以玉米秸秆为模板,采用溶胶-凝胶法制备N掺杂FeVO4光催化剂,采用 X射线衍射(XRD)、扫描电镜(SEM)、比表面积分析(BET)、X射线光电子能谱(XPS)、紫外-可见吸收光谱(UV-Vis)等测试、分析手段,对样品进行表征。在可见光照射下,通过光催化降解甲基橙溶液评价N 掺杂对 FeVO4光催化剂活性的影响。结果表明,掺杂 N 前后 FeVO4均为三斜型, N取代了 FeVO4晶格中 O 形成了 N-Fe-O 键,产生了杂质能级,N掺杂导致FeVO4表面形成了大量束缚单电子的氧空位,产生缺陷能级,二者共同作用致使带隙窄化,光吸收带红移。光催化降解结果表明,N 掺杂能有效提高 FeVO4的可见光催化活性。当掺杂 N为15%(摩尔分数)时,样品活性最高,光照100 min对甲基橙的脱色率达56%左右,远高于未掺杂的脱色率(16.7%)。
N-doped FeVO4 photocatalysts were successfully prepared via sol-gel method with the corn stem as template.The samples were characterized by X-ray diffraction (XRD),scanning electron microscope(SEM), specific surface area(BET),X-ray photoelectron spectroscopy (XPS)and UV-Vis absorption spectroscopy(UV-Vis).The photocatalytic activity was evaluated by photocatalytic degradation of methyl orange (MO)solution under visible light.The results showed that all the FVO or N/FVO photocatalysts were consisted of triclinic phase.The enhanced photocatalytic activity was ascribed to a synergic effect of impurity energy levels due to the substitutional N-doping forming the N-Fe-O bonding structures and defect energy levels resulted from the formation of oxygen vacancies,which result in the band gap narrowing and red-shift of optical absorption band. The appropriate amount of N doping can signifcantly increase the photocatalytic activity and the highest photo-catalytic degradation rate can be about 56% in 100 min when then doping amount was 15%,which was 40% or so than that of pure FeVO4 under visible light irradiation.
参考文献
| [1] | 戈磊.新型Pt/BiVO4可见光活性光催化剂的制备和表征[J].无机材料学报,2008(03):449-453. |
| [2] | 张永来,丁红,刘福建,魏舒,刘森,和东亮,肖丰收.Ag3VO4纳米粒子的合成及其对可见光下降解罗丹明B的催化活性[J].催化学报,2008(08):783-787. |
| [3] | Zhou Lin;Wang Wenzhong;Liu Shengwei et al.A sonochemical route to visible-light-driven high-acitvity Bi-VO4 photocatalyst[J].J Mole Catal A:Chem,2006,252:120-124. |
| [4] | Hu Xuexiang;Hu Chun .Preparation and visible-lighttphotocatalytic activity of Ag3 VO4 powders[J].J Solid Chem,2007,180:725-732. |
| [5] | Suresh Rao N;Palanna O G .Electrical and magetic stud-ies of iron(Ⅲ)vanadate[J].Mater Acienc,1995,18:229. |
| [6] | Masatoshi H;Mika E;Takashi M et al.Lithiation char-acteristics of FeVO4[J].Solid State Ionicis,1997,98:119. |
| [7] | Sato S .The structure and properties of endohedral fullerenes[J].CHEMICAL PHYSICS LETTERS,1986,123:126. |
| [8] | Asahi R;Morikawa T;Ohwaki T et al.Visible-lighttphotocatalysis in nitrogen-doped titanium oxides[J].Sci-ence,2001,293:269. |
| [9] | Irie H;Watanabe Y;Hashimoto K J .Nitrogen-concen-tration dependence on photocatalytic activity of TiO2-x Nx Powders[J].Physical Chemistry B,2003,107:5483. |
| [10] | Aditi R G;Julio B F .Photocatalytic destruction of VOCs in the gas-phase using titanium dioxide[J].Solid State Chemistry,2005,178:2953. |
| [11] | 梁慧荣,张耀君,郭烈锦.N掺杂Ta2O5的制备及其光催化分解水制氢性能研究[J].太阳能学报,2006(10):1032-1036. |
| [12] | Asahi R;Morikawa T;Ohwaki T et al.Visible-lighttphotocatalysis in nitrogen-doped titanium oxides[J].SCIENCE,2001,293:269. |
| [13] | Ohno T;Mitsui T;Matsumura M .Photocatalytic activ-ity of S-doped TiO2 photocatalyst under visible light[J].CHEMISTRY LETTERS,2003,32:364. |
| [14] | Khan S U M;Al-Shahry M;Ingler Jr W B .Efficient photochemical water splitting by a chemically modified N-TiO2[J].SCIENCE,2002,297:2243. |
| [15] | Huang B B;Dai Y;Wang Y B et al.Density functional characterization of the band edges[J].Energy Environ Sci,2010,3:1128. |
| [16] | 徐爱菊,照日格图,贾美林,刘莲云.Co3V2O8催化剂的合成表征及其催化性能研究[J].燃料化学学报,2009(02):252-256. |
| [17] | Wagner C D;Riggs W M;Davis LE.Handbook of X-ray photoelectron spectroscopy[M].USA:Perkin El-mer Corp,1990 |
| [18] | Sato S;Nakamura R;Abe S .Visible-light sensitization of TiO2 photocatalysts by wet-method N doping[J].Appl Cata1 A,2005,284:131-137. |
| [19] | Valentin C D;Pacchioni G;Selloni A et al.Character-ization of paramagnetic species in N-doped TiO2 powders by EPR spectroscopy and DFT calculations[J].Journal of Physical Chemistry B,2005,109:111414. |
| [20] | Kim D;Fujimoto S;Schmuki P et al.Preparation of TiO2 nanotube on glass by anodization of Ti films at room temperature[J].ELECTROCHEMISTRY COMMUNICATIONS,2008,10:910. |
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