Portal de Periódicos da CAPES

Electrodeposition and pseudocapacitive properties of tungsten oxide/polyaniline composite

2011; Elsevier BV; Volume: 196; Issue: 10 Linguagem: Inglês

10.1016/j.jpowsour.2011.01.073

1873-2755

Ben-Xue Zou, Ying Liang, Xiaoxia Liu, Dermot Diamond, King‐Tong Lau,

Advanced Sensor and Energy Harvesting Materials

Composite films of tungsten oxide (WO3) and polyaniline (PANI) have been electrodeposited by cyclic voltammetry in a mixed solution of aniline and precursor of tungsten oxide. Surface morphology and chemical composition of WO3/PANI composite are characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The influence of H2O2 on the electrodeposition of WO3/PANI composite film is also investigated. Cyclic voltammetry (CV), chronopotentiometry (CP) and electrochemical impedance spectroscopy (EIS) results show that WO3/PANI composite film exhibit good pseudocapacitive performance over a wide potential range of −0.5 to 0.7 V vs. SCE with the specific capacitance of 168 F g−1 at current density of 1.28 mA cm−2 and energy density of 33.6 Wh kg−1, which is 91% higher than that of similarly prepared PANI (17.6 Wh kg−1). An asymmetric model capacitor using WO3/PANI as negative and PANI as positive electrodes over voltage range of 1.2 V displays a specific capacitance of 48.6 F g−1 and energy density of 9.72 Wh kg−1 at the power density of 53 W kg−1, which is two times higher than that of a symmetric capacitor modeled by using two PANI films as both positive and negative electrodes.