Preliminary Study On Dielectric Constant And Thermal Properties Of Graphene

Since graphene was first prepared in 2004,because its unique carbon structure had attracted the attention of many researchers.After many years of research,it had been found that graphene had excellent thermal,electrical,mechanical,optical and other properties,which made it widely used in materials,energy and other fields.Therefore it was of great significance to study the dielectric constant and thermal properties of graphene.In this paper,the dielectric constant of graphene solution and the thermal properties of graphene materials were studied.In the study of the dielectric constant of graphene solution,the microwave resonant cavity perturbation method was mainly used in the experimental measurement,and the value of dielectric constant was calculated according to the experimental results.By changing the concentration of graphene solution(5 g/ml?2.5g/ml and 1.25 g/ml),the diameter of capillary(0.5mm and 0.9 mm)containing the graphene solution,and the depth of entering the resonator(1mm-6mm,every 1 mm),the real and imaginary parts of the dielectric constant of graphene could be obtained under different conditions,as well as influence of the capillary on the measurement results.HFSS simulation software was used to simulate the resonator before and after the load was added,and the obtained data were compared with the experimental data.It was found that the maximum relative error between the loaded resonant frequency of the resonator under the software simulation and the experimental measurement was 1.29%.For the study of the thermal characteristics of graphene materials,in the theoretical aspect,the ANSYS Workbench software was used to analyze the thermal characteristics of two glass lenses and the two glass lenses after adding graphene in the middle,and the shape variables of the materials with the increase of temperature were obtained.In the aspect of experimental,two glass lenses and two glass lenses with graphene materials(copper-based graphene,silica-graphene and graphene dried)were measured by the improved speckle measurement device,and the speckle interference images of the object to be measured at different temperatures were obtained.Then Matlab software was used to process the images,and the change of interference fringes before and after the temperature change was obtained.It could be seen from the comparison that the thermal conductivity of graphene dried increased gradually from 53?.