Carbon Nanofoam Formed by Laser Ablation

Foam-like carbon (carbon nanofoam, CNF) which belongs to the porous carbon family is formed by pulsed laser ablation of graphite in liquid nitrogen. Each bubble is about 3–10 nm in size and has a layered structure with typically one to four graphene layers. The CNF forms nanoparticles of about 100 nm in size. CNF encapsulating platinum nanoparticles (Pt@CNF) is formed when a mixture of graphite, platinum, and hexadecanoic acid is used as a target. Each bubble encapsulating a platinum nanoparticle is approximately 15±4 nm in diameter and contains typically 6±3 graphene walls. The platinum nanoparticles in the CNF are 9±4 nm in diameter. The annealing of the Pt@CNF at 300 °C for a week in vacuum reveals that the CNF effectively prevents the platinum nanoparticles from aggregating.