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Poly (vinylidene fluoride) (PVDF) is a chemical resistance polymer with high ferroelectric, piezoelectric and pyroelectric properties. PVDF has been chosen due to its unique properties compared with others in the polymers family and is used in a variety of sensors and transducers. A PVDF nanofiber membrane with relatively uniform morphology was prepared by an electrospinning technique. The surface morphology of the electrospun PVDF nanofibers was observed by scanning electron microscopy (SEM). The microstructure of electrospun PVDF nanofibers was characterized by Fourier Transform Infrared spectroscopy (FTIR) in the range 400 to 4000 cm-1. The functional groups were identified in the membrane. Infrared vibrational spectroscopy (FTIR + Raman) curves revealed a ferroelectric β-phase in the un-annealed membrane intrinsically. It showed that the electrospinning technique induce crystalline and polar β-phase by applying an electric field to the PVDF polymer solution during high solution jet stretching. The membrane (7 mm x5 mm) with full-face copper electrodes was produced to form a capacitor for testing.

In the past decade, hybrid organic-inorganic perovskites (HOIP) have emerged as the exotic materials for the futuristic photovoltaics. The viability of lowtemperature, solution-processed manufacturing and a unique blend of electronic and optical properties that has further indicated its goal towards a potential commercialization. This article clearly articulates the emergence of HOIPs and various challenges such as toxicity, hysteresis in these devices. Additionally, this chapter also makes an effort to highlight the advancements made in the perovskite materials for solar cells in the recent years, that include the Ruddlesden-Popper (RP) phase that has enabled us reach the power conversion efficiency of 28%. This phase is reportedly a lower dimensional structure than the conventional HOIP and exhibit better stability than the latter. This chapter also focuses to elucidate a few challenges of these RP phased HOIPs such as its synthesis, stoichiometry and process-ability in integrating the organic and inorganic entities.

Electrospun lead lanthanum zirconate titanate (PLZT)/polyvinylidene fluoride(PVDF) nanocomposite-based membranes were fabricated using a traditional electrospinning process. Scanning electron microscopy (SEM) was utilized to observe the surface morphology of the electrospun nanofiber membrane. The dielectric parameters of the nanocomposite membranes, such as permittivity, electric modulus, ac conductivity, and Impedance in the frequency range of 103 -106 Hz, were measured via an LCR measurement system. All-important electrical parameters were calculated from experimental measurements of capacitance and dissipation factor at ambient temperature. Frequency-dependent of, the above-cited parameters are presented.

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