Preparation And Photocatalytic Performance Of The Doped,Composited And Loaded TiO₂

In order to improve TiO2 photocatalysis,to solve in practical application of TiO2 powders reused difficultly,this paper prepared TiO2,Fe3+ doped TiO2,up-conversion luminescent materials composited TiO2 by using sol-gel method,and loading on vitrified or non-vitrified expanded perlite(YEP or WEP)and porous ceramics(TC).The samples were tested by carrying out XRD,SEM,EDX,XPS,and UV-vis.The photocatalytic degradation experiments were carried out on MB in the dark,visible light and 19 W ultraviolet light(253.7nm)and illumination at 130-1501ux,respectively.The results are as follows.Anatase is the main phase in TiO2,Fe3+ doped TiO2,up-conversion luminescent materials composited TiO2,and TC,WEP,YEP loaded TiO2,Fe3+ doped TiO2,and up-conversion luminescent material commposited TiO2,respectively.Loading Fe3+ doped TiO2 without the appearance of new peaks,Up-conversion luminescent materials composited TiO2 have new peaks of Er3+ NaYF4 in 31° and 47°.To visible light,Fe3+doped TiO2 absorption limit extended to 650nm-750 nm,the absorption limit of up-conversion luminescent materials composited TiO2 moves to about 420 mm.The weak absorption peaks of Er3+ in Er3+·NaYF4 appeared in 480 nm to 520 mm The binding energy of oxygen and titanium element in Fe3+ doped TiO2 or in Up-conversion luminescent materials composited TiO2 all decreased,it shows the titanium and oxygen connection mode has changed due to doping or composite effect.The particle size of TiO2,Fe3+ doped TiO2,and up-conversion luminescent materials composited TiO2 are around 2-6 μm distributed on the surface of WEP,YEP and TC.After loading,the iron and titanium content on the surface of the carrier Fe3+doped TiO2 is higher than that of pure carrier.The titanium content on the surface of loaded up-conversion luminescent materials composited TiO2 is higher than that pure carrier;fluoride,Y and F can be detected,Er also be detected in a sample.Under visible light,P25 and self-prepared TiO2 have no effect on the MB.But it can be degradated by Fe3+ doped TiO2 and up-conversion luminescent materials composited TiO2After the adsorption of MB in the dark,the degradated mass ratio(replaced by KT)of MB has increased nearly 9 times by loading Fe3+ doped TiO2,which is compared with those without loading powdery samples.and it also exceeds the KT of MB by loading Fe3+ doped TiO2 under ultraviolet irradiation.The results show that they have efficiently increased the visible light photocatalyses of TiO2 by Fe3+-doped TiO2 and its loaded.Without adsorption,but directly photocatalytic degradation of MB under ultraviolet light or visible light,match adsorption amount with photocatalytic degradation amount of MB,that can improve the efective catalyst of TiO2.Under visible and UV light,the degradation effect to MB of the up-conversion luminescent materials composited TiO2 prepared in ultrasonic stirring process better than that of mechanical stirring method.Under visible light irradiation,up-conversion luminescent materials cormposited TiO2 which is loaded on porous ceramics(TC),the KT of photocatalytic degradation of MB significantly improve,outstrip the KT of loading TiO2 or the KT of these up-conversion luminescent materials composited TiO2 Which are not loaded on porous ceramics(TC).Under direct visible light irradiation without the adsorption of MB in the dark,the KT of degradation effect to MB is higher by loading up-conversion luminescent materials composited TiO2.The results show that they have efficiently increased the visible light photo catalyses of TiO2 by up-conversion luminescent materials composited TiO2 and its loaded.Without adsorption,but directly photocatalytic degradation of MB under ultraviolet light or visible light,match adsorption amount with photocatalytic degradation of MB,which can improve the effective catalyst of TiO2.Through four tests of cycle photo catalytic to MB,the degradation ratio of MB by loaded TiO2,loaded Fe3+ doped TiO2,and loaded up-conversion luminescent materials composited TiO2,which are on WEP,YEP or TC,decreased respectively in some different degree.Comparison these results you can know the decreased level of four degrading MB by loaded Fe3+ doped TiO2 or loaded up-conversion luminescent materials composited TiO2 on YEP faIl less than others,the load-process can slow down the degradation ratio reduction of samples cycle photo catalytic to MB,extend their reused life.