A novel electrochemical sensor based on mesoporous carbon hollow spheres/ZIF-67-derived Co-embedded N-doped carbon nanotubes composite for simultaneous determination of dihydroxybenzene isomers in environmental water samples

Dihydroxybenzene isomers were environmental pollutants which were potential threat to human health. Accurately and rapidly detection of them is very valuable. In this study, a dihydroxybenzene isomer sensor based on mesoporous carbon hollow spheres/zeolitic imidazolate frameworks (ZIF)-derived Co-embedded N-doped CNTs (MCHSs/Co@N-CNTs) was proposed. The MCHSs/Co@N-CNTs, with excellent conductivity and electro-catalytic, presented excellent electrochemical simultaneous detection for phenolic compounds. Under optimal conditions, the MCHSs/Co@N-CNTs/GCE showed wide linear range (CC: 2.5 mu M-100 mu M, HQ: 1.0 mu M-150 mu M, RS: 20 mu M-1000 mu M) and the detection limit (LOD) of CC, HQ and RS were 0.46, 0.27 and 4.21 mu M (S/N = 3), respectively. Additionally, the reaction sites and mechanism of phenolic compounds were revealed by analyzing the electrochemical behavior with the help of density functional calculation. Moreover, the sensor showed satisfactory results in the determination of phenolic compounds in environmental water samples.

Automated summary

This study proposes a sensor for dihydroxybenzene isomers based on mesoporous carbon hollow spheres/zeolitic imidazolate frameworks-derived Co-embedded N-doped carbon nanotubes (MCHSs/Co@N-CNTs). The sensor exhibits excellent conductivity and electro-catalytic properties, enabling simultaneous electrochemical detection of phenolic compounds. Under optimized conditions, the sensor shows a wide linear range and low detection limits. Density functional calculations help reveal the reaction sites and mechanism of phenolic compounds. The sensor also demonstrates satisfactory results in detecting phenolic compounds in environmental water samples.