Determination of pK a of benzoic acid- and p-aminobenzoic acid-modified platinum surfaces by electrochemical and contact angle measurements

Ali Osman SOLAK

Acidity constant values of benzoic acid (BA)-modified platinum electrode (Pt-BA) and p-aminobenzoic acid (pABA)-modified platinum electrode (Pt-NHBA) surfaces were determined using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and contact angle measurements (CAM). Diazonium tetrafluoroborate salt reduction and pABA oxidation reactions were used to prepare (Pt-BA) and (Pt-NHBA) surfaces, respectively. Both surfaces exhibited pH dependence with [Fe(CN)6]3−/4− redox probe solutions at different pH; this allowed us to estimate the surface pK a values. Acidity constants for ...Более