| Photocatalytic oxidation is technology for removal of pollutants from aqueous and air stream by using the semiconductors photocatalyst.Its can provide new methods for the industrialized treatment of organic pollutions and has widely used because of high-efficiency,non-selective degradation,easily controlled operation conditions,no secondary pollution.At present,the semiconductor photocatalysts with wide band gap are merely responded ultraviolet spectrum.It is difficult to accomplish availably transform and utilization of solar energy.So developing a new visable light response semiconductor photocatalysts(spinel-type AB2O4)becomes a new researchful hot spot about photocatalyst research.In this paper,the spinel-type Cu(MxAly)2O4(M= Cr?Fe?Mn)are prepared by sol-gel process method.With XRD,testing means,we investigate the framework of crystal.The photo-degradation experiments of various water-soluble dyes including Reactive brilliane red K-2G,acid red B are carried out in the suspension systems of spinels acting as photocatalysts.The photocatalytic activity of various spinels is described by the decolored rate.Spinel-type Cu(CrxAly)2O4?Cu(FexAly)2O4photocatalyst prepared by hydrothermal method with the better photocatalytic character is studied particularly.The impact of the heat treatment conditions and the mixture ratio upon its photocatalytic character and photoelectric conversion efficiency is discussed.The results of the study show that using sol-gel method can be preparation spinel Cu(MxAly)2O4(M= Cr?Fe?Mn)in low temperature,and at the same time,precursor compound of precursors got spinel Cu(MxAly)2O4(M= Cr?Fe?Mn)sample by heat treatment system.Through the photocatalytic activity of the Cu(MxAly)2O4(M= Cr?Fe?Mn)found that three sample are excellent photocatalytic catalytic properties,three kind of dye solution degradation decoloring rate achieve 80%after catalytic degradation 2 h.Cu(MxAly)2O4(M= Cr?Fe)photocatalytic catalytic activity analysis shows that the heat treatment temperature and mixing ratio of Cu(MxAly)2O4(M= Cr.Fe)sample have a great impact on the photocatalytic catalytic activity,and the reaction temperature at 800 ?,x = 0.2,y = 0.8 system samples of catalytic degradation effect is best for acid red B,degradation decoloring rate is above 90%After the irradiation about 2 hours.A method of spinel Cu(M0.2Al0.8)2O4(M= Cr?Fe)and TiO2 powders,by the photoelectric conversion efficiency testing,the results show that when adding 1%of Cu(Fe0.2Al0.s)2O4 powder,the photoelectric conversion efficiency is 2.91%,and when adding 3%of Cu(Cr0.2Al0.8)2O4Powder,the photoelectric conversion efficiency of the best for 3.59%.with Ni0.4 Cu0.6 A12O4nano spinel powder to keep fresh pears and bananas,it found that powder has good preservation freshness effect to pears and bananas,fruit rot can be extended by 4?5 days. |
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