Frequency-Dependent Conductivity and Dielectric Permittivity of Polyaniline/TiO2 Composites

• Published in: Ferroelectrics. Letters section 2008-01, Vol.35 (1-2), p.36-46
• Main Authors: MANJUNATH, S., ANILKUMAR, KOPPALKAR R., REVANASIDDAPPA, M., AMBIKA PRASAD, M. V. N.
• Format: Article
• Language: English
• Subjects: Composite materials; Condensed matter: electronic structure, electrical, magnetic, and optical properties; conductivity; Conductivity of specific materials; Dielectric loss and relaxation; dielectric permittivity; Dielectric properties of solids and liquids; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Electronic transport in condensed matter; Exact sciences and technology; Permittivity (dielectric function); Physics; polyaniline composites; TiO
• ISSN: 0731-5171; 1563-5228
• DOI: 10.1080/07315170801992435

Conducting polyaniline/Titanium di-oxide (PANI/TiO2) composites have been synthesized by insitu deposition technique by placing fine graded TiO 2 in polymerization mixture of aniline. The PANI/TiO 2 composites have been synthesized with various compositions viz., 10,20,30,40 and 50 wt % of TiO 2 in PANI. The ac conductivity was studied in the frequency range 10 2 -10 6 Hz. It is observed from the ac conductivity studies that the ac conductivity is found to be constant up to 10 5 Hz and there after it increases steeply which is a characteristic feature of disordered materials. The dielectric behaviour was also investigated in the frequency range 10 2 -10 6 Hz. It is observed from the dielectric studies that the value of dielectric constant decreases up to 20 wt % and later it increases rapidly up to 50 wt %. Similarly it is also seen that the tan δ values decreases rapidly up to 20 wt % and then increases up to 40 wt %, thereafter slowly increases up to 50 wt %. At higher frequencies these composites exhibit almost zero dielectric loss. The dimensions of TiO 2 particles in the matrix have a greater influence on the conductivity values and the observed dielectric values.