Glucose,Dihydroxybenzene Sensor And Electrocatalytic Performance Research Based On Graphene/Polyimide Functional Materials

Graphene/polyimide function material with excellent electrical conductivity and mechanical,exhibits good flexibility,high and low temperature resistance,corrosion resistance.As a new type of conductive polymer electrode,it broadens the scope of modified electrodes,and has important scientific significance and practical value for electrochemical research.In this master thesis,graphene/polyimide?PI/RGO?functions as the electrode material,the modified electrodes were prepared by using cyclic voltammetry?CV?and other technologies;The structure,morphology and composition of the modified electrode were analysed by characterization methods,such as X-ray diffraction?XRD?,X-ray photoelectric spectroscopy?XPS?,scanning electron microscope?SEM?,transmission electron microscopy?TEM?.The main contents include: 1.Hexagram-like CoS-MoS₂ composites with enhanced activity for hydrogen evolution reactionHexagram-like CoS-MoS₂ composites were prepared on Indium tin oxide?ITO?conductive glasses via cyclic voltammetry electrodeposition using Co?NO₃?₂ and?NH₄?₂MoS₂ as precursors and tested for application in hydrogen evolution reaction?HER?.The structure of CoS-MoS₂ composites was characterized by X-ray diffraction?XRD?,scanning electron microscope?SEM?and X-ray photoelectron spectrum?XPS?.Electrochemical characterizations indicate that CoS-MoS₂ composites exhibit more excellent catalytic activity and stability than MoS₂.Compared with pure MoS₂,the hexagram-like CoS-MoS₂ composites with increased specific surface area improved the density of exposed active sites,and the Co binding S edges in CoS-MoS₂ composites promote the number of highly catalytic edge sites and decreased the binding energy ?GH.Moreover,the effects of different substrates on the CoS-MoS₂ composites were also investigated.Our further understanding of this highly active hydrogen evolution catalyst can facilitate the development of economical electrochemical hydrogen production systems.2.Amperometric glucose biosensor based on AuPd modified reduced graphene oxide/polyimide film with glucose oxidaseAuPd bimetallic compositehas been prepared on reduced graphene oxide/polyimide?PI/RGO?film by electrodeposition.The AuPd fabricated on PI/RGO film,which exhibits good conductivity and excellent catalytic properties.AuPd/PI/RGO electrode shows high activity towards hydrogen peroxide?H2O2?for coupling effect between AuPd and PI/RGO film.Based on high electrochemical activity toward H2O2,an amperometric glucose biosensor has been also described,which was achieved by the immobilization of glucose oxidase?GOx?onto the AuPd/PI/RGO electrode.The proposed biosensor displayed good amperometric response characteristics towards glucose,such as a fast response within 3 s and a wide linear range from 0.024 mM to 4.6 mM.In addition,the biosensor was utilized for the detection of glucose in human blood serum that displayed satisfactory results.The present finding might open up a new avenue in the development of high performance bimetallic materials on appropriate supporting materials for electrochemical sensing.3.Electroless deposition of Au nanoparticles on reduced graphene oxide / polyimide film for electrochemical detection ofhydroquinone andcatecholAnelectrochemical sensor for determination of hydroquinone?HQ?andcatechol?CC?was developed using Au nanoparticles?AuNPs?fabricated on graphene oxide / polyimide film?PI/RGO?by electroless deposition.Theelectrochemical behaviours of HQ and CC at PI/RGO-AuNPs electrode were investigated bycyclic voltammetry?CV?and differential pulse voltammetry?DPV?.Under the optimized condition,the current responses at PI/RGO-AuNPs electrode were linear over ranges from 1?M to 654 ?M for HQ and from 2 ?M to 1289?M for CC,with the detection limits of 0.09 ?M and 0.2 ?M,respectively.The proposed electrode exhibited good reproducibility,stability and selectivity.In addition,the proposed electrode was successfully applied on the determination of CC and HQ in tap water and the Yellow River samples.