Kamlesh Pandey

Dielectric and Ion Transport Studies in [PVA: LiC2H3O2]: Li2Fe5O8 Polymer Nanocomposite Electrolyte System

The present work deals with the findings on optical and ion transport behavior in a ferrite-doped polymer nanocomposite electrolyte system, namely, [(100 − x) PVA + xLiC2H3O2]: yLiFe5O8. This polymer electrolyte system has been characterized by SEM, DSC, IR and C-V measurements. The addition of filler seems to disturb the crystalline nature of the host matrix while the doping of salt shows a similar structure, but with a separate entity in SEM images. DSC studies reflect the interaction of the salt/filler with polymer with a change in morphology of the composite system. These results are well-corroborated by IR data. The effect of salt or filler in the enhancement of the a.c. conductivity of nanocomposite polymer electrolyte (NCPE) as well as dielectric relaxation behavior has been investigated with the help of impedance spectroscopy data. The a.c. conductivity of nanocomposite polymer electrolytes is seen to be best described by the universal power law.

Effect of Plasticizers on Structural and Dielectric Behaviour of [PEO

Improvements in ion transport property of polyethylene-oxide- (PEO-) based polymer electrolytes have been investigated, using different types of plasticizers. The effects of single and coupled plasticizers [i.e., EC, (EC

Study of structural and dielectric behaviour on carbon nano tube dispersed {xPVF: (1 − x)CH3COONH4} electrolyte

In the present work, improvement in ion transport property of polyvinyl formal (PVF)-based nanocomposite polymer electrolytes has been studied upon dispersal of multiwall carbon nanotube (MWCNT) filler. Nanocomposite polymer electrolyte (NCPE) films of xPVF: (1 − x)CH3COONH4 (ammonium acetate) were prepared by solution cast technique. The formation of nanocomposite has been ascertained by X-ray diffraction (XRD) pattern, which also shows that doping of salt increases amorphousness through polymer salt complexation. Changes in surface morphology have been observed in optical microscopy and Scanning Electron Microscopic (SEM) images. Variation of dielectric constant, dielectric loss, tangent loss and modulus spectra with the change in frequency and temperature were studied with the aid of impedance spectroscopy.

Effect of Different Filler Groups on Ionic Behavior of PVdF Gel Electrolyte System

In the present work, improvement of ion transport property in poly vinylidene fluoride (PVdF)based polymer electrolytes, have been investigated using different groups of fillers. The effect of filler, on structural and electrical behavior of electrolyte was studied by XRD and impedance spectroscopy. Improvement in amorphous nature and ionic conductivity has been observed for PVdF based polymer electrolytes dispersed with different filler particles. Argond Plot shows dispersive nature of relaxation time and hopping mechanism appears to be responsible for ionic conduction of the composite polymer electrolyte.

Performance of ferrite fillers on electrical behavior of polymer nanocomposite electrolyte

Dispersal of nanofillers in polymer electrolytes have shown to improve the ionic properties of Polyethylene oxide (PEO)-based polymer electrolytes in recent times. The effects of different nanoferrite fillers (i.e., Al–Zn ferrite, Mg–Zn ferrite, and Zn ferrite) on the electrical transport properties have been studied here on the composite polymer electrolyte system. The interaction of salt/filler with electrolyte has been investigated by XRD studies. SEM image and infrared spectral studies give an indication of nanocomposite formation. In conductivity studies, all electrolyte systems are seen to follow universal power law. Composition dependence (with ferrite filler) gives the maximum conductivity in [93PEO–7NH4SCN]: X ferrite (where X = 2% in Al–Zn ferrite, 1% Mg–Zn ferrite, and 1% Zn ferrite) system.

Natural photosensitizers for solid-state dye sensitized solar cell

Natural dye sensitized solar cells (DSSC) have been widely investigated as a next generation solar cell because of their simple structure and low manufacturing cost. In the present work betacyanin dye responsible for the red color of many fruits and leaves having favorable absorption spectra with the solar spectrum has been used in fabrication of solid state dye sensitized solar cell. A Nanocomposite polymer electrolyte consisting of Poly vinyl alcohol (PVA), Lithium acetate, Ethylene carbonate (EC) and Propylene carbonate (PC) with TiO2 filler was used as a solid state thin film electrolyte for betacynin based Dye Sensitized Solar cell. The nanocomposite polymer was complexed with ammonium iodide and iodine crystals were added to the polymer electrolyte. The DSSC with the nanocomposite polymer electrolyte showed good photovoltaic performnance including short circuit photocurrent density (Jsc) 9.8 mA cm-2, the opencircuit volyage (Voc) 0.435 V, the fill factor (ff) of 52% and the conversion effeciency (η) of 2.2% under AM 1.5.

Synthesis and characterisation of PVdF-{(NH 4 ) 2 [C 4 H 8 (COO) 2 ]}: CNT gel electrolyte for Lt fuel cell application

In the present work, improvement of ion transport property in poly (vinylidene) fluoride (PVdF) - based polymer electrolytes for the use of low temperature fuel cell application have been investigated using CNT as fillers. The effect of filler, on structural and electrical behavior of electrolyte were studied by different experimental tools namely, XRD, Optical microscopy, impedance spectroscopy, and dielectric relaxation measurement. Improvement in amorphous nature and ionic conductivity has been observed for PVdF based polymer electrolytes dispersed with CNT filler particle. Dielectric plots show dispersive nature of relaxation time and hopping mechanism appears to be responsible for ionic conduction of the nanocomposite polymer electrolyte.

Synthesis and characterization of PVdF/ PEO blend based polymer electrolyte for DSSCs application

A blend of poly (vinyldiene fluoride) and PEO hybrid composite film was prepared via sol gel technique. The properties of the blend was studied, by morphological measurement such that optical microscopy and SEM image. It show that the change in crystalline structure of the blend composite system. This is an indication of the less interaction between PVdF and PEO. The electrical properties shows the effect of die as the increases in conductivity as compared to the pristine polymer electrolyte.