Low temperature catalyst-assisted pyrolysis of polymer precursors to carbon

[摘要] The aim of this work is to study the pyrolysis of polymer precursors to carbon at lower temperatures usinga catalyst. We have added different weight ratios of nickel acetate tetrahydrate (NiAc) and multi-walled carbon nanotubes(MWCNTs) as catalysts into two different precursors, polyacrylonitrile (PAN) and resorcinol–formaldehyde (RF), separately. PAN composite was stabilized whereas RF composite was dried under sub-critical conditions followed by pyrolysis carried out at different temperatures. To examine the effect of pyrolysis temperature and catalyst concentration, PAN- and RF-derived carbons were characterized by elemental analysis, X-ray diffraction, Raman spectroscopy, transmission electron microscopy, Fourier transform infrared spectrophotometer and small angle X-ray scattering, respectively. It was found that addition of NiAc facilitated similar carbon yield at much lower temperature than what was obtained without a catalyst. The addition of MWCNTs enhanced the crystallinity of carbon samples, which is otherwise possible only by higher heat treatment. Thisstudy clearly suggests adopting catalyst-assisted less energy intensive low temperature pyrolysis for polymer precursors tocarbon with better yield as well as crystallinity.

[学科分类] 材料工程

[关键词] Polyacrylonitrile;resorcinol-formaldehyde;pyrolysis temperature;carbon yield;crystallinity.