Potentiometric and voltammetric

Fifield, F. W. and Kealey, D., Principles and Practices of Analytical Chemistry, International Textbook Company, Edgeware, UK, 1975. A trusted work-horse of a text. It is showing its age a bit now, but is an excellent first look at analytical chemistry. Its compare and contrast style of potentiometric and voltammetric analyses is widely copied, it seems. 

Crow, D. R., Principles and Applications of Electrochemistry, 4th Edn, Blackie Academic, Glasgow, 1994. This text has quite a long history now (first published in 1974). It is pleasure to read and is therefore recommended highly, both for potentiometric and voltammetric study. Some of its examples and self-assignment questions are ideal practise material. 

An interesting issue, in the field of nonspecific analysis, is the fusion of data coming from different analytical techniques. As for artificial tongues, potentiometric and voltammetric data have been employed... 

With respect to the type of sensors that can be used in an electronic tongue, practically all the main families of chemical sensors have been used to form the sensor array, viz. potentiometric, voltammetric, resistive, gravimetric and optical, if main sensor families have to be quoted [11], Table 30.1 sketches a survey of different approaches that can be recorded when the specialized literature is inspected. Even hybrid systems have been proposed, mainly those combining potentiometric and voltammetric sensors [3,12], The combination of electronic noses and electronic tongues to improve detection or identification capabilities, in a sensor fusion approach, has also been proposed [13,14],... 

Thus the range of applications is vast. Electroanalysis, potentiometric and voltammetric industrial electrolysis, electroplating, batteries, fuel cells, electrochemical machining, and many other related applications, including minimization of corrosion biosensors and bioelectrochemistry. 

E° and 1/2 values of Cd +/Cd couple and Cd complexes in aqneous solntion have been measured through potentiometric and voltammetric methods (Table 4). Few data are available... 

Potentiometric and voltammetric titrations and assumed 1 1 metal/fulvate mole ratio in the complex. ... 

Interfaces between two immiscible solutions with dissolved electrolytes, which are most interesting to workers in several disciplines, cover theoretical physical electrochemistry and analytical applications for sensor design. These interfaces are used in interpretation of processes that occur in biological membranes and in biological systems. The interface between two immiscible electrolyte solutions was studied for the first time at least 100 years ago by Nemst (I), who performed the experiments that provide the theoretical basis for current potentiometric and voltammetric studies of interfaces. In 1963, Blank and Feig (2) suggested that an interface between two immiscible liquids could be used as a model (at least as a crude approximation) for... 

Figure 2. Apparatus used for potentiometric and voltammetric studies on the interface between two immiscible electrolyte solutions. (Reproduced from reference 4. Copyright 1990 American Chemical Society.)...

The influence of chloride ions on the behaviour of copper(II) sulphide electrode was studied by using potentiometric and voltammetric methods in four different media 1X10 " M HNO3, 1x10-2 M HCl, 1x10-2 M HCl + 1 M KCl and 1 M HCl. The potentiometric calibration curves obtained in diluted acids are similar to those reported above (Fig.4, curves 1,2), indicating no difference in the mechanism of copper(II) sulphide electrode action. 

In addition to these approaches, there have been some attempts to monitor immunological reactions directly using both potentiometric and voltammetric methods of analysis. In the early 1950 s, Breyer and RadclifF reported their results on the use of polarography to study the interaction of an azoprotein with a specific antiserum raised in a rabbit. In the presence of non-specific antisera, no decrease (other than that due to a diluent effect) was seen in the polarographic wave due to the antigen. A sharp decrease in this signal was noted, however, when the specific antiserum was added to the cell. 

Electrochemical methods for chemical analysis can be divided into two types potentiometric and voltammetric. Potentiometric measurements are made under conditions where no current flows i.e. the potential of the test electrode is measured against that of a suitable reference electrode. 

Cassir, M., Chauvaut, V., Alfarra, A., and Albin, V. (2000) Study of cerium species in molten LijCOj-NajCOj in the conditions used in molten carbonate fuel cells. Part II potentiometric and voltammetric behaviour. J. Appl. Electrochem., 30,1415. 

A non-polarizable electrode with a known and highly reproducible potential used for potentiometric and voltammetric analyses. See also calomel electrode. 

Zanganeh AR, Amini MK (2007) A potentiometric and voltammetric sensor based on polypyrrole film with electrochemically induced recognition sites for detection of silver ion. Electrochim Acta 52 3822-3830... 

The question of the nature of the oxygen electrode in molten nitrates has been quite recently reopened by Temple and co-workers,who state that potentiometric results at platinized electrodes are in agreement with the reaction + 2e 0. These results imply a greater stability for the oxide ions in molten nitrates than that arising from the studies of Zambonin and Jordan.It appears that further work will be needed to resolve this controversy. One reason for the discrepancy between potentiometric and voltammetric (chronopotentiometric) results in nitrates may be the different electrochemical behavior of platinized (used for potentiometric work) and bright (used for voltammetric studies) platinum. 

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