Preparation And Electrochemistry Performance Of Nanoparticles Based On Non-covalent Functionalized Graphene

Graphene,as a two-dimensional plane with unique properties of quasi crystal materials,loaded with high catalytic activity of gold nanoparticles(AuNPs),can be used as electrode materials,which not only accelerates the electron transfer rate,but also increases the effective area of the working electrode,improves the activity of the center electrode,thus building an efficient platform for electrochemical sensors.Meanwhile,the graphene hollow spheres prepared by mesoporous silica nanoparticles,the ideal template of synthetic graphene hollow sphere,own a promising application prospect.in being.used as electrode materials in the electrocatalytic oxygen reduction reaction.In this paper,we constructed two different methods of composite graphene nanoparticles,by making simple,low cost and highly productive noncovalent methods.The morphology,structure and electrochemical applications of two kinds of graphene were characterized,analyzed and studied,details are as follow:1.Functionalized graphene was synthesized via thiol-click reactions,and then the negatively charged AuNPs load to GR-Cys through electrostatic interaction orientation under acidic conditions.,so,the GR-Cys-AuNPs composite materials were successfully synthesized.Characterization of GR-Cys and GR-Cys-AuNPs composites by TG,IR,TEM,Raman spectra,XRD and XPS showed that graphene was successfully covalently functionalized and AuNPs distributed uniformly and efficiently.The obtained functionalized graphene/AuNPs composites exhibited excellent electrochemical properties investigated by cyclic voltammetry(CV)and differential pulse voltammetry(DPV).The composites electrode exhibited high stability and good selectivity for UA and FA,and showed a good linear relationship in the concentration range of 0.1～300 mol·L-1 and 0.5～150-mol·L-1,Moreever,the detection limit of 0.08μM and 0.035 μM(S/N = 3),respectively.2.A new hollow sphere hollow(Graphene)has been designed and synthesized.The successful construction of the Graphene space sphere is to use a non-covalent π-πbond to form a new graphene-coated mesoporous silica ball structure,and then the inner SiO2 is etched by carbonization to obtain the internal hollow graphene sphere The morphology and structural characteristics of graphene hollow spheres were characterized by SEM,TEM,XRD,Raman and XPS,the integrity and low defects of the hollow spheres were determined.Then,the glassy carbon electrode modified by graphene hollow sphere was used to study the electrocatalytic performance of graphene hollow sphere.The CV and electrochemical impedance spectroscopy(EIS)show that the hollow spherical structure has better electrocatalytic activity than the graphene lamellar structure,and has potential application value.