Simultaneous and Highly Sensitive Determination of Hydroquinone and Catechol Using Carboxyl Functionalized Graphene Self-Assembled Monolayers

Carboxyl functionalized graphene (CFG) self-assembled monolayers (SAMs) were constructed on the carboxylated glassy carbon electrode based on covalent interaction for simultaneous determination of hydroquinone (HQ) and catechol (CC). Scanning electron microscopy and electrochemical impedance spectroscopy results proved that the CFG SAMs was successfully formed with enhanced conductivity. According to electrochemical voltammetry experiments, the modified electrode showed excellent sensitivity and selectivity for HQ and CC. Under optimal conditions, the sensing platform showed wide linear response for HQ and CC with detection limit of 0.2 mM (S/N=3) and 0.6 mM (S/N=3), respectively. Moreover, the sensor also displays good reproducibility and stability.