摘要
Composite polymer electrolytes(CPEs) comprising poly(vinilydene fluoride-hexafluoro propylene), PVDF-coHFP and zinc triflate, Zn(CF3SO3)2 with varying concentrations of ZrO_2 nanofillers were prepared by solution casting technique with N,N-dimethyl formamide(DMF) as the common solvent. The polymer electrolyte specimen with the particular composition 75 wt% PVDF-co-HFP: 25 wt% Zn Tf + 7 wt% Zr O2 showed the highest conductivity of 4.6 × 10-4 S/cm at 298 K as confirmed from impedance measurements and favored by the rich amorphous phase of the CPE revealed from room temperature X-ray diffraction analysis(XRD). The electrical conductivity relaxation time and its distribution within the materials have been evaluated from the electric modulus M 2 and impedance Z" data which showed the occurrence of non-Debye type of relaxation phenomenon. The changes in the surface morphology of the CPEs were examined using scanning electron microscopy(SEM). The electrochemical stability window of CPE is found to be 2.6 V with a thermal stability up to 300 °C. An electrochemical cell has been fabricated based on Zn/MnO_2 electrode couple under a constant load of 1 MΩ and its discharge characteristics have been evaluated.
Composite polymer electrolytes(CPEs) comprising poly(vinilydene fluoride-hexafluoro propylene), PVDF-coHFP and zinc triflate, Zn(CF3SO3)2 with varying concentrations of ZrO_2 nanofillers were prepared by solution casting technique with N,N-dimethyl formamide(DMF) as the common solvent. The polymer electrolyte specimen with the particular composition 75 wt% PVDF-co-HFP: 25 wt% Zn Tf + 7 wt% Zr O2 showed the highest conductivity of 4.6 × 10-4 S/cm at 298 K as confirmed from impedance measurements and favored by the rich amorphous phase of the CPE revealed from room temperature X-ray diffraction analysis(XRD). The electrical conductivity relaxation time and its distribution within the materials have been evaluated from the electric modulus M 2 and impedance Z" data which showed the occurrence of non-Debye type of relaxation phenomenon. The changes in the surface morphology of the CPEs were examined using scanning electron microscopy(SEM). The electrochemical stability window of CPE is found to be 2.6 V with a thermal stability up to 300 °C. An electrochemical cell has been fabricated based on Zn/MnO_2 electrode couple under a constant load of 1 MΩ and its discharge characteristics have been evaluated.
基金
financially supported by the National Centre for Nanoscience and Nanotechnology,University of Madras for SEM analysis and financial assistance received in the form of a research grant