Comparative electrochemical study of self-assembled monolayers of 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, and 2-mercaptobenzimidazole formed on polycrystalline gold electrode

摘要: Abstract Comparative electrochemical behavior of self-assembled monolayers (SAMs) three heteroaromatic thiols, 2-mercaptobenzoxazole (MBO), 2-mercaptobenzothiazole (MBT), and 2-mercaptobenzimidazole (MBI) are investigated by means cyclic voltammetry impedance spectroscopy (EIS). The characteristics the electrode/solution interface considerably differently affected thiols constructing SAMs. consumed charges for reductive desorption SAMs, which is criterion amount chemically adsorbed thiol, significantly different these specially MBT, implying that SAM MBT formed through both sulfur atoms; thiol skeleton thiazole ring. Desorption potentials SAMs have shown following order strength gold–sulfur bond: MBT > MBO > MBI. Activity as pH-sensitive interfaces was also their surface-p K a values derived from EIS measurements showed this acidic SAMs: MBO > MBT > MBI. This same expected due to difference in electronegativity O, S, N heteroatoms, confirms most electron-rich ring imidazole attached benzene MBI. A comparison interfacial charge transfer resistance variation function gold immersion time solution reveals kinetics Au–MBT assembly those two others formation via atoms MBT.