Thermal stability and electrochemical performance of Polyaniline/Pr6O11 composites

Abstract

In order to describe the influence of Pr6O11 on thermal and electrochemical performance of polyaniline (PANI), PANI/Pr6O11 composites were synthesized by in situ polymerization in the presence of sulfosalicylic acid (as dopant). The composites obtained was characterized by scanning electron microscope, Fourier transform infrared spectra, and X‐ray diffraction. The thermal stability of the composites was investigated by thermogravimetry and derivative thermogravimetry. Finally, the comparative analysis on the electrochemical properties of PANI/Pr6O11 composites electrodes, such as cyclic voltammetry, electrochemical impedance spectroscopy, and constant current charge–discharge test, was conducted under similar conditions. Scanning electron microscope, infrared, and X‐ray diffraction results show that interaction exists between PANI and Pr6O11, and the composites are more crystalline than pure PANI. Thermogravimetry and derivative thermogravimetry analyses indicate that PANI/Pr6O11 composites and pure PANI have similar thermal stability. Moreover, the studies regarded to capacitive properties show that the electrochemical performance of the composites is improved greatly when Pr6O11 is added in small amount. However, with increasing the amount of Pr6O11, the electrochemical performance of the composites become worse, which indicates a large amount of Pr6O11 has a negative effect on the capacitance. These results suggest that PANI is still in the conductive form after inserting the Pr6O11, and the capacitance performance of PANI can be improved only by a low percentage of Pr6O11. Copyright © 2013 John Wiley & Sons, Ltd.