Preparation And Photocatalytic Performance Of Cone Shaped Titanate/PAN Nanofiber

Due to its unique optical drive and excellent performance,photocatalyst provided an effective solution for environmental and energy crisis.Efficient photocatalysts were mostly nano-sized powder materials.However,nano-sized photocatalysts were difficult to be recollected from solution after photocatalysis and easy to cause secondary pollution,which limited its application in industrial production and daily life.Nanofibers with large specific surface area could be used to support nano-sized photocatalysts.It could not only reduce the agglomeration of nano-sized powders but also facilitate the recovery of photocatalysts.In this paper,the composite material(HTO@?-TiO2@f-PAN NF),based on polyacrylonitrile nanofibers,was prepared by the depositon of ?-TiO2 layer and cone-shaped titanate(H2Ti5O11·3H2O,HTO)on nanofibers successively.The growth mechanism of the composite material was studied by the exploration of its preparation conditions.Rhodamine B(RhB)aqueous solution and tetracycline(TC-HCl)aqueous solution were used as model pollutions to study the photocatalytic property of the composite material.The main work were as follows:(1)Carboxylated polyacrylonitrile(C-PAN)was prepared by solution copolymerization.Fiber-forming polymer was prepared by the blend of C-PAN and commercial polyacrylonitrile(mass ratio was 1:1),and dissolved in N,N-Dimethylformamide(DMF)to get spinning solution(the concentration was 13 wt%).Functional polyacrylonitrile nanofibers(f-PAN NF)acted as the carrier of photocatalyst by electrospinning.The ?-TiO2 layer and titanate were loaded on nanofibers successively to get the composite material.Through the exploration of the growth conditions of composite material,it was inferred that under the action of ?-TiO2 layer and cyanuric acid(shape control agent),titanate with cone-shape could be grown on the surface of nanofibers.By the screening of the micro-morphology and photocatalytic properties of the composite material,the optimum sample was obtained when the reaction time was 36 h.(2)It was found that the composite material could response to ultraviolet light and visible light somewhat.Under the irradiation of LED lamp,the composite material had significant photocatalytic effect on rhodamine B(RhB)aqueous solution and TC-HCl aqueous solution,the degradation efficiency was 82.2%and 54.2%successively.In addition,when the composite material was stained with RhB aqueous solution and pitaya juice respectively,it exhibited excellent photobleaching performance under the illumination of LED lamp as well.Within 2 h of illumination,there would be obvious fading phenomenon.