Chitosan-ZnO/polyaniline hybrid composites: Polymerization of aniline with chitosan-ZnO for better thermal and electrical property

A new chitosan-ZnO/polyaniline (CPA-ZC/ZO) hybrid composite is prepared by single-step in situ oxidation polymerization of aniline hydrochloride in the presence of (NH4)2S2O8 and chitosan-ZnO (CS-ZO). The structural and morphological features of CPA and CPA-ZC/ZO hybrids were analyzed using FT-IR, UV-vis, SEM, EDXS and XRD analysis. The chemical bonding established between CPA and CPA-ZC/ZO, confirmed by FT-IR, is likely to be responsible for the enhanced chemical stability. The UV-vis spectra of CPA-ZC/ZO were found to red/blue shift as compared to those CPA molecular chains. From SEM observation, the ratio of ZnO nanoparticles to CPA altered the morphology of the hybrids from granular to plate like structure, which was confirmed by EDXS. The XRD patterns of the as-prepared hybrids show the wurtzite structure of ZnO is well maintained after the impregnation of CPA. Thermal property was studied using TG/DTA analysis shows the residual weight (TGA curves) and its weight derivative (DTA curves) of the CPA-ZC/ZO are more stable than CPA and CS-ZO. In addition, the cyclic voltammetry on the obtained hybrid materials revealed that the plate-like structure was more advantages for the electrochemical stability. Overall, the results show that the introduction of the ZnO nanoparticles into CPA matrix enhanced the thermal and electrode stability.