A novel kind of magnetically separable photocatalyst of cerrium-doped mesoporous titanium dioxide coated magnetite (Ce/MTiO2/Fe3O4) was prepared and its activities under UV and visible light were reported.The catalysts with Ce/MTiO2 shell and Fe3O4 core were prepared by coating photoactive Ce/MTiO2 onto a magnetic Fe3O4 core through the hydrolysis of tetrabutyltitanate (Ti(OBu)4,TBT) with precursors of ammonium ceric nitrate and TBT in the presence of Fe3O4 particles.The MTiO2 shell was for photocatalysis,the Fe3O4 core was for separation by the magnetic field and the doped Ce was used to enhance the photocatalytic activity of MTiO2.The morphological,structural and optical properties of the prepared samples were characterized by Brunauer-Emmett-Teller (BET) surface area,transmission electron microscopy (TEM),X-ray diffraction (XRD) and UV-vis absorption spectroscopy.The effect of cerrium-doped content on the photocatalytic activity was studied and the result revealed that 0.5 mol.％ Ce/MTiO2/Fe3O4 exhibited highest photoactivity.The photocatalytic activities of obtained photocatalysts under UV and visible light were estimated by measuring the degradation rate of methylene blue (MB,50 mg/L) in an aqueous solution.The results showed that the prepared photocatalyst was activated by visible light and used as effective catalyst in photooxidation reactions.In addition,the possibility of cyclic usage of the prepared photocatalyst was also confirmed.Moreover,Ce/MTiO2 was tightly bound to Fe3O4 and could be easily recovered from the medium by an external magnetic filed.So,the photocatalyst can be reused without any mass loss.It can therefore be potentially applied for the treatment of water contaminated by organic pollutants.
参考文献
| [1] | Tryba B;Morawski A W;Inagaki M .A new route for preparation of TiO2-mounted activated carbon[J].Applied Catalysis B:Environmental,2003,46:203. |
| [2] | Ao CH;Lee SC;Yu JZ;Xu JH .Photodegradation of formaldehyde by photocatalyst TiO2: effects on the presences of NO, SO2 and VOCs[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,2004(1):41-50. |
| [3] | Jiang D;Zhao H;Zhang S;John R .Kinetic study of photocatalytic oxidation of adsorbed carboxylic acids at TiO2 porous films by photoelectrolysis[J].Journal of Catalysis,2004,223:212. |
| [4] | Rodrigues, AC;Boroski, M;Shimada, NS;Garcia, JC;Nozaki, J;Hioka, N .Treatment of paper pulp and paper mill wastewater by coagulation-flocculation followed by heterogeneous photocatalysis[J].Journal of Photochemistry and Photobiology. A, Chemistry,2008(1):1-10. |
| [5] | Thompson T L;Yates J T .Surface science studies of the photoactivation of TiO2.New photochemical processes[J].Chemical Reviews,2006,106:4428. |
| [6] | Yu J C;Wang X;Fu X .Pore-wall chemistry and photocatalytic activity of mesoporous titania molecular sieve films[J].Chemistry of Materials,2004,16:1523. |
| [7] | Koshitani N;Sakulkhaemaruethai S;Suzuki Y;Yoshikawa S .Preparation of mesoporous titania nanocrystals using alkylamine surfactant templates[J].Ceramics International,2006,32:819. |
| [8] | Hoffmann M R;Martin S T;Choi W;Bahnemann D W .Influence of mesoporous and platinum-modified titanium dioxide preparation methods on photocatalytic activity in liquid and gas phase[J].Applied Catalysis B:Environmental,2007,77:35. |
| [9] | Bosc F;Edwards D;Keller N;Keller V;Ayral A .Mesoporous TiO2-based photocatalysts for UV and visible light gas-phase toluene degradation[J].Thin Solid Films: An International Journal on the Science and Technology of Thin and Thick Films,2006(1/2):272-279. |
| [10] | Rachel A;Subrahmanyam M;Boule P .Comparison of photocatalytic efficiencies of TiO2 in suspended and immobilised form for the photocatalytic degradation of nitrobenzenesulfonic acids[J].Applied Catalysis B:Environmental,2002,37:301. |
