Standard states and standard adsorption gibbs energy of substances at electrode interfaces

Electrochemical behaviour of benzylamine, 2-phenylethylamine and 4-hydroxyphenylethylamine at gold. A comparative study

“…Taking as the reference state the unit mole fraction of amine in the bulk of the solution and a monolayer coverage (H = 1) of the non-interacting adsorbate molecules at the surface [21,24,[57][58][59][60], b is related to the standard Gibbs energy of adsorption DG 0 ad by the following relationship: b ¼ ½ð1=55:5Þ expðÀDG 0 ad =RTÞ. The corresponding values of DG 0 ad change in the sequence: benzylamine (DG 0 ad = -40.0 ± 0.05 kJ mol -1 [61]) \phenylethylamine (DG 0 ad = -42.7 ± 0.04 kJ mol -1 ) \tyramine (DG 0 ad = -46.0 ± 0.06 kJ mol -1 ), reflecting the stronger interaction between the amine molecule and the electrode surface.…”

Modern Electrochemistry 2A

“…Standard states of species adsorbed on the surface and in solution have been given a lot of thought by scientists in the area (Conway, 1974;Nikitas, 1984;Trasatti, 1987). The importance of finding convenient standard states is that in doing so we are able to compare the adsorption energies of different adsorption processes calculated by different isotherms.…”

Theory of interfacial potential differences: effects of adsorption onto hydrated (gel) and nonhydrated surfaces

“…For aromatic amines adsorbed to mercury, AGC°r anges from -5.2 kcal/mol for pyridine to -8.2 kcal/mol for 2,3-dimethylaniline (42). Butoxyethanol and hexanol have AGC°v alues for adsorption onto mercury of -5 and -6 kcal/mol, respectively (43). A value of-2.13 kcal/mol can be derived from data presented in ref 22 for the adsorption of iodide onto mercury.…”