Investigation of the effect of ionizing radiation on the structural and conductive characteristics of Ni nanostructures

Abstract

The work presents the changes in the structural and conductive properties of Ni nanostructures. B2+, Ca5+, Fe7+ ions were used as the bombarding beams. Fluence irradiation constitutes 1010, 1011 и 5 × 1011 ion/cm2. The use of ions B2+, Ca5+, Fe7+ allows to simulate the effects of irradiation with different energy losses, as well as the course of the process of defects formation in structures. It has been established that in the samples irradiated with B2+ and Ca5+ ions, the main structural changes are associated with amorphization or texture reorientation, and for samples irradiated with Fe7+ ions, the formation of low intense peaks characteristic of FeNi is observed. It has been established that an increase in the degree of crystallinity indicates a positive effect of calcium ions on the crystal structure, which consists in the partial annealing of defects and the removal of stresses and distortions in the crystal lattice. A slight decrease in the degree of crystallinity during irradiation with iron ions can be explained by the processes of implantation and knocking out of nickel atoms from lattice sites, which leads to the formation of impurity inclusions in the form of the FeNi phase, the content of which increases with irradiation fluence. The formation in the structure of amorphous inclusions and partial destruction of the walls of nanotubes under the action of irradiation with boron ions leads to a sharp decrease in the degree of crystallinity and conductive properties of nanotubes.