| Electrochemical sensors have always attracted the researcher’s attention because of the advantages,such as fast response,high sensitivity,good stability,quantitative analysis,easy to miniaturization and low cost.In the chemical,biotechnology,medicine,environmental protection and other fields have used widely.Nanomaterials attract considerable attention for its different shape,composition,size,quantum size effect,surface area and small size effect.And it possesses many excellent properties,such as the specific surface area,strong adsorption ability,high catalytic,and the high surface reactivity.Compared with other carbon materials（e.g.carbon nanotubes,graphene,glassy carbon）,carbon black（CB）nanoparticles can be better applied in the field of electrochemical detection because of the advantages of cheap price,good conductivity,large specific surface area and strong adsorption performance.In nanomaterials,metal nanoparticles have attracted more interest of researchers because of their important properties and multiple applications.Metal nanoparticles have large surface area and high free energy,which can significantly increase the electrode sensitivity when modifying the electrode.The introduction of metal nanoparticles into modified electrodes for catalysis and rapid detection of certain substances have a good application prospect.Two-dimensional（2D）nanomaterials,including graphitic carbon nitride（g-C3N4）,zinc oxide（ZnO）and so on,have important applications in the fabrication of high-performance electrochemical sensors due to the excellent electronic and physical properties generated by their two-dimensional structures.The work of this paper focuses on the application of the carbon black nanoparticles and its composite materials in the electrochemical sensor research.The main content is divided into the following three parts:Ⅰ.The preparation of glassy carbon electrode modified with graphitic C3N4/carbon black/gold nanoparticles and its electrocatalytic performance for hydrazine sulfate.In this study,a novel method for electrochemical detection of hydrazine sulfate was established with graphitic C3N4/carbon black/gold nanocomposites as modified material.The cyclic voltammetry,impedance method and other electrochemical characterizations and measurements were used.The experimental results show that the modified electrode g-C3N4/CB/AuNPs/GCE can detect hydrazine sulfate in the range from 2.5×10-5 to 1.5×10-3 mol·L-1,with detection limit of 1.6×10-6 mol·L-1（S/N=3）.This experiment shows that g-C3N4NPs、CBNPs and AuNPs have obvious catalytic properties for hydrazine sulfate,which can be detected in real water samples.Ⅱ.Glassy carbon electrode was modified with zinc oxide nanoparticles/carbon black nanocomposites and electrochemical detection of nitrite.In this study,zinc oxide/carbon black（ZnO/CBNPs）composite nanomaterials were synthesized and modified on the electrode surface.The electrochemical behavior of modified electrode were studied by the methods of cyclic voltammetry,AC impedance and differential pulse voltammetry.The results show that the modified electrode has a good catalytic effect on nitrite.Under optimization conditions,the linear range of nitrite detection is from 5×10-7 to 4×10-3 mol·L-1,and the detection limit is 8.2×10-8 mol·L-1（S/N=3）.In addition,there is no obvious interference of glucose,ascorbic acid,uric acid,hydrazine sulfate and other substances in the detection of nitrite.The results are satisfactory for the detection of nitrite in real samples.Ⅲ.The preparation of graphitic C3N4 nanoparticles/zinc oxide/carbon black nanocomposites modified electrode and determination of hydroquinoneIn this work,graphitic C3N4 nanoparticles/zinc oxide/carbon black nanocomposites were used as modification materials to construct a novel modification method for electrochemical detection of hydroquinone.The electrochemical behavior of this electrode were studied by cyclic voltammetry,AC impedance and differential pulse voltammetry.The experimental results show that the modified electrode g-C3N4/ZnO/CBNPs/GCE can significantly enhance the redox peak current of hydroquinone.This method is fast,simple and sensitive.The linear range of hydroquinone detected by g-C3N4/ZnO/CBNPs/GCE electrode is from 8×10-7 to4×10-4 mol·L-1 and the detection limit is 2.6×10-8 mol·L-1（S/N=3）.The electrochemical sensor has a good effect on the detection of hydroquinone in real water and has a good application prospect. |
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