Deposition of Pt Nanoparticles on Oxygen Plasma Treated Carbon Nanotubes by Atomic Layer Deposition

Platinum nanoparticles were formed on oxygen plasma treated carbon nanotubes by atomic layer deposition (ALD). The treatment time of oxygen plasma generated by a microwave plasma enhanced chemical deposition system varied at 5 s to 20 s under a power of 600 W. The reaction cycle number was controlled at 50-125 and the length of pulse time for Pt precursor, O(2) and N(2) were set at 1 s, 5 s and 20 s, respectively. It was observed that formation of uniform and well distributed Pt nanoparticles was achieved. Furthermore, the growth rate of Pt nanoparticles could be controlled by altering the reaction cycle number and oxygen plasma treatment time. X-ray photoelectron spectroscopic analysis indicated that oxygen plasma could graft oxygen-containing functional groups to the CNTs surface, to act as the nucleation sites for growth of Pt nanoparticles.