十二烷基硫酸钠对IrO_2-Ta_2O_5/SnO_2-Sb-MnO_2/Ti电极电催化性能的影响

Effect of Sodium Dodecyl Sulfate (SDS) on Electro-Catalytic Performances of IrO_2-Ta_2O_5/SnO_2-Sb-MnO_2/Ti Electrode

采用涂刷-热分解法制备不同浓度阴离子表面活性剂十二烷基硫酸钠(SDS)的IrO_2-Ta_2O_5/SnO_2-Sb-MnO_2/Ti电极。通过扫描电子显微镜(SEM)和X射线衍射仪(XRD)对其微观形貌及物相组成进行分析;应用循环伏安、极化等测试手段,表征制备电极的电催化活性。结果表明,适量添加十二烷基硫酸钠能够改善IrO_2-Ta_2O_5/SnO_2-Sb-MnO_2/Ti电极的微观形貌,提高电催化活性。在本实验条件下,SDS最佳添加量是1.6 g/L,结晶化度高达99.83%。利用苯酚电催化降解实验和强化寿命测试进一步考察所制电极的电催化活性与稳定性,结果显示,在电流密度15 mA/cm^2条件下电解180 min,SDS的加入使苯酚去除率由原来的68.5%提高到79.2%,COD去除率由60.1%提高到67.5%,电催化性能得到提升,电极强化寿命由52 h延长至68 h。

An anionic surfactant, sodium dodecyl sulfate（SDS） was employed for preparation of the IrO_2-Ta_2O_5/SnO_2-Sb-MnO_2/Ti electrodes through the pyrolysis process. The microstructure and phase composition of the electrodes were analyzed via scanning electron microscopy（SEM） and X-ray diffraction（XRD）, and the cyclic voltammetry（CV） and polarization curves were also measured to evaluate their electro-catalytic activity by an electrochemical station（type CS310）. The results reveal that the employment of the SDS could effectively improve the microstructure as well as enhance the electro-catalytic ability of the electrodes. Under the conditions of this study, the optimum dosage of SDS is 1.6 g/L for preparation of the IrO_2-Ta_2O_5/SnO_2-Sb-MnO_2/Ti electrodes and the crystallization degree as high as 99.83% could be obtained. The electrode performances and stability were further investigated by anodic oxidation of phenol and accelerated life test. The experimental data depicts the phenol and chemical oxygen demand（COD） removal efficiency increase from 68.5% and 60.1% to 79.2% and 67.5% when electrodes without and with dosage of 1.6 g/L are used, respectively, for phenol degradation at conditions of current density of 15 mA/cm^2 and reaction time of 180 min; moreover, the accelerated life rises to 68 h, which is much longer than that of the former（52 h）.