新型Nd掺杂PbO_2阳极性能及对AOII的电催化氧化作用

Performance of a Novel Nd-Doped PbO_2 Anode and Its Electro-Catalytic Oxidation Activity for the Degradation of Acid Orange II

采用电沉积法制备了稀土金属Nd改性Pb O_2电极(Nd-Pb O_2),并通过扫描电镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)、荧光光谱(FP)、线性极化扫描(LSV)、强化寿命测试(ALT)、循环伏安扫描(CV)等方法表征了其表面结构和电化学性能,探讨了对酸性橙II(AOII)的电催化氧化性能。SEM、XRD、XPS测试结果表明,Nd以Nd^(3+)形式掺杂进入电极镀层,同时对表面形貌、元素组成均有不同程度的改变,但不改变镀层表面的β-Pb O_2晶型;电化学性能测试表明,Nd掺杂可有效提高电极的析氧电位和稳定性;CV测试及AOII降解实验结果表明,Nd-Pb O_2电极对AOII还表现出直接氧化作用,电催化氧化AOII能力更强;FP分析表明,Nd-Pb O_2具有较强的催生羟基自由基能力,可增强电极降解有机物的催化活性。

A novel PbO_2 electrode doped with rare earth of Nd（Nd-PbO_2） was prepared by an electrodepositon technique. The microstructure and electrochemical properties of the doped electrode were investigated using scanning electron microscopy（SEM）, X-ray diffraction（XRD）, X-ray photoelectron spectroscopy（XPS）, fluorospectrophotometry（FP）, linear-sweep voltammetry（LSV）, accelerated lifetime（ALT） and cyclic voltammetry（CV）. SEM, XRD and XPS analyses reveal that the Nd-PbO_2 electrode is covered by β-PbO_2 with tetragonal crystal structure and the main chemical valence of Nd is （3＋）. The morphology and elementary composition of the electrode surface have changed at different degrees. Electrochemical performance tests show that Nd doping can increase oxygen evolution potential and stability of PbO_2 electrode. The results of CV and AOII degradation experiments indicate that Nd-PbO_2 electrode can enhance the direct anodic oxidation, which is helpful to mineralize AOII. Besides, the FP analysis reveals that the electrocatalytic activity of the Nd-PbO_2 electrode in the degradation of organic materials is higher than that of the PbO_2 electrode because more hydroxyl radicals can be generated on its surface.