis,Al₂O₃/SiC_w fibrous porous ceramics modified with TiO₂ nanosheets were successfully prepared.The morphology of TiO₂ photocatalyst loaded on the fiber surface by different additive content of tetrabutyl titanate and the effect of the proportion of fiber components on the photodegradation of Rhodamine B and the production of hydrogen by water splitting were studied The fibrous porous ceramic photocatalyst material of 50%SiC_w,could be completely degraded the rhodamine B solution with a concentration of 0.5 mg/L in 40 minutes,and the hydrogen production rate of photocatalytic was 0.34 mmol/h.The thesis regard the Al₂O_3f/SiC_w/TiO₂ fibrous porous ceramics as the noble catalyst supports to make a research of the effects of nanofiber addition and lamellar modification on the specific surface area and pore size distribution of fibrous porous ceramics.The effect of nanosheets structure on the loading mode of catalyst was studied,fibrous porous ceramic loaded Pt nano-particles was obtained.The effects of silicon carbide content,impregnating solution concentration and heat treatment temperature on the HER properties of Pt nanoparticles loaded on fibrous porous ceramics were investigated.The Al₂O_3f/SiC_w/TiO₂ fibrous porous ceramics loaded Pt-Pd nanoparticle catalyst material with a light-off temperature of less than 160°C and hydrogen conversion rate of up to 75%at temperature of more than 200?was obtained.