Research On The Degradation Of Formaldehyde Gas By Different Morphology Of Modified Bi₂WO₆ Composite In Visible Light

Bi₂WO₆ has visible light catalytic activity.It can degrade most of the organic pollutants under visible light.With the 2d layer structure can be self-assembled,the morphology of Bi₂WO₆ can be easily controlled by us,so it is favored by many researchers.What's more,because of it's unique geometry and electronic structure,graphene has the low carrier concentration,larger specific surface area?2630 m2/g?,higher strength?130 GPa?and electron mobility?200,000 cm2·V-1·s-1?,become the ideal modified material of Bi₂WO₆.First of all,we explore the graphite oxide preparation conditions in this article.Then,on the carrier of graphene,we prepared the graphene load Bi₂WO₆.Finally,we analyzed the activity of the catalyst using formaldehyde as aimed pollutants in visible light.Specific content is as follows:1.We explored the preparation influence factors of graphite oxide?GO?.We studied the effects on graphite oxidation degree from the four aspects: raw materials,high temperature oxidation time,the rate of KMnO4 added and medium temperature reaction time.The experimental results show that under the medium temperature condition,choose a specific right material,is more beneficial for the graphite intercalating oxidation.When the midum temperature time is extended to 10 h,we got the best result and the layer spacing reach 8.73 ?.2.Use the GO we just prepared as the carrier,Bi?NO3?3·5H2O and Na2WO4·2H2O as reactant,under different pH,We prepared GO/BWO with different mass ratios of GO using hydrothermal method.And then we restore the GO/BWO with ethylene glycol?EG?,get the Bi₂WO₆ catalyst sample supported by graphene.3.We characterize the sample using XRD,FT-IR,SEM,TEM and other means.The results revealed that GO was only 3⁵ layers use the medium temperature reaction method.Under neutral conditions,we get a two-dimensional flake-Bi₂WO₆ crystal.However,we get a three-dimensional flower-Bi₂WO₆ crystal under acidic conditions.4.With formaldehyde gas as the target pollutant,we explored the activity of different catalysts in visible light under the same degradation conditions.It turn out that under acidic conditions,GO loading amount was 1%,the sample GO/BWO-S1 have the highest catalytic activity.When it was irradiated under visible light for 3 h,the formaldehyde gas was removed for 67.10%.