吸附溶出伏安法对铑的痕量测定

Trace measurements of rhodium by adsorptive stripping voltammetry.

作者信息

Wang J, Taha Z

机构信息

Department of Chemistry, New Mexico State University, Las Cruces, NM 88003, U.S.A.

出版信息

Talanta. 1991 May;38(5):489-92. doi: 10.1016/0039-9140(91)80168-y.

DOI:10.1016/0039-9140(91)80168-y

PMID:18965175

Abstract

A sensitive stripping voltammetric procedure for quantifying rhodium is described. The complex of rhodium with chloride ions is adsorbed on the hanging mercury drop electrode, and the reduction current of the accumulated complex is measured during a negative-going scan. Cyclic voltammetry is used to characterize the interfacial and redox behaviors. The effect of pH, chloride concentration, accumulation potential and other variables is discussed. The detection limit is 1 x 10(-8)M ( approximately 1 ng/ml) with 5-min accumulation. A linear current-concentration relationship is observed up to 7 x 10(-7)M and the relative standard deviation (at the 2 x 10(-7)M level) is 3.0%. Possible interferences by co-existing metals are investigated.

摘要

本文描述了一种用于定量测定铑的灵敏溶出伏安法。铑与氯离子形成的络合物吸附在悬汞滴电极上，在负向扫描过程中测量积累络合物的还原电流。采用循环伏安法表征界面和氧化还原行为。讨论了pH值、氯离子浓度、积累电位和其他变量的影响。在5分钟积累时间下，检测限为1×10⁻⁸M（约1 ng/ml）。在高达7×10⁻⁷M的范围内观察到线性电流-浓度关系，相对标准偏差（在2×10⁻⁷M水平）为3.0%。研究了共存金属可能产生的干扰。