铈锆复合氧化物修饰电极的制备及用于水样中Pb^(2+)的检测

Preparation of Cerium Zirconium Composite Oxide Modified Glassy Carbon Electrode and the Detection of Pb^(2+) in Water Samples

铅是一种有毒重金属,广泛分布在自然界中,会影响生态环境以及损害人体健康,因此对铅离子的检测十分必要。采用水热法制备了Ce_(2)Zr_(2)O_(7.04)纳米复合材料,将其滴涂在玻碳电极上制成修饰电极。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和X射线光电子能谱(XPS)分别对材料的组成、形貌、价态进行了表征。使用方波阳极溶出伏安法(SWASV)对Pb^(2+)进行检测,发现该修饰电极对Pb^(2+)具有良好的电流响应,同时对缓冲溶液、除氧时间、富集电位和pH值等条件进行了优化。结果表明,在优化的测试条件下,该修饰电极对Pb^(2+)的检测线性范围为0.0025~3.5μmol/L,检测限(LOD)(3S/N)为0.198 nmol/L,回收率在97.6%~104.4%之间。应用于水样中Pb^(2+)的检测表现出良好的重现性、稳定性和抗干扰能力,为水样中Pb2+的检测提供了一种新的方法。

Lead is a toxic heavy metal which is widely distributed in nature and affects the ecological environment and human health.Therefore,it is of significance to detect lead ions in the environment.In this paper,a modified glassy carbon electrode is fabricated by Ce_(2)Zr_(2)O_(7.04)nanocomposites that are prepared by the hydrothermal method.Scanning electron microscope(SEM),X-ray diffractometer(XRD)and X-ray photoelectron spectroscopy(XPS)are used to characterize the composition,morphology and valence state of the as prepared materials.Square wave anodic stripping voltammetry(SWASV)is applied to detect Pb^(2+),and it is found that the modified electrode has a good current response to Pb^(2+).Meanwhile,the examined conditions such as buffer solution,deoxidization time,enrichment potential and pH are optimized.The results show that the linear range of Pb^(2+) is 0.0025~3.5μmol/L,the detection limit(LOD)(3S/N)is 0.198 nmol/L,and the recovery rate is between 97.6%and 104.4%under the optimized test conditions.The method used in the determination of Pb^(2+) in water samples manifests good reproducibility,stability and anti-interference ability,which provides a new method for the detection of Pb^(2+) in water samples.