稀土Ce掺杂Ti/Sb-SnO2电极的电化学性能及应用

采用热分解法制备Ti/Sb-SnO2电极和Ti/Sb-SnO2/Ce电极,采用扫描电子显微镜(SEM)、X射线衍射(XRD)仪和电化学实验技术对电极的表面形貌、物相组成和电化学性能进行表征。结果表明:Ti/Sb-SnO2电极表面形成了SnO2晶胞,经稀土Ce改性后SnO2晶粒明显细化,SnO2衍射峰强度变强且峰形宽化。Ti/Sb-SnO2/Ce电极峰电流值最大、表面稳定性增强和催化活性明显提高。在最佳工艺条件下,Ti、Ti/Sb-SnO2和Ti/Sb-SnO2/Ce电极对橙黄G目标污染物的去除率分别为46.6%、61.9%和94.9%,且降解过程均符合一级反应动力学模型,速率常数分别为0.0289、0.0633、0.1971min-1,Ti/Sb-SnO2/Ce电极的速率常数分别是Ti/Sb-SnO2电极的3倍,Ti电极的7倍,表明在电极表面涂层中掺杂稀土元素Ce可有效提高电极的性能。

Electrochemical Performance and Application of Ce Doped Ti/Sb-SnO2 Electrodes

The Ti/Sb-SnO2 electrode and Ti/Sb-SnO2/Ce electrode were prepared by thermal decomposition. The surface morphology, phase composition and electrochemical performance of the electrodes were analyzed by SEM, EDS, XRD and CHI. Results show that SnO2 crystal cells form on the surface of the Ti/Sb-SnO2 electrode, while SnO2 grains are refined obviously due to the Ce modification and SnO2 diffraction peaks becomes stronger and broader. The Ti/Sb-SnO2/Ce electrode has the largest peak current and its surface stability and catalytic activity are enhanced greatly. Under the optimal conditions, the removal rates of orange G by Ti/Sb-SnO2/Ce, Ti/Sb-SnO2 and Ti electrodes are 94.9%, 61.9% and 46.6%, respectively, and the degradation processes follow first order reaction kinetics. The rate constants of Ti/Sb-SnO2/Ce, Ti/Sb-SnO2 and Ti electrodes are 0.1971, 0.0633 and 0.0289 min-1, respectively. The rate constant of Ti/Sb-SnO2/Ce electrode is three times of that of Ti/Sb-SnO2 electrode and seven times of that of Ti electrode. Therefore, the electro-catalytic oxidative characteristic of Ce modified Ti/Sb-SnO2 electrode is the best.