Carbon-based Thin-film Electrodes And Arrays:Fabrication And Electrochemical Sensing Applications

Carbon nanomaterials,such as carbon nanotubes and graphene,are the advanced materials in the preparation of flexible transparent conductive film,owing to their unique structure,excellent optical property,high conductivity,chemical and mechanical stability.Furthermore,in the field of electrochemical sensor research,they are widely used as modified material,and also the ideal conductive material for the construction of substrate electrode.With the rapid development of the environmental monitoring,food safety and medical diagnosis et al.,the demand of the applied electrochemical sensor with the advantages of low cost and quick response is increasing.While the simple and controllable electrode preparation technology is of great significance for the practical application of sensors.In view of the existing problems of the renewable of contaminated electrode,as well the complex and high cost preparation technology of electrode array in the process of constructing electrochemical sensors,this thesis concentrated on developing a simple and controllable preparation method for carbon-based thin-film electrodes and arrays,studying and exploring the potential applications of the fabricated carbon-based electrochemical sensors.The research contents include:(1)Multi-walled carbon nanotubes(MWNTs)conductive film was obtained by vacuum filtration of the homogeneous carbon nanotubes aqueous solution with the assistant dispersion of anionic surfactant SDS,and then sealing and transfering the MWNTs film by polydimethylsiloxane(PDMS)to achieve flexible PDMS-MWNTs composite film electrode.The exposed cutting section was used as the electrochemical sensing interface and applied to the detection of environmental estrogen bisphenol A.The results of the electrochemical analysis demostrate that the regeneration and repeated usage of the fabricated single electrode can be easily realized by simply cutting the contaminated electrode.With the synergistic sensitization effect of CTAB,the reusable and sectile PDMS-MWNTs composite based electrochemical sensor realized the rapid and sensitive detection of bisphenol A.Besides,bisphenol A in practical sample,such as thermal printing paper,was detected by this sensor,and acceptable recoveries was obtained.(2)Hydrophobic paper tape based patterned electrode array template was successfully obtained through the laser engraving technology.The graphene and single-walled carbon nanotubes conductive ink were respectively prepared by 1-Methyl-2-pyrrolidone(NMP)ultrasonic exfoliation of graphite and anionic surfactant ultrasonic dispersing single-walled carbon nanotubes.The carbon-based electrode arrays were fabricated by vacuum filtration with patterned array template on PVDF filter membrane,thus,the integrated and low cost carbon-based three-electrode arrays were successfully prepared with simple device.The filtration carbon film three-electrode system have good electrochemical response towards potassium ferricyanide,bisphenol A,dopamine,and glucose,indicating the good electrochemical performance of integrated graphene and carbon nanotube three-electrode.Thus,a simple and low cost carbon-based electrode array preparation method was established,and the integrated carbon-based electrochemical sensors have potential application value.