Carbon protrusions on PTFE surface prepared by ion irradiation and chemical defluorination

✍ Scribed by T. Kobayashi; M. Iwaki

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 246 KB
• Volume: 242
• Category: Article
• ISSN: 0168-583X
• DOI: 10.1016/j.nimb.2005.08.104

✦ Synopsis

A surface of PTFE was covered with small protrusions by ion-beam irradiation. In this study, we converted PTFE protrusions into carbon protrusions by a defluorination (carbonization) process using sodium vapor. The morphology, composition and structure were analyzed by SEM-EDX, Raman spectroscopy and TEM. The irradiated PTFE sheets were packed in evacuated glass tubes with a sodium block and kept at 473 K for 2-48 h. The samples were then rinsed in HCl and distilled water to remove NaF precipitates. The EDX measurement showed that the NaF precipitates were completely removed by washing, and the percentage of carbon atoms was controlled from 60% to 99% by the treatment. Raman spectra showed that graphite structures grow during the defluorination process. TEM micrographs showed that the protrusions have a bubble structure and are covered with a thin wall. The carbonized protrusions were conductive and grew perpendicular to the substrate.