物理化学学报 >> 2011, Vol. 27 >> Issue (11): 2726-2732.doi: 10.3866/PKU.WHXB20111131

材料物理化学 上一篇    

不同形态铈改性的TiO2纳米管阵列的制备及其可见光光电响应性质

张胜寒, 梁可心, 檀玉   

  1. 华北电力大学环境科学与工程学院, 河北保定 071003
  • 收稿日期:2011-06-17 修回日期:2011-08-30 发布日期:2011-10-27
  • 通讯作者: 梁可心 E-mail:kexin91802@163.com
  • 基金资助:

    中央高校基本科研业务费(11QX79)资助项目

Preparation of TiO2 Nanotube Arrays with Different Cerium Mixing Morphology and Their Photoelectrochemical Response in Visible Light

ZHANG Sheng-Han, LIANG Ke-Xin, TAN Yu   

  1. School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, Hebei Province, P. R. China
  • Received:2011-06-17 Revised:2011-08-30 Published:2011-10-27
  • Contact: LIANG Ke-Xin E-mail:kexin91802@163.com
  • Supported by:

    The project was supported by the Fundamental Research Funds for the Central Universities, China (11QX79).

摘要: 采用电化学阴极还原和阳极氧化法, 制备了还原态铈和氧化态铈改性的TiO2纳米管阵列, 通过扫描电子显微镜(SEM)和X射线衍射(XRD)表征样品形貌和晶相, 得出还原态铈以单质铈纳米纤维形式存在于TiO2纳米管内及表面, 单质铈改性的TiO2纳米管经阳极氧化后, 以CeO2和单质Ce形式共存. 测定样品的光电流响应并计算样品的能带宽度. 结果表明: 单质铈改性的TiO2纳米管阵列在可见光区光电流响应较TiO2纳米管增强,单质铈添加存在最佳值, 在10 mmol·L-1溶液中制备的单质铈改性的TiO2纳米管阵列光电流响应最强, 能带宽度Eg减少到2.88 eV, 并且随着单质铈含量的增加, 载流子浓度增大, 且平带电位向负向移动. 单质铈改性的样品经阳极氧化后, 样品在紫外光区和可见光区光电流响应都增强, 但其在可见光区的响应强度要小于单质铈改性的TiO2纳米管在可见光区的响应强度.

关键词: TiO2纳米管阵列, 铈, 氧化铈, 共催化, 可见光, 光电流响应, 半导体特性

Abstract: Well-ordered TiO2 nanotube arrays were prepared by electrochemical anodization onto a pure Ti sheet in an organic solution. Reduced cerium and oxidized cerium were deposited onto the TiO2 nanotube arrays by electrochemical cathodic reduction and then anodic oxidation. The morphology and crystalline phase were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), which indicated that the reduced cerium was in the form of elemental cerium nanofibers and they were dispersed over the surface of the TiO2 nanotube. The oxidized cerium was present as elemental cerium and cerium dioxide after oxidation. The photocurrent was measured and the bandgap energies were calculated. The results showed that the photocurrent response of the TiO2 nanotube arrays modified by the reduced cerium was enhanced in the visible spectra rather than in the UV spectra. The optimum amount of deposition was found for the sample prepared using the 10 mmol·L-1 cerium nitrate solution and with a bandgap energy of 2.88 eV. Also, the carrier density increased and the flat band potentials moved to the negative direction as the cerium content increased. After anodic oxidation, the photocurrent response of the samples increased in the visible spectra and in the UV spectra. However, the photocurrent response modified by oxidized cerium in visible spectra is weaker than that of the TiO2 nanotube arrays modified by reduced cerium.

Key words: TiO2 nanotube array, Cerium, Cerium dioxide, Co-catalysis, Visible light, Photocurrent response, Semiconductor characteristics

MSC2000: 

  • O643