Preparation,Characterization And Application Of Modified Electrodes With Electroactivity And Thermosensitivity

Temperature-responsive high molecular polymers have received more and more attention due to their novel properties and functions.The gel material prepared by the mechanism of the initiator initiating the cross-linking agent greatly increases its stability due to the cross-linking of its component structures.On the basis of not destroying the inherent properties of its monomers,the gel material is improved the unstable characteristics of traditional polymers.Polymeric ionic liquids can achieve adjustable anions and cations due to their ion exchange properties,making them an excellent medium in synthetic chemistry.Therefore,a gel that integrates PNIPAm and ionic liquid is prepared,which not only retains the temperature responsiveness of PNIPAm and the ion exchange property of ionic liquid,but also improves the instability of traditional materials in application.In addition,the ion exchange of the ionic liquid can be used to support functional anions and cations to realize the preparation of functional gels.Based on the above research,this thesis mainly carried out the following work:1.First use RAFT polymerization,under the action of the initiator to initiate the crosslinking agent,the ionic liquid monomer and the NIPAm monomer are copolymerized to prepare a PNIPAm-based gel poly（NIPAm-co-Vi Et Im Br）gel,and then use the ionic liquid fragment The ion exchange property of Au NPs is supported by the electrostatic attraction of Au Cl₄^-,the precursor of Au NPs,and then reduced in situ to prepare a temperature-sensitive responsive composite gel containing metal particles poly（NIPAm-co-Vi Et Im Br）/Au gel.Then by using XPS,TEM,Zeta potential and FT-IR methods to characterize the morphology,structure,and properties of the gel,the experimental results show that we have successfully synthesized the gel with temperature-sensitive responsiveness and ion exchange the gel poly（NIPAm-co-Vi Et Im Br）/Au gel.2.Prepare temperature-responsive electroactive gel materials poly（NIPAm-co-Vi Et Im[Fc COO]）gel and poly（NIPAm-co-Vi Et Im[Fc COO]）/Au gel using electrostatic attraction,and their structure,the composition was studied.They were prepared into electrochemically active modified electrodes poly（NIPAm-co-Vi Et Im[Fc COO]）gel/GCEand poly（NIPAm-co-Vi Et Im[Fc COO]）/Au gel/GCE,and these two types of electrodes were investigated respectively.Active modification of the electrochemical performance of the electrode.Experimental results show that these two modified electrodes have temperature responsiveness,good stability,and reversible cycles.Moreover,the electrochemical signal of poly（NIPAm-co-Vi Et Im[Fc COO]）/Au gel/GCE modified electrode is stronger than that of poly（NIPAm-co-Vi Et Im[Fc COO]）gel/GCE modified electrode.Next,the electro-active modified electrode poly（NIPAm-co-Vi Et Im[Fc COO]）/Au gel/GCE was further investigated for the electrocatalytic performance and detection performance of ascorbic acid under different temperature conditions.The results show that the electrocatalytic performance of poly（NIPAm-co-Vi Et Im[Fc COO]）/Au gel/GCE modified electrode is temperature-responsive,and its ascorbic acid can achieve good electrocatalytic performance at 20℃or 50℃.Under these conditions,the electrode material is hydrophobic,leading to electrocatalytic sealing,showing a"closed"state.Under the condition of 20℃,the current signal of poly（NIPAm-co-Vi Et Im[Fc COO]）/Au gel/GCE modified electrode has a good linear relationship with the concentration of ascorbic acid,and its detection range is:0.100m M～25.8 m M,The sensitivity is 1.87μA·cm^-2·m M^-1,and the detection limit is0.0929 m M.And its catalysis of ascorbic acid shows good anti-interference performance.