Pyrolysis of waste polypropylene for the synthesis of carbon nanotubes

Waste polypropylene (PP) is used as precursor for synthesizing multi-walled carbon nanotubes (MWCNTs) by single stage chemical vapor deposition (CVD) method using nickel as catalyst. The pyrolytic degradation of PP to MWCNT was achieved by exposing the catalyst and precursor to temperature 600,700 and 800 ◦C under argon and hydrogen atmosphere for an hour. The resultant carbon was purified and characterized by XRD, Raman scattering, SEM, TEM and HRTEM. All the analysis confirmed the graphitic nature and multi-walled morphology of the CNT. Moreover the MWCNT was found to exhibit high transmittance to visible light up to 85% at 550 nm, comparable to that of typical ITO films (90%), suggesting that MWCNTs can be used for optoelectronic devices. The present work could be employed for synthesizing CNTs, having wide range of applications, and for environment protection as well since waste plastic is being used.