Synthesis of branched, nano channeled, ultrafine and nano carbon tubes from PET wastes using the arc discharge method

Upcycling polymer wastes into useful, and valuable carbon based materials, is a challenging process. We report a novel catalyst-free and solvent-free technique for the formation of nano channeled ultrafine carbon tubes (NCUFCTs) and multiwalled carbon nanotubes (MWCNTs) from polyethylene terephthalate (PET) wastes, using rotating cathode arc discharge technique. The soot obtain from the anode contains ultrafine and nano-sized solid carbon spheres (SCS) with a mean diameter of 221. nm and 100. nm, respectively, formed at the lower temperature region of the anode where the temperature is approximately 1700. �C. The carbon spheres are converted into long "Y" type branched and non-branched NCUFCTs and MWCNTs at higher temperature regions where the temperature is approximately 2600. �C, with mean diameters of 364. nm and 95. nm, respectively. Soot deposited on the cathode is composed of MWCNTs with a mean diameter of 20. nm and other nanoparticles. The tubular structures present in the anode are longer, bent and often coiled with lesser graphitization compared to the nanotubes in the soot on the cathode. � 2014 Elsevier Ltd.