Highly conducting PANI- fMWNT composites with exceptional crystallinity and enhanced thermal stability for potential applications

Abstract

Here we report, the synthesis and characterization of the thin film of polyaniline-functionalized multiwalled carbon nanotube composite with exceptional electrical conductivity, excellent crystallinity and improved thermal stability. In this study, the multiwalled carbon nanotubes were functionalized using formaldehyde through an electrophilic substitution reaction and methylol groups (-CH2OH) attached to the sidewalls of the nanotubes. A significant dispersivity of polyaniline-multiwalled carbon nanotube composites was achieved as a result of the functionalization. The thin film of polyaniline-functionalized multiwalled carbon nanotube composite was prepared via the doping-dedoping-redoping process. The structural, morphological, thermal and conductivity studies of the synthesized polyaniline-functionalized multiwalled carbon nanotube composite samples were carried out using various characterization tools. The thin film sample shows an enhanced electrical conductivity of 1991 S/cm, which is pretty high among the reported values for polyaniline-carbon nanotube composites. It also exhibits an excellent crystallinity of 84.44%, the highest value ever reported. The thermal stability of the thin film sample is very high compared to the polyaniline sample. The charge transfer mechanism in the synthesized samples was investigated using the three-dimensional variable range hopping model. The ANOVA and regression analysis was performed to assess the validity of the model.