Cu-Co-Al类水滑石的制备及其电催化还原硝酸盐研究

通过共沉淀法制备不同摩尔比的Cu-Co-Al类水滑石化合物,采用X射线衍射、场发射扫描电子显微镜对类水滑石物质进行表征。结果表明,Cu、Co、Al摩尔比即n(Cu~(2+)):n(Co~(2+)):n(Al~(3+))=2:1:1、1:2:1、1:1:2和1:1:1时均能形成结构良好的水滑石类化合物。将所制备的材料制成涂膜电极,利用线性伏安扫描法研究其电催化还原硝酸盐的效果,结果表明n(Cu~(2+)):n(Co~(2+)):n(Al~(3+))=2:1:1时电催化还原硝酸盐效果最好,其还原峰电流与硝酸盐浓度及扫描速率呈正相关。研究结果表明,Cu-Co-Al类水滑石涂膜电极可以用于硝酸盐的电化学检测与去除工艺过程中。

Research on the synthesis of Cu-Co-Al hydrotalcite-like compounds and its electrocatalytic reduction of nitrate

In this study, Cu-Co-Al hydrotalcite-like compounds with different molar ratios were prepared by co-precipitation method, and then characterized by X-ray diffraction (XRD) and emission scanning electron microscope (SEM). Experimental results showed that hydrotalcite-like compounds were successfully synthesized under four molar ratios of n(Cu²⁺):n(Co²⁺):n(Al³⁺)=2:1:1, 1:2:1, 1:1:2, and 1:1:1, respectively. The as-prepared hydrotalcite-like compounds were used as coating electrode for the electrocatalytic reduction of nitrate. The results of linear sweep voltammetry (LSV) showed that the highest electrocatalytic activity was achieved at the molar ratio of n(Cu²⁺):n(Co²⁺):n(Al³⁺)=2:1:1. The peak currents had a positive relationship with both nitrate concentration and scan rates. This research suggested that the electrodes coated by Cu-Co-Al hydrotalcite-like compounds could be applied to the electrolytic detection or removal of nitrate from aqueous phase.