Invention of polarography

Since the invention of polarography in 1922, more than 30,000 papers dealing with this technique have been published. Since more than 90% of those papers deal with practical applications, any choice of examples cannot be more than an indication of the possibilities the method offers. The following selection, which is necessarily subjective, was made with the aim of showing applications in a variety of fields. 

The first example is the measurement at a mercury (Hg) electrode. After the invention of polarography, an enormous body of work on the adsorption of organic molecules has been made at a mercury electrode surface. However, mercury is a liquid metal and its hanging drop changes its shape in response to the change of the surface tension, thus to the electrode potential. It is a difficult task to measure the reflection change at a mercury drop electrode surface, since exclusion of the perturbation due to the change of the shape of the electrode is critical. 

The invention of polarography by Heyrovsky in 1920 s as a new experimental method followed by detail theoretical treatment in 1930 s which led to quantitative interpretation of the polarographic current-potential transients marked a milestone in electrochemistry (8,9). This technique permitted the electrochemist to interpret mass transfer electrode processes in terms of diffusion or convection it was subsequently applied in studies of reaction kinetics. Although the technique was limited to dropping mercury electrodes, its impact on electrochemistry and development of novel electroanalytical techniques was so tremendous that the inventor was awarded a Nobel Prize in Chemistry in 1959. 

Since the invention of d.c. polarography [10, 11], numerous inorganic and organic compounds have been studied by means of this method in Heyrovsky s school and extensive knowledge gathered about the electrochemical properties of these compounds. Among them, many cases were discovered where the polarographic wave appeared to be influenced by the existence of chemical equilibria between the electroactive substance and other, in most cases electroinactive, species in the electrolyte solution, more particularly by the finite rate at which these equilibria relax after the electrochemical perturbation. In fact, the chemical reaction serves as either a source or a sink to deliver or to consume the electroactive reactants and products, in addition to diffusion. 

The results were summarized by Fichter in his useful book Organische Elektrochemie in 1942. This development took place along with the invention of new electroanalytical techniques for the study of electrode processes, for instance, polarography at the dropping mercury electrode introduced by Heyrovsky in the early 1920s. Other important contributions were made by Lingane, Kolthoff, Laitinen, and Delahay. 

Nobel Prize in chemistry for his discovery and development of polarography. His invention of the polarographic method dates from 1922, and he concentrated the remainder of his career on the development of this new branch of electrochemistry. He died in 1967. 

Polarography was invented by Jaroslav Heyrovsky 53 years ago. Since that time, it has spread into many fields of research and practical analysis simultaneously, it developed as a method and its instrumentation reached a high level [1,2], Biochemistry and pharmacy belong to the disciplines where polarography plays a significant role, particularly as an analytical method [3-7]. 

In 1922 he invented the polarographic method in electrochemistry (polarography is based on electrolysis using a dropping mercury electrode), and he continued development of this new branch of electrochemistry for decades. In 1926 he married Marie Koranova and had two children. In 1950 he was appointed director of the newly established Polarographic Institute (incorporated into the Czechoslovak Academy of Sciences in 1952). In 1959 he was awarded the Nobel Prize in chemistry for his discovery and development of the polarographic methods of analysis. ... 

Jaroslav Heyrovsky (1890-1967) invented polarography and the use of the dropping mercury... 

The most original working electrode contains an active mercury micro-dropper. The voltammetric technique making use of this electrode is called polarography, invented by Heyrovsky in the 1920s. 

Polarography, invented in 1922 by Czech electrochemist J. Heyrovsky, was in the period 1930 up to the end of the 1950s the worldwide commonly used electroanalytical method. In its classic form it represents a special case of linear sweep voltammetry characterized by the use of the dropping mercury electrode (DME). The linear voltage scan applied to the electrolytic cell is slow (typically 0.1 V up to 0.4 V min ). With regard to the usual mercury drop-life (1 -4 s) the fundamental assumption can be accepted that each single drop is polarized at nearby constant potential. 

At one time polarography was the most widely used analytical technique in the world. Variants, particularly of wave-form, have been invented. However the technique has been supplemented and in many cases replaced by cyclic voltammetry which gives reduction (and oxidation potential) and, at the same time, information on the rapidity (reversibility) of the electron-transfers, i.e., on the kinetics of the reactions. In this area seminal work was done by Nichols and Shain both then at the University of Wisconsin. 

Mercury has been widely used in electrochemistry, especially as a working electrode due to its unique electrochemical properties. The employment of a mercury electrode as the working electrode is called polarography, which was invented by Professor Jaroslav Heyrovsky in 1922 [1], Prof. Heyrovsky was awarded Nobel Prize in 1959 for the significance polarography has estabhshed in electrochemical analysis. In this entiy, we will introduce different types of mercury drop electrodes, the associated techniques for utilizing mercury electrodes, and the applications of mercury electrodes for the determination of various species. 

In spite of several drawbacks which arise from the application of mercury as an electrode material (limited anodic range, chemical reactivity and toxicity, difficult handling etc.), mercury electrodes are widely used. The reason, apart from their extensive cathodic range of polarization is that they enable the utilization of a huge amount of experimental material, collected since polarography was invented. 

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