The Design And Application Of Electrode Sensor Based On Carbon Dots/Multi-walled Carbon Nanotubes In Detection Dihydroxybenzene Isomers

Benzodiazepines are widely used in leather making,pesticide,spice,cosmetics,drugs,antioxidants,and dyes.Therefore,catechol and hydroquinone is important pollutants in water,even a small amount of water in the biology has serious harmful effects.The detection of catechol and hydroquinone main methods,such as chromatography,spectrophotometry,chemiluminescence method and electrochemical method,electrochemical method with its simple,easy operation,high sensitivity and other advantages gained increasing attention.And carbon materials for their special excellent structural characteristics,are widely used in electrochemical analysis.This article mainly through microwave synthesis,carbon dots,multi-walled carbon nanotubes as well as the synthesis of metal oxide composite material,and its modified electrodes after the detection of hydroquinone and catechol electrochemical performance.The main research content is as follows:?1?carbon dots/multi-walled carbon nanotubes/carbon dots composite modified glassy carbon electrode?CDs/MWCNTs/CDs/GCE?preparation:By transmission electron microscopy,scanning electron microscopy?SEM?,atomic force microscopy,Fourier infrared spectroscopy on CDs/MWCNTs/CDs/GCE composite were characterized,and by using cyclic voltammetry?CV?and differential pulse voltammetry?DPV?testing its electrochemical performance.Applying modified electrode to hydroquinone,catechol and benzodiazepines detection,the sensor has the advantages of high sensitivity,specificity and good stability.The experimental results show that the CDs/MWCNTs/CDs/GCE compound has excellent selective electrode hydroquinone isomers,the detection limit of HQ,CC and RS was reached 0.07?M,0.06?M,0.15?M,respectively.The modified electrode was used for the actual water samples and obtained accurate results.?2?zinc oxide–carbon dots/multi-walled carbon nanotube composite modified glassy carbon electrode?ZnO-CDs/MWCNTs/GCE?preparation.Zinc oxide has good electrical conductivity,and multi-walled carbon nanotubes have specific conductivity and large specific surface area,which is both are used in the electrochemical analysis.By Fourier infrared spectrum?FT-IR?and transmission electron microscopy?S EM?show that the carbon dots surface of carboxyl,can connect zinc oxide on the hydroxyl and carboxyl tubes,make the combination of effective together.Compared to the bare GCE,CDs/GCE,ZnO/GCE,MWCNTs/GCE,ZnO-CDs/GCE electrode,ZnO-CDs/MWCNTs/GCE in detection of catechol and hydroquinone has good detection ability.Under the best conditions,the detection limit of hydroquinone and catechol was 0.04?M,0.02?M,respectively.?3?the manganese oxide–carbon dots/multi-walled carbon nanotube composites modified glassy carbon electrode?MnO₂-CDs/MWCNTs/GCE?preparation.The single mode microwave synthesis was used to prepare the flower manganese oxide which can greatly expand the specific surface area of the composite material.The manganese oxide–carbon dots/multi-walled carbon nanotube composites modified electrodes was used for quantitative detection of hydroquinone and catechol in real water sample.The oxidation potential difference??Ep?of hydroquinone and catechol was 110 mV and the detection limit of hydroquinone and catechol was 0.06?M,0.04?M,respectively,which showed that MnO₂–CDs/MWCNTs/GCE displayed as high sensitive selection test.