Effect Nd2O3 content on electrochemical performance of polyaniline/Nd2O3 composites

Polyaniline/neodymium(III) oxide (PANI/Nd2O3) composites were synthesized by in situ chemical oxidative polymerization method, and the new electrode materials were used for supercapacitor. The composites were characterized physically by scanning electron microscope (SEM), Fourier transform infrared spectra (FTIR) and X-ray diffraction (XRD). SEM, IR and XRD results showed the existence of interactions between PANI and Nd2O3. The electrochemical capacitance performance of the composites was investigated by cyclic voltammetry, galvanostatic charge-discharge tests and ac impedance spectroscopy with a three-electrode system in 6M KOH solution. Cyclic voltammetry and galvanostatic charge/discharge tests proved that the addition of Nd2O3 enhanced the capacitance of the composites. However, the conductivity of the composites decreases with increasing the amount of Nd2O3. Electrochemical impedance tests manifest that the charge-transfer resistance of the composites is smaller than that of the pure PANI, which indicates the addition of Nd2O3 could lower resistance and facilitate the charge transfer of the active materials. All results support that Nd2O3 has a significant contribution to the performance of PANI and makes the composites have more active sites for faradiac reaction and larger specific capacitance than pure PANI. Copyright (c) 2014 John Wiley & Sons, Ltd.