Nickel modification of carbon nanotubes grown on graphite for electrochemical sensors

Nickel modified carbon nanotubes on graphite substrate were investigated for constant-potential amperometric detection of l-asparagine. Both entangled and aligned carbon nanotubes directly grown on graphite by thermal chemical vapor deposition were used for making the electrodes. Nickel was applied on the carbon nanotubes by electrodeposition. The electrodeposited nickel on the entangled carbon nanotube electrodes dramatically enhanced the analytical response, while on the aligned carbon nanotube electrodes and on the graphite electrodes without the carbon nanotubes it was considerably less effective. The entangled carbon nanotube film formed from Co catalyst was concluded as a promising underlayer for electrodepositing nickel nanoparticles for detecting l-asparagine and also possibly other chemicals and biochemicals.