| To seek an effective indoor air purification technology, the developed environmental protection purification materials, improving indoor air quality, is an important and significative research subject.In recent years, photocatalytic oxidation technology, as a kind of extremely potential means of purification, can effective remove gaseous pollutants, thus more and more people get involved in the industry.But as a result of various volatile pollutants in indoor air, and low concentration, photocatalytic oxidation technology directly applied to indoor air pollutants degradation not only slower degradation, but also generate a lot of harmful by-product.So the photocatalytic oxidation technology is not suitable for direct application in indoor air purification.Mesoporous silica adsorption organic volatile pollutants of indoor air, not only can Ti O2 photocatalyst be as a good carrier.The photocatalytic technology-assisted adsorption technology, binary synergy purify indoor air pollutants, which will form a new type of purification technology, is of great significance for improving indoor air quality.Design the adsorption of photocatalytic materials: a multistage flower of Si O2 / Ti O2 composite materials.Mesoporous Si O2 is to adsorb organic pollutants onto the surface of the catalyst, Ti O2 play a role of the photodegradation of toxic pollutants. photocatalysis-assisted adsorption technique was still in the stage of exploration, the process of practical application is difficult to comprehensively put into effect and objectively understand its charateristics, and influence to further improve its performance, also hindered the application of reasonable and effective, economic and reliable and the expansion of the scope.Therefore the comprehensive system of theoretical and experimental research is of realistic significance.This is the purpose of this study.(1)Adsorption-photocatalytic synergistic removal of toluene vapor in air on Si O2@Ti O2 compositesNanocrystalline Si O2 was prepared by stober method, and then through the solvothermal approach, Ti O2 flower-like structures were supported on Si O2, thus obtained Si O2 @ Ti O2 composites. The influences of various factors on the adsorption and photocatalytic properties are controlled by Si O2 loading. Improving the adsorption capacity and efficiency of photocatalytic degradation of organic pollutants is aiming at achieving synergies adsorption and photocatalytic air purification. The obtained samples were characterized by SEM, TEM, XRD and XPS techniques. The fundamental adsorptionphotocatalytic behaviors were investigated in the removal of toluene vapor diluted in air. In the case of hybrid photocatalysts, the initial toluene concentration in gas phase was significantly reduced because of adsorption into the Si O2. After photo-irradiation started, toluene was continuously decomposed., out of the Si O2 etching method for structure-activity relationships and synergies adsorption and photocatalytic conducted a preliminary exploration from the inside by using Na OH. Experimental results show that, considering the adsorption and degradation of performance, the morlar ratio of Si /Ti at 6.77 for the sample can well achieve rapidly and sustain adsorption of toluene degradation, with potential applications value.(2) Immobilization of Si O2@Ti O2 nano-composite on Cu net /fiber glass and the study of its adsorption-photocatalytic performanceIn this part, first through the in-situ method Si O2 was loaded on the carrier, then use solvothermal method loading on carrier made up of Si O2 @Ti O2 flower-like structure which was successfully prepared Cu net thermal recycling in situ Si O2 @ Ti O2 and fiber glass / Ti O2 adsorption- photocatalytic nanocomposite. The obtained samples were characterized by scanning electron microscopy(SEM), transmission electron microscope(TEM), X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS) techniques. It showed that thermal technology synthetic Cu net / Si O2 @ Ti O2 and fiber glass / Ti O2 nanocomposites with uniform core-shell structure of the class, uniform size, the larger the specific surface area, the higher the degree of crystallinity, flower-like structure intact and better thermal stability. Meanwhile, Ti O2 flower-like structures on the carrier surface were uniformly dispersed, high crystallinity, and combined with a solid carrier.(3) Preparation of Si O2 @ Ti O2 nanocomposites of Au modification and the study of its adsorption-photocatalytic performanceFirst Si O2 @ Ti O2 was synthesised by a two step method, and then Au deposited on the catalyst by the precipitation process. With series characterization show the preparation of Au with uniform size modified on Si O2 @ Ti O2 nanocomposites. Experiments show that degradation of acetaldehyde on Au / Si O2 @ Ti O2 could be much better than Si O2 @ Ti O2, it may be ascribed to effect of photothermal synergies.the material to achieve continuous enrichment of the degradation of organic pollutants, has certain application prospects. |
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