Fabrication And Versatility Of Thin Film Made By Multiform Graphene

In the face of the rapid development of electronic integrated technologies,it is of utmost importance to prepare a kind of thin-film material that is lightweight,flexible,and versatile in the field of heat dissipation and electromagnetic interference shielding.Graphene is recognized as a new material with high electrical conductivity,high thermal conductivity,and excellent mechanical properties at present.Two-dimensional graphene thin film which has many advantages such as light weight,high performance,and flexibility meets the needs of the development of electronic integration requiring small size as well as multifunction integrated electromagnetic interference shielding and heat dissipation.At present,the research on graphene thin films is limited to the single properties of graphene thin films,and the versatility cannot be taken into consideration.To solve the above problems and improve kinds of properties of graphene two-dimensional macroscopic body further,this study proposed that adding graphene with different forms could improve properties of graphene oxide system,taken advantage of the advantages of graphene oxide and graphene fillers and studyed the effects of varity graphene fillers on the performance of graphene films.The main contents of this paper are as follows:After chemically-cutting,graphene nanoribbons were evenly mixed with the well-dispersed graphene oxide,a mixed sponge was made by freeze-drying,and the sponge was prepared into a hybrid film under a high-temperature vacuum hot pressing condition.The conjugate actionbetween the layers was formed through the introduction of graphene nanoribbons,which improved the mechanical properties of the film.The fracture strength of the prepared hybrid film is 75 MPa,which improves the mechanical properties of the film by nearly 25%.The film also has thermal conductivity as high as 510 W·m-1·K-1 and the electromagnetic shielding effectiveness reaches 63 d B.In order to reduce the defect of the system,the graphene with low defect and good crystallinity was introduced into the graphene oxide.After mixing graphene and graphene uniformity,the film was prepared using the Meyer method,and the prepared film was respectively subjected to 1500°C and 2000°C high temperature processing.The introduction of graphene effectively reduces the defect content of the system,and improves the thermal and electrical conductivity of the material.After processing at 1500°C,the thermal conductivity of the hybrid film can reach 900 W·m-1·K-1.The electromagnetic shielding effectiveness can reach 77 d B.At the same time,the addition of graphene introduces conjugate.When the content of graphene is 25%,the breaking strength can reach 105 MPa.After treating at 2000°C,the graphene oxide sheets were repaired totaly,and large-scale repaired graphene oxides played a major role in the thermal conductivity.The highest thermal conductivity is obtained when the graphene oxide content was 75%.It is 1800 W·m-1·K-1,which is higher than that prepared by the graphene oxide film at the same temperature nowdays,increasing by nearly 50%.Conjugation is still present at a high temperature of 2000°C,and the tensile strength increases with increasing graphene oxide content.When the graphene content is 25%,the tensile strength is 65 MPa,nearly 60% increasing compared to pure graphene oxide.The fracture elongation is as high as 7%.,while having 80 d B of electromagnetic shielding effectiveness.