| Phenolic compounds are usually formed through the hydrogen atoms on the benzene ring replaced by hydroxyl groups,widely using in metallurgy,mechanical manufacturing,petrochemical industry,chemical organic synthesis industry,plastics,medicine,pesticides and other fields.Because phenolic compounds are widely used and have certain chemical toxicity,they are harmful to environmental safety and human health.Therefore,phenolic organic pollutants are listed as priority pollutants in many countries and regions,and it is particularly necessary to develop an efficient,rapid,convenient and practical monitoring method.As the current star of the family of the conductive polymer molecules,owing to its high conductivity,good environmental stability,biological compatibility and other advantages,poly（3,4-ethylenedioxythiophene）（PEDOT）has been widely used in many fields including thermoelectric materials,energy,batteries and electrochemical sensor.In this thesis,electrochemical sensors based on PEDOT have been successfully applied to the detection and analysis of three kinds of phenols.（1）In this work,electrode based on poly（3,4-ethylenedioxythiophene）（PEDOT）was employed for the fabrication of an efficient sensor for 4-chloro-3-methylphenol（PCMC）detection.To improve the dispersity and increase the specific surface area of PEDOT,core-shell structured Ui O-66-NH2@PEDOT was designed by in-situ oxidation method using Zr-based metal-organic framework（Ui O-66-NH2）as template.In addition,to achieve a further increased active surface area and electron transfer rate of the modified materials,graphene aerogel（GA）was utilized as substrate material for the assembly of Ui O-66-NH2@PEDOT.Then,the obtained Ui O-66-NH2@PEDOT/GA modified electrode was employed as an electrochemical sensor for PCMC detection.Under the optimized experiment condition,the Ui O-66-NH2@PEDOT/GA electrode showed a good linear range of0.6-18μM,as well as a low detection limit of 0.2μM.The Ui O-66-NH2@PEDOT/GA electrode was applied toward the detection of PCMC in tap water with good recovery.（2）Poly（3,4-ethylenedioxythiophene）:poly（styrenesulfonate）（PEDOT:PSS）is a readily available copolymer that comes as an aqueous dispersion with good processability.A flexible voltammetric sensor for the widely used food stabilizer tert.butylhydroquinone（TBHQ）was constructed by using a film of PEDOT:PSS.The electron transfer efficiency of the electrode was enhanced by dopingwith dimethyl sulfoxide（DMSO）,and mass transport at the electrode-electrolyte interface was increased by adding the cationic surfactant cetyltrimethylammonium bromide（CTAB）which acts as a sorbent for TBHQ.SEM,AFM,XPS,UV-vis and electrochemical analysis were conducted to characterize the properties of the electrode.After optimization of the experimental conditions,the electrode operated at a working potential of 0.17 V（vs.SCE）has a linear response in the 0.5-200μM TBHQ concentration range and a lower detection limit of 0.15μM（at S/N=3）.It was applied for the determination of TBHQ in spiked real samples.（3）In this work,poly（3,4ethylenedioxythiophene）:poly（styrene-sulfonate）（PEDOT:PSS）based aerogel was prepared through freeze drying the as-prepared PEDOT:PSS hydrogel precursor.With injecting multi-wall nanotubes（MWCNTs）suspension into PEDOT:PSS hydrogel precursor,the obtained PEDOT/PSS/MWCNTs aerogel showed satisfactory electrochemical performance and was successfully applied for the sensitive detection of 2,4-dichlorophenol（2,4-DCP）.SEM and Raman spectra were conducted to characterize PEDOT/PSS/MWCNTs aerogel,which showed several desirable features of modified sensor materials.After optimizing the experiment condition,the fabricated PEDOT:PSS/MWCNTs aerogel/GCE showed a low detection limit of 1n M（S/N=3）and a wide linear range of 0.008-15μM.The fabricated electrodes were successfully applied for the determination of 2,4-DCP in real samples with satisfying recovery. |
