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Environmental pollution and energy shortage become the obstacles of the continualdevelopment of human being, and photocatalytic technology has attracted wide attention onenvironmental treatment. Na2Ti6O13is a function material widely used in the fields ofmaterialogy, photoelectricity, environmentology etc. And it can be synthesised into1Dnanomaterials,so, the photocatalytic activity of Na2Ti6O13has important significance forpractical application of photocatalytic technology.In this dissertation,1D Na2Ti6O13nanobelts and Na2Ti6O13/TiO2composite catalyst wereprepared by the combination of reverse microemulsion method and molten salt method, theirUV photocatalytic activity and kinetic models were studied systematically, and the effects ofreaction conditions on photocatalytic activities were also investigated, in which reactivebrilliant orange X-GN was setted as the target pollutant. The main research contents andconclusions are as follows:At the first,The phase behavior of CTAB/n-hexanol/water reverse microemulsionsystem was investigated by ternary phase diagram analysis and electrical conductivityresearch, and found out the optimum components proportion for preparing nano-precursorTi（OH）4, whose mass fraction are9.6%（CTAB）,86.8%（n-hexanol） and3.6%（water）.Furtherly, the precursor Ti（OH）4was characterized by SEM, TG-DSC, FT-IR and XRD, Theresults showed that the precursor are “droplet-shape” particles, whose particle size is about100nm, and their surface have some residual organics.Then the precursor and Na2CO3were used to fabricate1D Na2Ti6O13nanobelts bymolten salt method. The Na2Ti6O13nanobelts obtained by heating at810℃and holding atthis temperature for6h achieved the best photocatalytic activity, and they are1D nanomaterials whose length are5-8μm, when their width and thickness are less than80nm.Na2Ti6O13/TiO2composite catalysts were prepared by reverse microemulsion method andmolten salt method respectively, and the samples were evaluated by XRD, SEM andphotocatalytic tests, the results revealed that the catalysts composited by reverse microemulsion method showed better photocatalytic activity, and RM1.5-Na2Ti6O13/TiO2is thebest among them. In contrast, the products prepared by molten salt method showed badcatalytic effect.At last, the photocatalytic degradation experiments of X-GN were conducted underUV-light, and the degradation rate, mineralization rate, kinetic models and UV-VIS spectrumswere studied systematically, the results showed that the degradation processes, which werecatalyzed by RM1.5-Na2Ti6O13/TiO2, M810-Na2Ti6O13and MS7:1-Na2Ti6O13/TiO2, fit the firstorder kinetic model, RM1.5-Na2Ti6O13/TiO2have the best performance among them, whileM810-Na2Ti6O13have some intermediate products accumulation. Furthermore, the effects ofdifferent reaction conditions were also studied in photocatalysis reactions catalyzed byRM1.5-Na2Ti6O13/TiO2and M810-Na2Ti6O13, the results demonstrated that the optimum initialpH value of RM1.5-Na2Ti6O13/TiO2and M810-Na2Ti6O13is3.2and5.7respectively; A positivecorrelation existed between the degradation rate and photocatalyst dosage within proper range,but it turned to the opposite trend when the dosage exceeded a certain limit; The degradationrate and the initial X-GN concentration had an inverse correlation; The addition of H2O2canobviously improve the degradation efficiency.
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