A surface network based on oxidative graphene oxide for the determination of hydroquinone and catechol in ground and wastewater samples

A sensing network based on oxidative graphene oxide (OGO) fabricated onto a glassy carbon electrode (GCE) by consecutive anodic treatment of a native synthesized surface materials called the virgin graphene oxide (VGO). The proposed oxidative step is crucial to decrease stacking interactions and enrichment the surface materials with oxygenated functionalities that play significant roles in improving the surface conductivity and electron transfer kinetics. A primary result achieved by electrochemical impedance spectroscopy (EIS) showed an exceptional reactivity of OGO-GCE interpreted by estimating the apparent rate constant (k_app) of electron transfer kinetics that approaches 8.7 times over VGO-GCE. The differential pulse voltammetry (DPV) experimental data for the simultaneous determination of hydroquinone (HQ) and catechol (CC) verify the remarkable reactivity of the OGO-GCE compared to both bare GCE and VGO-GCE. The above supportive evidences underlines the significance of abundant oxygen functional groups for fast kinetics at OGO surface materials. The selectivity test of OGO-GCE in the determination of HQ and CC under optimal conditions was excellently achieved at which the detection limit (DL_3σ) of HQ and CC were 0.114 μM and 0.124 μM, respectively. The successful analytical performance of OGO on two water samples suggested the application of robust, stable and promising materials for trace HQ and CC quantification.