Structural and Electrical Conductivity Studies of PVDF-HFP Film Filled with Tio2 and Nacl for Polymer Semiconductors

As prospective electrolyte membranes are fabricated using a conducting copolymer of poly (vinylidene difluoride-co-hexaf luoropropy lene) (PVDF-HFP) by a solution casting method. The prepared membranes were filled with an electrical conductor (NaCl) and semiconductor (TiO2) nanopowder in this method. The assimilated membranes were analytically characterized by scanning electron microscope (SEM) for surface morphology and X-ray diffraction (XRD) for crystalline nature of the TiO2 nanopowder present in the prepared membrane. The FTIR confirms the structural analysis of the copolymer and the NaCl and TiO2 incorporation nature into the PVDF-HFP membrane. Electrochemical stability of the fabricated membrane of PVDF-HFP was performed using thermo-gravimetric analysis (TGA). The cyclic voltammetric analysis conducted the charge and discharge tests of the filled and unfilled membrane. The addition of nano TiO2 particles and NaCl to the copolymer membrane was found to reduce the PVDF-HFP membrane's porousness and improve the ion conductivity and electrolyte/electrode interfacial stability of the filled membrane.

Catalysis of the Thermal Decomposition of Transition Metal Nitrate Hydrates by Poly(vinylidene difluoride)

Poly(vinylidene difluoride) (PVDF) doped with transition metal nitrate hydrates are cast into thin films giving a high β-phase content. Analysis of the thermal behavior of the doped PVDF shows that the decomposition of the metal (II) nitrate hydrates to metal (II) oxides is catalyzed by the PVDF, as evidenced by reduction in the decomposition temperature by as much as 170 °C compared to the pure metal salts. In contrast, there is little to no apparent catalysis for the decomposition of the metal (III) nitrate hydrates. The FTIR spectra of the gas phase decomposition products show H2O and NO2 are the major components for both PVDF-doped material and the pure metal nitrate hydrates. A mechanism for the role of PVDF is proposed that uses the internal electric field of the ferroelectric phase to orient the nitrate ions and polarize the N-O bonds.