Adsorption of Tri‐n‐Butyl Phosphate (TBP) from NaClO₄ Aqueous Solution on Hg Electrode

Abstract

The adsorption of TBP on Hg electrode from aqueous NaClO 4 media has been studied using differential capacity and chronocoulometric measurements. TBP adsorbs in two steps, the first corresponding to a flat and second to a perpendicular orientation. Both orientations were observed in the entire investigated potential range. The maximal measured surface concentration (G max ) of TBP reaches a value of 1.55 Â 10 À10 mol cm À2 , which corresponds to the theoretical value for densely packed molecules in perpendicular orientation. G value of the first isotherm step plateau is about 7 to 15% smaller than G max and decreases strongly at potentials more negative than À 0.9 V due to the repelling of negative charges between the electrode and the phosphate group. The standard Gibbs energy of adsorption was found to reach the value of À 34 kJ mol À1 .

Adsorption of cetyltrimethylammonium bromide and/or cetyldimethylbenzylammonium chloride on partly covered hanging mercury drop electrode

“…The structure of adsorbates and the complexity of involved interactions between adsorbed molecules make the explanations of the results difficult [6,10]. The hanging mercury drop electrode (HMDE) has also been used as a model surface for the physicochemical study of adsorption of hydrophobic molecules [11][12][13].…”

Interfacial thermodynamics of gallic acid adsorption on a chargeable hydrophobic surface

“…However, a detailed thermodynamic study of the redox behaviour of GA at a well-controlled interface is still lacking. The hanging mercury drop electrode (HMDE) has been used as a model surface for the physicochemical study of adsorption of hydrophobic molecules [15][16][17]. In a recent work, the HMDE was used as a model surface for the cell membrane with regard to the surface activity of the adsorption of the drug mitomycin [18] and imidacloprid insecticide [19,20].…”

Electrochemical interfacial adsorption mechanism of polyphenolic molecules onto Hanging Mercury Drop Electrode surface (HMDE)

“…For example the Hanging Mercury Drop Electrode (HMDE) has been used as a model surface for the physicochemical study of adsorption phenomena of hydrophobic molecules such as aliphatic fatty acids [19], tri-n-butyl phosphate [20] and the study of fractal properties of adsorbed linoleic acid [21], to study surface adsorption of mitomycin [22], the insecticide imidacloprid [23,24]. Also, HMDE was previously used to study the mechanism of the reduction and breaking of the S-S bonds in proteins [25,26], dithiocarbamate pesticides [27] and cysteine [28,29], using Cathodic Stripping Voltammetry.…”