Feng Yujie, Cui Yuhong, Logan Bruce, Liu Zhengqian
Department of Environmental Science and Engineering, Harbin Institute of Technology, No. 202, Haihe Road, Nangang District, Harbin 150090, China.
Chemosphere. 2008 Feb;70(9):1629-36. doi: 10.1016/j.chemosphere.2007.07.083. Epub 2007 Oct 24.
The performance of electrodes for the electro-catalytic decomposition of a model pollutant (phenol) was enhanced using Gd-doped Ti/SnO(2)-Sb electrodes prepared by a thermal deposition method. Phenol degradation followed first-order rate kinetics, with the maximum rate achieved using a 2% Gd doping level (molar ratio based on Gd:Sn) for tests conducted over a doping range of 1-10%. The first-order rate constant with 2% Gd was 0.044 min(-1), versus 0.026 min(-1) obtained with the control (plain Ti/SnO(2)-Sb). TOC removal and UV scans revealed that different intermediates were produced for different Gd contents, and that destruction efficiencies of these intermediates also varied with Gd doping levels of 1-5%. Electrodes were characterized by scanning electron microscopy, X-ray diffraction, electron dispersive spectrometry, and X-ray photon-electron spectroscopy. It is suggested that the state of specific active sites on the electrode surface and the oxygen transfer activity at the electrode/electrolyte interface affect the performance of anodes with different compositions.
通过热沉积法制备的钆掺杂钛/二氧化锡-锑电极，提高了对一种典型污染物（苯酚）进行电催化分解的电极性能。苯酚降解遵循一级动力学速率，在1%-10%的掺杂范围内进行测试时，使用2%的钆掺杂水平（基于钆与锡的摩尔比）可达到最大降解速率。2%钆掺杂时的一级速率常数为0.044 min⁻¹，而对照电极（普通钛/二氧化锡-锑电极）的该常数为0.026 min⁻¹。总有机碳去除率和紫外扫描显示，不同钆含量会产生不同的中间体，并且这些中间体的降解效率也随1%-5%的钆掺杂水平而变化。通过扫描电子显微镜、X射线衍射、电子能谱和X射线光电子能谱对电极进行了表征。研究表明，电极表面特定活性位点的状态以及电极/电解质界面处的氧转移活性会影响不同组成阳极的性能。
