| Due to its unique two-dimensional nanostructures and excellent physical and chemical properties,graphene has been widely concerned by the scientific community.In the field of electrochemical sensing,graphene has been of great value both in theory and in experimental research.MOFs material,rised from early 21 st century,has also fully demonstrated its scientific research in various fields significance and application prospects in recent years.The application of graphene materials in the field of electrochemical sensing has become more mature,especially in the functionalization of graphene,however,by controlling its pore structure to improve its application in the modified electrode less.In this paper,from the control of graphene pore structure,combined with MOFs porous and high porosity characteristics of the design of different sensing interface to build the sensor,achieve environmental hormones and hydrazine high sensitivity detection and analysis.The main points of this thesis are summarized as follows:(1)(SiC-EG)was prepared by chemical vapor deposition(CVD).The composites of SiC wire were prepared at different temperatures(1200 ?,1300 ? and 1400 ?,respectively)material.The electrochemical properties of SiC-EG were measured by cyclic voltammetry(CV)and electrochemical impedance spectroscopy(EIS).The electrochemical properties of SiC-EG prepared at 1300 ? were investigated.The effect of SiC-EG modified electrode on the detection of octylphenol(OP)was studied.The linear correlation coefficient of OP in the range of 0.1-10 ?mol / L was obtained under the optimal conditions.The linear correlation coefficient r = 0.998,The detection limit was 35 nmol / L.(2)Metal-organic framework/reduced graphene oxide(MIL-101(Cr)@rGO)materials were prepared through a simple chemical reduction method.The morphology,structure and properties of the obtained composite were characterized by scanning electron microscopy,transmission electron microscopy,Raman,Brunner-Emmet-Teller and electrochemical techniques.The successful reduced graphene oxide coating in the MIL-101(Cr)@rGO improve the electronic conductivity of MIL-101(Cr)effectively.MIL-101(Cr)@rGO composite have been applied to construct the MIL-101(Cr)@rGO coated electrode and further used for the determination of 4-nonylphenol(4-NP).The results demonstrated that the electrochemical signals and peak profiles of 4-NP was significantly improved by the modified material,benefit from the synergistic effect from high conductivity of rGO and large specific surface area of MIL-101(Cr).By applying differential pulse voltammetry,the monitoring of 4-NP in the range of 0.1 ?mol/L to 10 ?mol/L was realized(r=0.999).The detection limit was 10 nM.This novel electrochemical sensor is thus promising for the environmental monitoring of 4-NP in future.(3)The MIL-101(Fe)was prepared by hydrothermal method,and the morphology of MIL-101(Fe)was characterized by transmission electron microscopy(TEM).MIL-101(Fe)was applied to the surface of the glassy carbon electrode.Then,a layer of gold nanoparticles was deposited on the surface of the electrode by cyclic voltammetry to obtain gold nanoparticle/metal organic framework modified glassy carbon electrode.The prepared electrode was subjected to transmission electron microscopy and electrochemical characterization.The results show that the gold nanoparticles are successfully modified on the surface of MIL-101(Fe),The prepared sensor has a significant electrocatalytic effect on hydrazine,benifit from the high porosity of MIL-101(Fe)and the high catalytic performance of gold nanoparticles.And the oxidation mechanism of hydrazine on the surface of modified electrode was studied.The preparation conditions and the detection conditions of the electrode were optimized by examining the oxidation factors of hydrazine on the electrode.Under the optimal experimental conditions,the detection limit of hydrazine was 3 nmol in the range of 0.01 ?mol/L to 40.0 ?mol/L,which provided a new method for the quantitative detection of hydrazine. |
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