One step synthesis of multiwalled carbon nanotube/gold nanocomposites for enhancing electrochemical response

The synthesis of multiwalled carbon nanotube (MCWNT)/gold nanocomposites for enhancing electrochemical response was discussed using citrate reduction method. It was found that the size of gold nanoparticles coated on carbon nanotubes was in the range of 20 to 24 nm with the average of 22 nm when 1.5 mL of sodium citrate was applied for the respective preparation, while the range was 9 to 13 nm with the average of 12 nm when 4 mL of sodium citrate was added to the relative reaction. The premixing of carbon nanotubes with HAuCl 4 solution could efficiently induce the adsorption of HAuCL 5molecules on the nanotubes, leading to the growth of gold nanoparticles on the side wall of the carbon nanotubes when the sodium citrate was subseqently added. The results show that the MWCNT-gold nanocomposites at the electrode surface efficiently accelerate the electron transfer at the glassy carbon electrode (GCE) and enhance the respective electrochemical performance.