Abstract
Here, we discuss one of the simplest approaches for chemical functionalization of in-situ prepared polyaniline (Pani) and its nanocomposites with multi-walled carbon nanotubes (MWCNT) and graphene (GN) in chlorosulphonic acid. The effect of polymerization and functionalization was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis, Field emission scanning electron microscopy (FESEM) and electro-thermal analysis. Results also revealed the presence of pi-pi interactions between Pani and carbon allotropes leading to the formation of charge-transfer complexes. This strong pi-pi interaction significantly increased the resultant electrical conductivity, stabilizing them as well. Further, theirs back to back sulphonation in chlorosulphonic acid significantly enhanced the solubility in one way but caused a heavy loss in conductivity conversely. The thermoelectric properties of the as-prepared nanocomposites were investigated as a function of MWCNT and GN contents. It was observed that as-prepared Pani/GN nanocomposites showed a greater electrical conductivity as well as an improved thermal stability in terms of DC electrical conductivity retention under isothermal and cyclic ageing conditions compared with Pani/MWCNT and Pani. Finally these oxidative products were also studied for their sensing response towards amine to detect whether the particular compound is either 1 degrees, 2 degrees, or 3 degrees amine. (C) 2019 The Authors. Publishing services by Elsevier B.V. on behalf of Vietnam National University, Hanoi.