Electrosorption of phenol in aqueous solution using a plasma-activated CNT/TiO2 electrode
【Abstract】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.
【Keywords】 plasma-activation; CNT/TiO2 electrode; phenol; electrosorption; plasma-activation; CNT/TiO_2 electrode; phenol; electrosorption;
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