| [11] | Hirashima H.;Balek V.;Imai H. .Preparation of meso-porous TiO2 gels and their characterization[J].Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites,2001(1/3):96-100. |
| [12] | Yang p;Zhao D;Margolese D I;Chmelka B F Stucky G D .Block copolymer templating syntheses of mesoporous metal oxides with large ordering lengths and semicrystalline framework[J].Chemistry of Materials,1999,11:2813. |
| [13] | Zhou M H;Yu J G;Cheng B .Effects of Fe-doping on the photocatalytic activity of mesoporous TiO2 powders prepared by an ultrasonic method[J].Journal of Hazardous Materials,2006,137:1838. |
| [14] | Asahi R;Morikawa T;Ohwaki T;Aoki K Taga Y .Visible light photocatalysis in nitrogen-doped titanum oxides[J].Science,2001,293:269. |
| [15] | Yu J G;Xiang Q J;Zhou M H .Preparation,characterization and visible-light-driven photocatalytic activity of Fe-doped titania nanorods and first-principles study for electronic structures[J].Applied Catalysis B:Environmental,2009,90:595. |
| [16] | Xie Y;Yuan C .Visible-light responsive cerium ion modified titania sol and nanocrystallites for X-3B dye photodegradation[J].Applied Catalysis B:Environmental,2003,46:251. |
| [17] | Shi H X;Zhang T Y;Wang X;He M Qiu M Y .Preparation and photocatalytic activity of multicomponent nano-TiO2/zeolite modified by rare earth and heteropolyacid[J].J Chin Society Rare Earth (in Chin ),2011,29:55. |
| [18] | Xu A W;Gao Y;Liu H Q .The preparation,characterization,and their photocatalytic activities of rare earth-doped TiO2 nanoparticles[J].Journal of Catalysis,2002,207:151. |
| [19] | Liu, ZL;Guo, B;Hong, L;Jiang, HX .Preparation and characterization of cerium oxide doped TiO2 nanoparticles[J].The journal of physics and chemistry of solids,2005(1):161-167. |
| [20] | YAO Shuhua,SUI Chcngcheng,SHI Zhongliang.Preparation and characterization of visible-light-driven europium doped mesoporous titania photocatalyst[J].稀土学报（英文版）,2011(10):929-933. |
| [21] | Yu X X;Liu S W;Yu J G .Superparamagnetic γ-Fe2O3@SiO2@TiO2 composite microspheres with superior photocatalytic properties[J].Applied Catalysis B:Environmental,2011,104:12. |
| [22] | Oliveir L C A;Rios R V R;Fabris J D;Garg V Sapag K Lago R M .Activated carbon/iron oxide magnetic composites for the adsorption of contaminants in water[J].Carbon,2002,40:2177. |
| [23] | Gregg S J;Sing K S W.Adsorption,Surface Area and Porosity[M].London,UK:Academic Press,1982 |
| [24] | Sing K S W;Everett D H;Haul R A W;Moscou L Pierotti R A Rouquerol J Siemieniewska V T .Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity[J].Pure and Applied Chemistry,1985,57:603. |
| [25] | Yamada T;Kayano K;Funabiki M .Platinum metals-ceria synergism in autoexhaust catalyst[J].Studies in Surface Science and Catalysis,1993,77:329. |
| [26] | Gerischer H;Heller A .The role of oxygen in photooxidation of organic molecules on semiconductor particles[J].Journal of Physical Chemistry,1991,95:5261. |
| [27] | Beydoun D;Amal R;Low G;McEvoy S .Occurrence and prevention of photodissolution at the phase junction of magnetite and titanium dioxide[J].Journal of Molecular Catalysis A:Chemical,2002,180:193. |
| [28] | Navio J;Macias M;Gonzalez-Catalan M;Justo A .Bulk and surface characterization of powder iron-doped titania photocatalysts[J].Journal of Materials Science,1992,27:3036. |
| [29] | Ranjit K T;Viswanthan B .Synthesis,characterization and photocatalytic properties of iron-doped TiO2 Catalysts[J].Journal of Photochemistry and Photobiology A:Chemistry,1997,108:79. |
| [30] | Beydoun D;Amal R .Novel photocatalyst:Titania-coated magnetite[J].Activity and photodissolution J Phys Chem B,2000,104:4387. |
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