Observation of diffusion induced dislocations on single Crystalline Au nanowhiskers during interdiffusion studies

Understanding and control of the defects is a crucial matter in materials science, by analyzing the experimental results, we aim controlled microstructure on nanomaterials, which will open a door for us to optimize the material properties. Therefore, during the interdiffusion studies on bimetallic Au/Fe nanowhiskers we have been coming across so many defect formations and naturally studying them to be able to explain the microstructural changes and diffusion characteristics as well as control and optimize the nanostructures.

Au nanowhiskers were grown on a cold rolled Mo substrate at 750 °C and subsequently a layer of Fe deposited on Au whiskers at room temperature using Molecular Beam Epitaxy (MBE). Au forms random growth of single crystalline nanowhiskers and the layer of Fe shows a mixed crystallinity (Figure 1). After the heat treatments (at 500°C 2h and 600°C 2h), bimetallic nanowire system HRTEM investigations carried out and formation of edge dislocations which later lead to diffusion induced grain boundary formation were observed (Figure 2-3).