Synthesis, characterization and electrochemical performance of Nb2O5/cotton candy-PANI nanocomposite for supercapacitor applications

Abstract

The present work reports the synthesis and characterization of cotton candy-polyaniline (cc-PANI) and its nanocomposites with varying weight percentage of Nb2O5nanoparticles (5%, 10%, 20% and 30%) via in-situ polymerization method. The cc-PANI was successfully synthesized and demonstrated a distinctive nanostructure and spongy morphology. Incorporation of cc-PANI into the Nb2O5 matrix led to significant enhancement in the electrochemical performance of the resulting nanocomposite. The structural, functional, morphological and thermal properties of cc-PANI, Nb2O5 nanoparticles and Nb2O5/cc-PANI nanocomposites were examined using PXRD, FTIR, FESEM, and TGA/DTA analysis respectively. The cotton-candy morphology of cc-PANI enables rapid faradaic charge storage and improved conductivity, while Nb2O5 offers reversible Nb5+/Nb4+ redox activity and efficient ion intercalation. Integrating Nb2O5 into the cc-PANI matrix yields a strong synergistic effect, significantly enhancing the overall electrochemical performance. The electrochemical behaviour was evaluated using CV, EIS and GCD techniques in 1 M HCl electrolyte. Among the composites, the (30 wt%) Nb2O5/cc-PANI nanocomposite exhibit highest specific capacitance of 311.7 Fg-1 at a current density of 1 Ag-1, along with an energy density of 21.21 Wh kg−1 and a power density of 350.53 Wkg-1. Furthermore, is showed excellent cyclic stability with 82.23% capacitance retention over 2000 cycles. The results demonstrate the potential of cc-PANI based nanocomposites as efficient electrode materials for high performance supercapacitors, paving the way for future development of advanced energy storage materials.