An electrochemical sensor based on the three-dimensional functionalized graphene for simultaneous determination of hydroquinone and catechol

•The 3D functionalized graphene modified electrode (3DFG/GCE) is prepared.•The 3DFG/GCE can simultaneously detect hydroquinone (HQ) and catechol (CC).•The developed method can determine HQ and CC in real water samples.

In this study, a simple and sensitive electrochemical analytical method is developed for simultaneous detection of hydroquinone (HQ) and catechol (CC) employing the three-dimensional functionalized graphene (3DFG) modified glass carbon electrode (GCE). The 3DFG modified electrode can distinguish between HQ and CC, with higher oxidation currents in comparison with bare GCE and two-dimensional graphene (Gr) modified electrode, showing the enhanced catalytic activity. The differential pulse voltammetry (DPV) shows that the isomers can be detected sensitively and selectively at 3DFG/GCE with peak-to-peak separation about 100 mV. Under the optimized conditions, the oxidation peak current increases linearly with concentration of HQ ranged from 3.10 × 10−7 to 1.31 × 10−5 M and concentration of CC ranged from 2.50 × 10−7 to 1.29 × 10−5 M, respectively. The detection limits are 1.0 × 10−7 M and 8.0 × 10−8 M for HQ and CC (S/N = 3), respectively. Moreover, the proposed method has been successfully applied to the simultaneous determination of HQ and CC in real water samples with satisfactory recoveries.

Graphical abstractA simple and sensitive electrochemical method for the simultaneous and quantitative detection of hydroquinone (HQ) and catechol (CC) was developed, based on a three-dimensional functionalized graphene (3DFG) modified glass carbon electrode (GCE). The 3DFG modified electrode could well distinguish HQ and CC simultaneously with the peak separation up to 100 mV, which displayed higher catalytic activity in comparison with bare GCE and two-dimensional graphene (Gr) modified electrode.Figure optionsDownload full-size imageDownload as PowerPoint slide