Electrodes modified with bismuth, antimony and tin precursor compounds for electrochemical stripping analysis of trace metals (a short review)

Abstract

Over the last decade, intensive research is being carried out towards the development of “green” electrochemical sensors. Bismuth, antimony and tin electrodes have been proposed as potential substitutes of mercury electrodes in electrochemical stripping analysis of trace metals. The main advantage of these metals as electrode materials is their lower toxicity compared to mercury. Among the different configuration of bismuth, antimony and tin electrodes, one of the most attractive involves the modification of a support material with a bismuth, antimony or tin precursor compound (oxide, hydroxide or sparingly soluble salt). When the electrode is polarized to a sufficiently cathodic potential, the metal precursor is reduced to the respective metal which forms a thin “film” on the surface of the support material. The present article is an overview of the existing state–of–the–art in the field of bismuth, antimony and tin precursor–modified sensors. This review covers and critically discusses the various fabrication approaches (support materials, types of precursor compounds, modification approaches, precursor reduction methods) and also lists typical applications of these precursor–modified sensors to electrochemical stripping analysis of metals.