论文部分内容阅读
介绍一种应用ＰＶＣ膜修饰粉末微电极的溶出伏安法。该法不需镀汞，不需搅拌，且可在浓度很稀的支持电解质中富集。在浓度为０．０２ｍ ｏｌ／ＬＨＡｃ 介质中，进行阳极溶出伏安扫描，有一灵敏Ｐｂ 氧化峰出现，峰电位为－ ０．４５３ Ｖ（ｖｓ．ＳＣＥ），溶出峰电流与Ｐｂ２＋ 的质量浓度在５．０×１０－ ８ ～５．０×１０－ ６ｇ／ｍ Ｌ范围内有很好的线性关系，检出限为２．０×１０－ ８ｇ／ｍ Ｌ。该法应用于自来水和湖水中微量Ｐｂ２＋ 的直接测定，测定结果与悬汞电极（ＨＭＤＥ）一致。相对标准偏差（ｎ＝ ５）小于１．７％ ，加入回收率为９６．２％ ～９９．５％ 。
A kind of stripping voltammetry method using PVC membrane modified powder microelectrode is introduced. The method does not require mercury plating, does not require agitation, and can be concentrated in very dilute support electrolytes. In the concentration of 0.02mol / LHAc medium, anodic stripping voltammetry scan, there is a sensitive Pb oxidation peak appears, the peak potential of - 0.453 V (vs.SCE), the dissolution peak current and mass concentration of Pb2 + 5 .0 × 10-8 ~ 5.0 × 10-6g / m L range has a good linear relationship, the detection limit of 2.0 × 10-8g / m L. The method is applied to the direct determination of Pb2 + in tap water and lake water. The results are consistent with HMDE. The relative standard deviations (n = 5) were less than 1.7% and the recoveries were 96.2% ~ 99.5%.