Study On Irradiation Repairation Of Pre-cracked Graphene And The Intermolecular Forces Of The Bilayer Graphene

Graphene is now recognized as a new strategic materials in the 21 th century.More than a decade,graphene has been a hotspot in the research of the scientists since it was successfully prepared in laboratory in 2004 for the first time,which can exist alone.Perfect graphene has ideal two-dimensional structure and very excellent properties,such as mechanical,electrical,optical,thermal properties and so on.Due to the restrictions in the graphene manufacturing,the presence of defects in graphene structures is almost inevitable and the defects can affect its excellent mechanical properties.With further resarch,the intermolecular force between the double-layer graphene also cause the attention of scientists and the research is under way.This study not only provides a new theoretical basics to know the intermolecular force of two-dimensional materials,but also provides a way to know the graphene better,which has important significance to the graphene's development,innovation and practical application.In conclusion,it is necessary to heal the crack of graphene and the intermolecular force between the bilayer graphene.In this paper,the main research content is as follows:Firstly,we study the repariation of cracked graphene by C ions irradiation.The molecular dynamics simulations are carried out to study the performance of graphene with a pre-crack which is irradiated by C ions.First,the repairation mechanism of defect graphene is investigated.The tensile properties of pristine graphene and graphene with a crack are simulated and compared for the cases of irradiation and without irradiation.The simulation results demonstrate that the irradiation can be used to repair the crack in graphene and can improve its mechanical properties.It means that the repairation of defected graphene by irradiation is feasible.The influences of theirradiation dose and irradiation energy on the irradiation effects are analyzed.We found that both irradiation dose and irradiation energy have important influence on the defects repairation.Furthermore,the temperature effect on tensile properties of graphene after repairation are also studied for temperature range of 0.1K to 1500 K.it shows that the temperature has a great effect on the mechanical properties of the irradiated graphene.With the increase of temperature,the tensile strength and failure stain of defected graphene decrease linearly.Secondly,we study the intermolecular force of bilayer graphene after C ion irradiation.First the rules of the bonding between the bilayer graphene sheets are revealed.The irradiation results and the intermolecular force(and as well as called interlaminar strength)of bilayer graphene in different irradiation conditions are analyzed.The simulation results show that the irradiation can be used to enhance the interlaminar strength of bilayer graphene,but only under the reasonable irradiation condiation.In the process of irradiation simulation,there are two distinctive kind of bonds formed between the graphene sheets.During tensile,the irradiated graphene's stripping tensile curve quickly reaches the maximum,then show a trend of fluctuations and falling.This study shows that the number of new bonds and their distribution influence the rule of stripping tensile curve.