Graphene-like coated steel tube via biased hollow cathode discharges

The inner surface of a narrow steel tube was coated with a very thick graphene-based (Gr-like) layer by biasing the tube in a Plasma Immersion Ion Implantation and Deposition (PIII&D) process. The outcomes indicate that a multilayer graphene film was grown in well-aligned columnar structures, showing a typical cauliflower-like character. Local gas feeding was found not only to overcome the discharge breakdown in such a small tube, but it...