Equipment Structure And Experimental Study Of Preparation Of Graphene By Mechanical Method

According to the traditional theory,it is difficult for two-dimensional crystals to exist independently because of thermal instability.However,since the discovery of graphene in 2004,it had broken the restriction of traditional theoretical research and opened the research field of new two-dimensional nano-functional materials,which is of great significance.In recent years,the study of graphene has not decreased,and graphene has shown excellent properties in electrical,thermal and mechanical properties.These excellent properties are expected to be applied in energy storage,composite materials,high-performance nano-electronic devices,field emission materials and other fields,and have a very wide application prospect.Graphene has been described by the scientific community as possible to replace silicon as a future semiconductor material.The great application prospect of graphene has led to the study of its preparation method.In recent years,the preparation methods of graphene have been mostly concentrated in the chemical direction.However,many discoveries of graphene's physical properties is derived from graphene prepared by mechanical stripping.In this paper,in view of the mechanical ball grinding process,according to the current research,graphene is more mature in vertical mixing grinding method and the planet type ball mill method.In order to solve the inevitable exists of the phenomenon of grinding ball impacting abrasive materials in the above two ball grinding method,we put forward a new type ball mill that is a kind of preparation of graphene which can provide pure shear stripping.The unique two-dimensional crystal structure of graphene requires that,in the process of preparing the mechanical stripping,how to preserve this two-dimensional lattice structure as well as to obtain large diameter-thick ratio of graphene layersbecome the key issue.In the theoretical study of the crush grinding,grinding ball impacting target material is favorable for refined grinding objects,but not good at preserving the crystal structure of the two-dimensional graphene and obtaining larger neck arm of graphene layers.Therefore,it is of great significance to propose a ball grinding method which can provide effective shear effect and can avoid grinding ball impact.In this paper,the new type ball mill equipment is the research object.The domestic and foreign theoretical researches for mechanical stripping process of the preparation of graphene as the foundation,based on EDEM discrete element simulation software which analysis the motion law of grinding balls in the new ball mill equipment,we study the feasibility of the ball mill method preparation of graphene.With SDS as dispersant,we determine the certain process parameters such as drum rotational speed,the diameter of grinding ball to prepare graphene in the experimental way.By characterizing the quality of graphene sheet by SEM and Raman spectroscopy,we demonstrate the feasibility of this method.Through research and analysis,the new type ball mill equipment can prepare a few layers and large diameter-thick ratio graphene.At the same time,contrasting the SEM figure of the sample of different milling time shows that the equipment is effective to avoid the grinding balls from the impact of damage behavior on flake graphite layer.