Effect of Traces of Large Molecules Containing Nitrogen on Hydrogen Overvoltage

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Science  23 Oct 1964:
Vol. 146, Issue 3643, pp. 521-523
DOI: 10.1126/science.146.3643.521


Organic amines, present in very small concentrations (below 10-6 M) in 0.1N H2SO4, cause a significant increase in hydrogen overvoltage, the effect being stronger the higher the molecular weight. The increase could be accounted for by the usual site-blockage concept. In the case of egg albumin, a drastic increase of over 300 mv was observed at 12.5 ma/cm2 for a concentration of only 0.01 part per million. A new mechanism is proposed in which the dielectric constant and hydrogen-ion activity are believed to be depressed in a region twice as thick as the usual transition region.