Characterization of carbon nanotubes grown on Fe70Pd30Fe70Pd30 film

Carbon nanotubes have been synthesized by a LPCVD on nanocrystalline Fe–Pd film. CNTs are grown for 30min30min and 1 h respectively. From the SEM images, the diameter of these nanotubes varies from 40–80nm and the length is several micro-meter approximately. TEM observations suggest that the CNTs are multi-walled and the structure changes from ordinary geometry of CNTs to bamboo shaped. We have observed sharp G and D bands in the Raman spectra of these carbon nanotubes. Higher D-band is observed for the carbon nanotubes grown for longer time (1 h), showing that these nanotubes contain more amorphous carbon. The field emission measurements for these CNTs are also performed. For CNTs grown for longer time (1 h), a superior turn-on field of 4.88V/μm (when the current density achieves 10μA/cm2) is obtained and a current density of 29.36mA/cm2 can be generated at 9.59V/μm.