Study And Optimization Of Photocatalytic Performance Of BiVO₄ Nanofibers Prepared By Electrospinning

Environment has been badly polluted because of the development of the industry and the growing population,especially the organic dye waste water pollution.A highly active and environmental protection method is being needed to deal with this situation.Recently,researchers prefer photocatalytic method because of its mild reaction condition and simple operation,at the same time,the second environmental pollution is very small,all these made it a very promising way of solution.For BiVO₄ material,non-toxic,chemical stability and it has a narrow band-gap,so all these characteristics made it a research hot spot as the new photocatalytic material of semiconductor.This paper is focused on BiVO₄ photocatalyst of visible light,use electrospinning technology to prepare BiVO₄ nanofiber material,apply ultraviolet?UV?reduction to prepare Ag₂O-BiVO₄ composite semiconductor material in order to improve photocatalytic performance,the factors affecting the photocatalytic activity and the cycle stability were also discussed.The main contents of this paper are as follows:1.Use Bi?NO₃?₃?5H₂O as Bi source,VO?acac?₂ as V source,DMF as solvent,PVP as spinning aid,apply electrospinning technology to prepare long range continuous BiVO₄ nanofiber,then find out the best photocatalytic activity.Prepare samples of three different temperatures via changing the calcination temperature,we found that the best crystallinity comes out at 500 oC,specific surface area is up to 29.14m²/g,and the degradation rate of Rhodamine B reaches 89.3% which has already become the best preparation condition.And the cycle stability has been studied.XRD pattern of contrast before and after the photocatalytic reaction,indicates its good stability and its effect on methylene blue is further explored.2.Use silver nitrate as Ag source,apply UV light reduction method to improve the photocatalytic activity of 500 oC BiVO₄'s surface,loaded by Ag₂O,we can tell from the characterization that crystal structure of the samples was not affected by Ag₂O,however,the catalytic performance is improved obviously.The reason is the formation of p-n type composite semiconductor material,which suppressed the recombination of electron-hole pairs photogenerated,then improve the photocatalytic performance and the degradation rate can reach 98.47% when the load of Ag₂OBiVO₄ is 10%.And further more,when the load is 10% of Ag₂O-BiVO₄,explore the photocatalytic degradation of Rhodamine B effected by catalyst dosage and dye concentration is explored.And analyze the reaction mechanism of Ag₂O-BiVO₄ composites in the photocatalytic process.At the same time,the cycle stability experiments show that it is a reusable material.Finally,the adsorption performance of Ag₂O-BiVO₄ composite semiconductor material on the non metallic I-in waste water was studied.It was found that when the initial concentration was 20 mg/l,the adsorption equilibrium was reached at 8 h,and the adsorption capacity was up to 18 mg/g,so the compound semiconductor materials can also handle radioactive waste water.