Microwave-assisted synthesis of Bi2WO6 flowers decorated graphene nanoribbon composite for electrocatalytic sensing of hazardous dihydroxybenzene isomers

A microwave-assisted synthesis is described for the preparation of bismuth tungstate/graphene nanoribbons (Bi2WO6@GNRs) nanocomposite as cost-effective alternative to existing hydrothermal method. HR-TEM, XRD, XPS, EDX, BET and Raman characterizations reveal the incorporation of Bi2WO6 flowers on GNRs. The electrochemical and interfacial properties of the composite were probed by voltammetry and impedance studies. The electrocatalytic ability of the composite was assessed by studying the redox reactions of hazardous dihydroxybenzene isomers. Bi2WO6@GNRs modified screen-printed electrode was found to distinguish the voltammetric signals of catechol and hydroquinone (separation gap of 140 mV, vs. AgIAgCl), minimizes reaction over potentials, and amplifies the electrochemical current signal. The effects of concentration scan rate and cross reactivity are studied. Bi2WO6@GNRs incorporated sensor displayed detection limits of 5.31 nM and 7.24 nM for catechol and hydroquinone, respectively. The method was found to be practically applicable in the determination of catechol and hydroquinone in water samples and face cream sample, respectively.