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An electrochemical sensor based on carbon composites derived from bisbenzimidazole biphenyl coordination polymers for dihydroxybenzene isomers detection

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Abstract

Co-based coordination polymers (CoCP) based on 4,4′-bis(1H-benzo[d]imidazol-1-yl)-1,1′-biphenyl (BMB) ligand have been synthesized for the first time by the solvothermal method. The CoCP was carbonized at 700 °C under a nitrogen atmosphere to obtain carbide coordination polymer (C-CoCP) with a unique two-dimensional layered network structure. C-CoCP@GO was obtained by binding with GO and C-CoCP, its morphology and structure were investigated by XRD, SEM, EDS, FTIR, and TGA, which confirmed its two-dimensional stacked layered structure with high catalytic activity and large specific surface area. A highly sensitive electrochemical sensor was constructed for the simultaneous detection of hydroquinone and catechol based on the prepared carbon-based composite. Under optimized conditions, the working potentials (vs. Ag/AgCl) of HQ and CC are at 0.097 V and 0.213 V, respectively. The sensor exhibited an extremely wide linear range of 3–600 μM and 3–1750 μM for hydroquinone (HQ) and catechol (CC), respectively, with limits of detection (LOD) of 0.46 μM and 0.27 μM. The electrode material demonstrated stability over 14 days without significant attenuation of the response signal. Impressively, the sensor shows high stability, reproducibility, and selectivity due to the stable carbon skeleton structure of the C-CoCP material. In addition, it can be applied to the detection of hydroquinone in real samples with high interference immunity and high recovery. Hence, the C-CoCP@GO composite proved to be a great prospect and highly sensitive sensing platform for the detection of phenolic isomers.

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Acknowledgements

This work was supported by the Natural Science Foundation of China (U1608224 and 21671138), the China Scholarship Council (CSC, No. 202210340004 and CSC, No. 202210340005), and the General Fund of the Education Department Project of Liaoning Province (LJKZ0315).

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  1. China-Russian Institute of Engineering Materials Chemistry, School of Chemical Engineering, University of Science and Technology Liaoning, Anshan, Liaoning, 114051, People’s Republic of China

    Yan Zhang, Wei Liu, Wei Yao, Le Kang & Enjun Gao

  2. Nikolaev Institute of Inorganic Chemistry, Lavrentiev Avenue 3, Novosibirsk, Russian Federation, 630090

    Vladimir P. Fedin

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  1. Yan Zhang
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YZ: conceived and completed the experimental work. WL: validation and investigation. WY: review and editing. LK: Data supplementation. EG: conceptualization, funding acquisition, supervision. VPF: visualization.

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Correspondence to Wei Yao or Enjun Gao.

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Zhang, Y., Liu, W., Yao, W. et al. An electrochemical sensor based on carbon composites derived from bisbenzimidazole biphenyl coordination polymers for dihydroxybenzene isomers detection. Microchim Acta 191, 20 (2024). https://doi.org/10.1007/s00604-023-06099-x

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