Irradiation Property Of WS₂Nanotubes And Carbon Nanotubes

WS₂nanomaterials have better performance than traditional WS₂materials, sothey have a wide range of application areas. For example, WS₂nanotubes haveexcellent lubricating properties under the vacuum environment. They are suitablefor satellite and aircraft, which require lubrication and work in space environment.Therefore, the study of WS₂nanotubes irradiated by various rays and particles inspace becomes very important.This paper mainly studies the effect of gamma ray, electron beam and ion beamirradiation on WS₂nanotubes/powders. Meanwhile, we add some carbon nanotubesirradiation experiments, comparing the radiation hardness of WS₂nanotubes andcarbon nanotubes.The WS₂nanotubes/powders, carbon nanotubes are irradiated by gamma ray.The irradiation doses are200kGy,2MGy. The study finds that the effect of gammairradiation on carbon nanotubes is very obvious. With the increase of the irradiationdose, carbon nanotubes experience the process of destruction-damage tosaturated-recovery. However, WS₂nanotubes are barely affected by theγ-irradiation. The crystallinity of WS₂powders becomes better after irradiation.The ability of anti-gamma irradiation of WS₂nanotubes is stronger than that ofcarbon nanotubes.The WS₂nanotubes/powders, carbon nanotubes are irradiated by electron beam.The results show that the WS₂nanotubes are destroyed from the outer layer to theinside. The displaced atoms can leave the irradiated area by sputtering events or bydiffusive migration along the shells and the inner hollow. The smaller tubes have alower stability. The stability of the tube increases after the central hollow is closed.The asymmetric irradiation can lead to a bending of the tube and irradiation ofcrossed WS₂nanotubes is shown to give rise to nanotube welding. In addition,electron irradiation causes the change of WS₂nanotubes into a polycrystallinestructure. The dangling bonds on the surface increase. When the electron beamstrikes the carbon nanotube, first the center hole is closed and then shrink, thecarbon onion structure is appeared on the surface. The ability of anti-electronirradiation of WS₂nanotubes is stronger than that of carbon nanotubes. Thedestruction of the electron beam on WS₂powders is a sputtering event. The WS₂piece is stripped layer by layer.The WS₂nanotubes/powders are irradiated by ion beam. The irradiation dosesare1015,1016,1017ions/cm2. The effect of ion irradiation on WS₂nanotubes is veryobvious. With the increase of the irradiation dose, the thickness of the sputteredlayer of WS₂nanotubes increases. The ion irradiation can make the WS₂react withthe oxygen which can be chemisorbed on the defects and dangling bonds of thenanotube to form WO3and the content of WO3increases with the increase of the irradiation dose. Similar to the electron irradiation, ion irradiation can also lead tothe fact that the unsaturated dangling bonds on the edge of the nanotube increase,which can increase the surface activity of nanotube. The surface of the WS₂sheetforms a pit under the high dose irradiation due to the ion sputtering effect.