Structural changes and electrical properties of nanowelded multiwalled carbon nanotube junctions

This study proposes an efficient approach that uses a 1064 nm continuous fiber laser to achieve nanoscale welding of crossed multiwalled carbon nanotubes (MWCNTs). We investigate the effects of laser irradiation time (from 1 to 6 s) on the structure changes and the welding quality of crossed MWCNTs using a scanning electron microscope, transmission electron microscope, and Raman spectroscopy. The experimental results demonstrate that (1) after 2 or 3 s laser irradiation, moderate temperature of MWCNTs can be formed and can cause a higher degree of graphitization and (2) the degree of graphitization and effective contact of nanowelded MWCNT junctions strongly affects its electrical properties.