高电子传输和催化活性PbO_(2)电极的制备及其对苯达松的氧化降解研究

Fabrication of PbO electrode with high electron transmission and high electrocatalytic activity,and study on its application for bentazon degradation

以还原态TiO_(2)纳米管和纳米金刚石为电极中间层和催化层掺杂改性剂,通过电沉积法制备了新型PbO_(2)电极(Ti/TiO_(2)-RNTs/Sb-SnO_(2)/PbO_(2)-ND)。合成的电极表面主要为β-PbO_(2)晶体,晶粒尺寸是17 nm。电化学分析测试表明,还原态TiO_(2)纳米管中间层和纳米金刚石掺杂改性减少了电极电荷转移电阻,增加了电极的析氧电位和电化学活性面积。对苯达松的降解发现,与其他电极相比,Ti/TiO_(2)-RNTs/Sb-SnO_(2)/PbO_(2)-ND电极的催化活性更高、平均能耗更少。氯离子的存在可显著提升电催化氧化效率,10 mmol/L的Cl-可将COD的去除率从49%提升到69%。此外,Ti/TiO_(2)-RNTs/Sb-SnO_(2)/PbO_(2)-ND电极有着良好的催化稳定性和较长的使用寿命。

A new Ti/TiO_(2)-RNTs/Sb-SnO_(2)/PbO_(2)-ND electrode is prepared by electrodeposition technique using electrochemically reduced titanium dioxide nanotubes and nano-diamond as the interlayer and dopant,respectively.Results show that the crystals on the surface of the electrode are almostβ-PbO_(2) with grain size of 17 nm.Electrochemical analysis results show that the reduced titanium dioxide nanotubes and nano-diamond render PbO_(2) electrode with less charge transfer resistance,higher oxygen evolution overpotential and larger electrochemical active area.Degradation experiments for bentazon indicate that Ti/TiO_(2)-RNTs/Sb-SnO_(2)/PbO_(2)-ND electrode shows higher catalytic performance and less average energy consumption than other electrodes.It is also found that the removal efficiency of COD increases from 49%to 69%after 120 min treatment in the presence of 10 m M Cl-in the electrolyte.Recycle experiment and accelerated life test confirm that Ti/TiO_(2)-RNTs/Sb-SnO_(2)/PbO_(2)-ND electrode has good stability and long service life.