Synthesis, Characterization and Enhanced Electrical Properties of Polyaniline-Tungsten Oxide Composites by in-situ Polymerization Technique

Abstract

The conducting polyaniline (PANI) and PANI doped with tungsten oxide (WO3) with varying wt% of WO3 are prepared by using in-situ chemical oxidative polymerization method. The X-ray diffraction it clearly reveals that pure PANI is amorphous whereas PANI/WO3 composites are in crystalline in nature. The electrical conductivity studied by four probe technique at 30–200°C. All the composites showed increase in conductivity values with the increase in WO3 content where the composite with 45% WO3 content showed highest value of 0.12 S/cm while the lowest conductivity of 0.06 S/cm was found in 5% WO3 content composite. The dielectric constant shows unusual response with respect to frequency with very high dielectric constant of 4.191X103 at 3X106 Hz for 45 wt% of WO3 in PANI, which attributes to the stronger localization of charge carriers and electrical relaxation processes.

Structural and electrical conductivity studies of Polyaniline - WO3 hybrid nanocomposites for gas sensing applications

“…In case of pure PANI, the electrical conductivity (σ) value was obtained to be 0.12 S/cm at room temperature. The value as obtained for emeraldine PANI sample is comparable with the conductivity values as reported in literature [19,20]. The DC electrical conductivity at room temperature for PWC10 to PWC40 composites exhibited the σ value of 0.083 S/cm to 0.035 S/cm respectively, whereas the WO3 nanoparticles indicated lower σ values of 1.4 x 10 -3 S/cm as shown in Figure 9a.…”

To investigate the crystalline grain size, morphological structure and microwave properties of PANI/PbO composite materials

“…The higher dielectric constant was observed for the PANI compared to the dielectric constant of the composite. The value of dielectric constant of PANI at 8.2x10 9 Hz is 9.58 and which decreases to 5.28 as frequency increased to 1.24x10 10 Hz. The value of dielectric constant of composite at 8.2x10 9 Hz is 4.79 and which decreases to 2.64 as frequency increased to 1.24x10 10 Hz.…”

“…The value of dielectric constant of PANI at 8.2x10 9 Hz is 9.58 and which decreases to 5.28 as frequency increased to 1.24x10 10 Hz. The value of dielectric constant of composite at 8.2x10 9 Hz is 4.79 and which decreases to 2.64 as frequency increased to 1.24x10 10 Hz. The maximum dielectric constant was observes to be 11.46 at 8.30X10 9 Hz for PANI.…”

“…These are applicable in displays, solar and sensing purpose which is primarily due to polyaniline that assist composite to attain semiconductive or conductive possessions [8][9]. From intense crystals are pemigrandline, emeraldine, nigranillin obtained from the oxidation with ammonium by sulphate hydrochloric acid and ammonium di-chromate [10]. The composite PANI/ PbO have huge properties like being unscented and the non toxics as well as posses extremely hardening, greater purity and high melting.…”