Synthesis, Characterization and D. C. Conductivity Studies of Polypyrrole/Molybdenum Trioxide Composites

In-situ polymerization of pyrrole (PPy) was carried out with molybdenum trioxide (MoO3) in the presence of oxidizing agent ammonium persulphate to synthesize polypyrrole/molybdenum trioxide composites (PPy/MoO3) by chemical oxidation method. The PPy/MoO3 composites were synthesized with various compositions viz., 10, 20, 30, 40 and 50 wt % of MoO3 in pyrrole. The powder X-ray diffraction (XRD) spectrograph, suggests that they exhibit semi-crystalline behavior. The Fourier Transform Infra-Red Spectroscopy (FTIR) reveals the stretching frequencies are shifted towards higher frequency side. The surface morphologies of these composites using Scanning Electron Microscopy (SEM), show that MoO3 particles are embedded in PPy chain to form multiple phases. The D.C. conductivities were studied in the temperature range from 30-200 degrees C.The values of the conductivity increase up to 40 wt % MoO3 in PPy and decreases thereafter. This percent weight is the percolation threshold for these composites. The composites obey percolation theory. The dimensions of molybdenum trioxide particles in the matrix have a greater influence on the conductivity values.