Spectroelectrochemistry conducting polymer

Feb. 28,1934, Camden, NJ, USA - Mar. 3,2003, Cincinnati, OH, USA) Mark received a B.A. in chemistry from the University of Virginia and a Ph.D. from Duke University. He was postdoc at the University of North Carolina and at the California Institute of Technology. After a faculty position at the University of Michigan he served from 1970 until his death as Professor in the Chemistry Department of the University of Cincinnati. Mark was electrochemist and analytical chemist. His major contributions concern spectroelectrochemistry and conducting polymer electrodes. He was among the pioneers of kinetic methods of analysis. His scientific work is documented in over 300 publications and 14 books which he either has written or edited. 

Thin-film electrode — An electrode covered with a thin film of a given substance. The purpose of placing a thin film on the electrode surface is to obtain desired electrode properties. Many different substances have been used to prepare film electrodes they include among others mercury (see - thin mercury film electrodes) gold, boron-doped diamond (see - boron-doped diamond electrode), conductive polymers (see - polymer-modified electrode), and alkanethiols. The film thickness can vary from several micrometers (mercury) to monomolecular layers (thiols). In some cases (e.g., for - spectroelectrochemistry purposes) very thin layers of either gold or tin oxide are vapor-deposited onto glass plates. Thin film electrodes are often called - surface-modified electrodes. 

Spectroelectrochemistry and Spectroscopy of Conducting Polymers M. Zagorska, A. Pron and S. Lefrant... 

R. Holze, Spectroelectrochemistry of Conducting Polymers, in Handbook of Electronic and Photonic Materials and Devices, vol. 8, ed. by H.S. Nalwa (Academic Press, San Diego, 2000), p. 209... 

Spectroelectrochemistry is one of the many facets of photoelectroanalytical chemistry. It can be used for numerous purposes in solving the mechanisms of electrochemical processes but especially with electrically conducting polymers it shows its main advantages. The original drive to study conductive polymers arose from the applications anticipated in the energy storage, but these polymers are also interesting from the analytical point of view as potential sensor materials. 

Today, UV-visible spectroelectrochemistry has become an essential tool in the study of redox processes, particularly when the processes are reversible and the reagents or products of electrolysis are colored. For example, the technique is of enormous value in the study of the electrochemistry of porphyrins and ph-thalocyanines, though it took some time to catch on. A review of porphyrin electrochemistry from 1986 barely mentions the technique, now an essential, even routine, tool in this field [4]. Another area of chemistry in which spectroelectrochemistry has been extremely important is conducting polymers, a field that had barely started 20 years ago. Spectroelectrochemistry has also been developing rapidly as the technology of electronic and optical detection has advanced. For example, we shall see later how time-resolved spectroelectrochemistry is now able to provide a wealth of information about electrochemical processes. 

Ferraris, J.P, C. Henderson, D. Torres, and D. Meeker. 1995. Synthesis, spectroelectrochemistry and application in electrochromic devices of an n- and p-dopable conducting polymer. Synth Met 72 147-152. 

By recording simultaneously the electric current and the absorption spectrum of a thin film of conducting polymer, a wealth of information on the characteristics of material is obtained. The methods of spectroelectrochemistry in connection with conventional electrochemistry in solution have been known for a long time. The measurement can be carried out in different ways. 

From the description of the setup, it is clear that techniques working with external reflection require reflecting electrodes. The major type used is bulk metal electrodes, either as polycrys-talline material or as single crystals. However, other reflecting electrode materials like glassy carbon may be used as well. These electrodes may either serve as system under smdy or simply as substrates, onto which the sample of interest (e.g., a conducting polymer) is deposited. Approaches where nanoparticles or carbon supported catalysts are deposited onto such electrodes and investigated with IR spectroelectrochemistry have been described as well (e.g., [11]). 

---