The preparation of multi-wall carbon nanotubes by carbonizing low-density polyethylene composites

With the presence of catalysts, multi-wall carbon nanotubes (MWCNTs) were synthesized by carbonizing low-density polyethylene (LDPE) composites (as a model polymer of plastic waste). The results of the transmission electron microscopy shows that abundant MWCNTs with an almost homogeneous distribution in diameter are formed from carbonization of LDPE/organically modified montmorillonite (OMT)/nickel oxide (Ni₂O₃) composites. To our surprise, OMT plays an important role on the yield of MWCNT formation, and the MWCNT yield of LDPE/OMT/Ni₂O₃ is as about 5.5 times greater than that of LDPE/Ni₂O₃. X-ray diffraction and high resolution electron microscopy further demonstrate that Ni rather than Ni₂O₃ plays an active site role for the formation of MWCNTs.