Electrochemical contributions: Gustav Theodor Fechner (1801–1887)

Gustav Theodor Fechner (Figure 1) was a German physicist, psychologist, and philosopher. His scientific contributions were mostly in the area of experimental psychology. He was a founder of psychophysics and he is particularly credited for discovering the non-linear relationship between psychological sensation and the physical intensity of a stimulus. However, for the purpose of this historical note, his contribution to electrochemistry must be emphasized.

Fechner extensively performed electrochemical experiments, particularly testing Ohm's law for electrolyte solutions in galvanic cells. He was the first to introduce into electrochemical science the parameter of the charge transfer resistance at an electrode/electrolyte interface. This factor is highly important for electrochemical kinetics in modern electrochemistry. Fechner was the first who reported in 1828 the observation of electrochemical oscillations during the anodic dissolution of nickel in nitric acid (Figure 2A). From that time, numerous systems with non-stationary oscillating behavior have been discovered.

Fechner designed an electroscope (electrometer) with improved sensitivity. This instrument consisted of 800 to 1000 pairs of metal foils charging two metal condenser plates. A thin strip of gold foil was hung between these plates (Figure 2B). A deviation of the gold foil from its vertical position was used for sensing an electric charge on it with very high sensitivity.

Fechner was very influential by translating and completely rewriting volume 3 (Lehrbuch des Galvanismus und der Elektrochemie) of Jean Baptiste Biot's textbook on experimental physics in which he gives a full account of the state of knowledge in electrochemistry of his time, including his findings.

This article is part of a series featuring historic contributions in and around electrochemistry. At least one such article appears in every issue of Electrochemical Science Advances.

The author declares no conflict of interest.