物理化学学报 >> 2012, Vol. 28 >> Issue (08): 1978-1984.doi: 10.3866/PKU.WHXB201205172

催化和表面科学 上一篇    下一篇

Bi3.25La0.75Ti3O12纳米线的可见光催化性能

林雪1,2, 吕鹏1, 关庆丰1, 李海波3, 李洪吉2, 蔡杰1, 邹阳1   

  1. 1. 江苏大学材料科学与工程学院, 江苏 镇江 212013;
    2. 吉林师范大学化学学院, 环境友好材料制备与应用教育部重点实验室, 吉林 四平 136000;
    3. 吉林师范大学物理学院, 吉林 四平 136000
  • 收稿日期:2012-04-09 修回日期:2012-05-17 发布日期:2012-07-10
  • 通讯作者: 关庆丰 E-mail:guanqf@ujs.edu.cn
  • 基金资助:

    环境友好材料制备与应用教育部重点实验室项目资助

Visible Light Photocatalytic Properties of Bi3.25La0.75Ti3O12 Nanowires

LIN Xue1,2, Lü Peng1, GUAN Qing-Feng1, LI Hai-Bo3, LI Hong-Ji2, CAI Jie1, ZOU Yang1   

  1. 1. School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu Porvnce, P. R. China;
    2. College of Chemistry, Key Laboratory of Preparation and Application Environmentally Friendly Materials of the Ministry of Education, Jilin Normal University, Siping 136000, Jilin Porvnce, P. R. China;
    3. College of Physics, Jilin Normal University, Siping 136000, Jilin Porvnce, P. R. China
  • Received:2012-04-09 Revised:2012-05-17 Published:2012-07-10
  • Contact: GUAN Qing-Feng E-mail:guanqf@ujs.edu.cn
  • Supported by:

    The project was supported by the Key Laboratory of Preparation and Application Environmentally Friendly Materials of the Ministry of Education of China.

摘要:

研究了用一步水热法制备的掺镧钛酸铋(Bi3.25La0.75Ti3O12, BLT)纳米线的光学和可见光催化性能, 并对其晶体结构和微观结构用X射线衍射(XRD)、透射电子显微镜(TEM)和高分辨透射电子显微镜(HRTEM)等手段进行了表征. 结果表明, 制备的纳米线为纯相的Bi3.25La0.75Ti3O12, 平均直径约为25 nm. 室温光致发光谱(PL)显示BLT纳米线在433和565 nm附近有较强的发射峰, 分别对应激子发射和表面缺陷发光. 紫外-可见漫反射光谱(UV-Vis DRS)表明BLT样品的带隙能约为2.07 eV. 利用可见光(λ>420 nm)照射下的甲基橙降解实验评价了BLT样品的光催化性能. 结果表明, BLT的光催化活性比商用TiO2催化剂P25、掺氮TiO2和纯相钛酸铋(Bi4Ti3O12, BIT)高得多. BLT光催化剂具有更高催化活性的原因是La3+离子掺杂拓展了BIT对可见光的吸收范围, 同时抑制了BIT的光生电子-空穴的复合.

关键词: 钛酸铋, 掺镧, 纳米线, 水热合成, 光催化降解, 可见光照射

Abstract:

Lanthanum-doped bismuth titanate (Bi3.25La0.75Ti3O12, BLT) nanowires were synthesized by a one-step hydrothermal process and their optical and photocatalytic properties were investigated. Their crystal structure and microstructures were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The BLT nanowires obtained are single-phase with an average diameter of 25 nm. The room temperature photoluminescence (PL) spectrum reveals two visible emission peaks at 400 and 596 nm, which are assigned to excitonic and surface-defect emissions, respectively. The UV-visible diffuse reflectance spectrum (UV-Vis DRS) reveals that the band gap of BLT nanowires is 2.07 eV. The prepared BLT nanowires are stable and exhibit higher photocatalytic activities in the degradation of methyl orange (MO) under visible light irradiation (λ >420 nm) compared with commercial P25 TiO2, traditional N-doped TiO2 (N-TiO2), and pure bismuth titanate (Bi4Ti3O12, BIT). The high photocatalytic performance of BLT photocatalysts is attributed to the strong visible light absorption and the recombination restraint of the e-/h+ pairs resulting from the presence of La3+ ions.

Key words: Bismuth titanate, Lanthanum doping, Nanowire, Hydrothermal synthesis, Photocatalytic degradation, Visible light irradiation

MSC2000: 

  • O643