Irradiation Property Of WS₂ Nanosheets And Graphene

With the continuous development of nano science, the application of nano materials is more and more widely. For example, WS2 nanosheets have excellent lubricating properties and chemical stability. They are suitable for lubrication which worked in space environment or catalyst materials in industry. Graphene also has been widely applied in aerospace and nuclear field because of its excellent physical and chemical properties. So the studying the irradiation changes of WS2 nanosheets and graphene are particularly urgency.The WS2 nanosheets are irradiated by different electron energies, it is found that the damage to the WS2 nanosheets become worse with increasing electron energy. At the beginning of irradiation, some holes are formed on the surfaces of the WS2 nanosheets. With an increasing irradiation time, shrinkage of the nanosheets and rearrangement of the structure are appeared.When the electron beam irradiation WS2 nanosheets, the sulfur atom can be sputtered firstly and once the sulfur atoms that surrounded a tungsten atom are sputtered away, the remaining tungsten atom could be sputtered to form vacancies. When many sulfur atoms are sputtered, the remaining tungsten atoms become unstable. They easily moved and rearranged when they have enough energy.The graphene are irradiated by different electron energies, it seen that the damage to the graphene become worse with increasing electron energy. The edge of graphene begins to bend and shrink at the outset, with increasing irradiation time, the graphene edge suffers from increased bending and begins to transform into the carbon onion. The carbon onion is stable under low electron energy irradiation but is destroyed under high electron energy.The influence of gamma irradiation upon graphene is studied and the graphene experience the process of destruction-damage to saturated-recovery with increasing irradiation dose. In addition, gamma irradiation is able to increase the functional groups on the surface of graphene and improve its surface activity. The damages of graphene on gamma irradiation are mainly caused by the Compton effect.