等离子改性CNT/TiO_2电极吸附去除水中苯酚的研究

利用电感耦合空气等离子体对涂覆法制备的CNT/TiO2复合电极进行射频放电改性处理.复合电极的表面形貌、润湿性及元素成分分别通过扫描电镜(SEM)、接触角测试仪、x射线光电子能谱(XPS)进行了表征.结果表明,改性后有利于苯酚吸附,电极比表面孔隙、亲水性、TiO2及含氧官能团均得以增加;循环伏安测试(CV)表明改性后电极比电容提高54%;改性后复合电极对苯酚的吸附量较改性前提高了45%.且等离子改性CNT/TiO2电极对苯酚的去除量随电压、苯酚初始浓度的增加而增加,吸附过程符合准二级动力学方程,吸附等温线符合Langmuir等温吸附模型.

Electrosorption of phenol in aqueous solution using a plasma-activated CNT/TiO2 electrode

The CNT/TiO2 composite electrode prepared by coating method was activated with radio frequency inductively coupled air-plasma. The surface morphology, wetting ability and surface elements of the plasma activated electrode were characterized by scanning electron microscopy (SEM), contact angle and X-ray photoelectron spectroscopy (XPS), respectively. It was found that the pore ratio, hydrophilic property, contents of TiO2 and oxygen containing groups on the surface of the electrode increased after the activation, which facilitated the adsorption of phenol. Cyclic voltammetry (CV) result indicated that its specific capacity also increased by 54% with the plasma treatment. Further, phenol removal efficiency for the activated electrode was enhanced by 45% compared to that of the raw electrode, and the removal of phenol increased as the increase of applied voltage and initial concentration. The adsorption process followed the pseudo-second-order kinetic model and the equilibrium adsorption isotherm well fitted the Langmuir model.