Modification of gold electrode by self-assembled 2-mercapto benzothiazole for the determination of Hg²⁺

Abstract

An electrochemical method was developed for the determination of mercury using polycrystalline gold electrode modified by self-assembled monolayers (SAMs) of 2-mercaptobenzothiazole (MBTH). Morphological and electrochemical characterisation of the self-assembled structure of MBTH was performed using atomic force microscopy (AFM) and electrochemical impedance spectroscopy (EIS) measurements. The monolayer of MBTH has shown high affinity for Hg²⁺. The limit of detection for the determination of Hg²⁺ using the MBTH SAMs modified gold electrode was obtained as 0.421 μg L⁻¹. The pre-concentration of Hg²⁺ at open circuit potential is beneficial for the onsite monitoring of mercury concentration in water samples.

Keywords:

• self-assembled monolayes (SAMs)
• gold electrode
• 2- mercapto benzothiazole
• mercury
• stripping voltammetry