Improvement in structural and electrical properties of cuprous oxide-coated multiwalled carbon nanotubes

Abstract

In the present work, cuprous oxide (Cu₂O) nanoparticles are coated on multi-walled carbon nanotubes (MWCNTs) using Fehling’s reaction. The coating of Cu₂O nanoparticles on the nanotubes was confirmed by SEM and X-ray diffraction (XRD) spectra. The calculated I _D/I _G ratio of Cu₂O (using 3% CuSO₄ by wt)-coated MWCNTs by Raman spectra is found to decrease to 0.94 as compared to 1.14 for pristine MWCNTs. It shows that the presence of Cu₂O nanoparticles on nanotubes decreases the inherent defects present in the form of some pentagons/heptagons in the honeycomb hexagonal carbon atoms in the structure of graphene sheets of MWCNTs and increases the crystalline nature of MWCNTs, which is also confirmed by the XRD peaks. Whereas the value of I _D/I _G ratio increases to 1.39 for sample 2 (using 5% CuSO₄ by wt), which represents the structural deformation. Moreover, the electrical conductivity of MWCNTs was increased by 3 times after coating the nanotubes with Cu₂O (using 3% CuSO₄ by wt).