以制备的氨基化碳纳米管负载铁铈(NCNTs-Fe/Ce)作为阴极的电芬顿法去除水中的甲基橙(MO)。研究显示,当NCNTs-Fe/Ce中的Fe/Ce摩尔比=2∶1、电流密度30 mA/cm²、pH 3~9、反应90 min时,初始浓度100 mg/L的MO去除率可达88.3%以上,其中pH 6.8(不调pH)时MO的去除率达到98.7%;与相同条件下NCNTs-Fe阴极的电芬顿法(MO去除率80.6%)比较,阴极上Ce的加入促进了铁铈间的氧化还原,显著提高了MO的去除效率。表征结果显示,铁和铈成功负载于NCNTs上,该材料表面存在着酰胺、羰基等多种基团。NCNTs-Fe/Ce阴极还具有良好的稳定性,重复使用10次后,对MO的去除率仍达到92.9%。进一步的淬灭实验发现,单线态氧(¹O₂)是起主要作用的活性基团。

Methyl orange is removed from water by an electric Fenton method using the prepared aminoated carbon nanotubes-supported iron-cerium (NCNTs-Fe/Ce) as cathode.Results show that the removal rate of methyl orange at an initial concentration of 100 mg·L^-1 can exceed 88.3% in 90 min of reaction when the molar ratio of Fe/Ce in NCNTs-Fe/Ce is=2∶1,the current density is 30 mA·cm^-2,and pH in the range of 3-9.Especially,the removal rate of methyl orange reaches 98.7% at a pH of 6.8 (without pH adjustment).Under the same conditions,the removal rate of methyl orange is 80.6% only by the electric Fenton method driven by NCNTs-Fe cathode.The addition of Ce on the cathode promotes the redox between cerium and iron,and significantly improves the removal efficiency of methyl orange.The characterization results show that both iron and cerium are successfully loaded on NCNTs,and there are various groups such as amide and carbonyl groups on the surface of the material.NCNTs-Fe/Ce cathode also has good stability,by which the removal rate of methyl orange still reaches 92.9% after 10 repeated uses.Further quenching experiments show that singlet oxygen (¹O₂) active group plays the main role.