Electronic properties of polypyrrole based TiO sub(2) nanofiber composite

In this work, Polypyrrole (PPy), Titanium dioxide nanofiber (TiO sub(2)-nf) are prepared by oxidative polymerization and hydrothermal process respectively. The PPy/TiO sub(2)-nf composite is prepared by in situ oxidative polymerization in the presence of pyrrole monomer and TiO sub(2)-nf. The nanocomposite and TiO sub(2)-nf are then characterized by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) techniques and XRD studies. Dielectric studies of PPy/TiO sub(2)-nf composite is carried out in the frequency range of 1 KHz-3 MHz at varying temperature and it shows anomalous behavior at 1MHz, where its value reaches to its minimum value of 13 at room temperature and this dip remains even at higher temperature. Impedance study is used to understand the grain and grain boundary effects of the material; frequency dependent ac conductivity has two regions separated at 1MHz, which is being explained by hopping conduction and Maxwell-Wagner type mechanism, respectively. copyright 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 40036.