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Polyvinylchloride (PVC)/nickel oxide (NiO)/tungsten oxide (WO3) nanocomposite films were prepared via solution casting technique. The crystallinity, morphology, and the analysis of dispersion state of PVC/NiO/WO3 nanocomposite was carried out using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The dielectric studies of nanocomposite films were investigated and a maximum dielectric constant of 2.3 with dielectric loss (tan δ) of 2.4 was attained. The EMI shielding studies were carried out in the X and Ku-band frequency range (8 GHz-18 GHz). The maximum SE of 15.78 dB in X-band and 12.05 dB in Ku-band was achieved for 75/20/5 compositions of the PVC/NiO/WO3 nanocomposite. [ABSTRACT FROM AUTHOR]

Green synthesis methods have attracted enormous research interest as replacements for dangerous chemicals due to their abundance and eco-friendliness. The remarkable properties of green synthesized materials include environmental friendliness, high abundance, antimicrobial, antioxidant and biodegradability. The integration of green synthesized materials in electronic devices not only enhances the economic benefit of natural waste resources but also conserves our environment. This review article is dealing with the current research efforts in green synthesized materials trends, challenges and their potential applications in sensors, actuators, energy storage and energy generation. [ABSTRACT FROM AUTHOR]

The hexagonal boron nitride nanoparticles (h-BNNPs) reinforced flexible polyvinylidene fluoride (PVDF) nanocomposite films were prepared via a simple and versatile solution casting method. The morphological, thermal and electrical properties of h-BNNPs/PVDF nanocomposite films were elucidated. The electromagnetic interference (EMI) shielding properties of prepared nanocomposite films were investigated in the X-band frequency regime (8–12 GHz). The EMI shielding effectiveness (SE) was increased from 1 dB for the PVDF film to 11.21 dB for the h-BNNPs/PVDF nanocomposite film containing 25 wt% h-BNNPs loading. The results suggest that h-BNNPs/PVDF nanocomposite films can be used as lightweight and low-cost EMI shielding materials. [ABSTRACT FROM AUTHOR]

Polymer/inorganic nanocomposites comprising of hydroxypropyl methylcellulose and polyvinyl alcohol as a polymer matrix and unique combination of graphene oxide and zinc oxide nanoparticles as fillers have been prepared using colloidal processing technique and characterized using various analytical methods. The dielectric properties of the nanocomposites are investigated using impedance analyzer. The nanocomposites show improvement in the dielectric properties compared to hydroxypropyl methylcellulose/polyvinyl alcohol (50/50) blends, which results from the homogeneous dispersion of fillers into the polymer matrix. The results indicate that these nanocomposites have a potential to meet the technological demands of high-k dielectrics and/or embedded capacitors. [ABSTRACT FROM AUTHOR]

Using organic dyes Coumarin-503 (C503) and Coumarin-540 (C540) as donor and acceptor dyes, respectively, and Nd-YAG as pumping source (355 nm), an energy transfer-distributed feedback dye laser (ETDFDL) was constructed and its characteristics studied. Theoretical studies such as critical transfer radius (Ro), critical concentration (Co), and half quenching concentration (C1/2) were carried out using the absorption and fluorescence spectra of donor and acceptor dyes. On varying the input pump energy to the nanoparticle-incorporated ETDFDL and keeping the acceptor and donor dye concentrations constant, the lasing output obtained was found to be higher than that without the use of nanoparticles. This enhancement was due to the size, shape, and coupling between nanoparticles with the dye mixture. Tunability in the range of 435–553 nm was obtained for both donor (C503) and acceptor (C540) DFDL as a function of the angle of interfering beams of the pump laser. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol/potassium chromate (K2CrO4) composite films were prepared by solution casting technique using distilled water as a solvent, and were further investigated using Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, X-ray diffraction, thermogravimetric analysis, optical microscopy, scanning electron microscopy, and dielectric measurements. Microscopic studies reveal that K2CrO4was homogenously mixed with polyvinyl alcohol matrix due to interfacial interaction between polyvinyl alcohol and K2CrO4. The composite films showed very high dielectric constant and relatively low dielectric loss. Hence, such composite materials with improved dielectric properties could be useful for fabrication of electrical charge storage device. [ABSTRACT FROM AUTHOR]

Graphene oxide was synthesized using modified Hummers method. The preparation of polyvinylchloride/graphene oxide nanocomposites was carried out using colloidal processing. The morphology of polyvinylchloride/graphene oxide nanocomposite confirms that graphene oxide was uniformly distributed within the polyvinylchloride matrix indicating complete exfoliation of graphene oxide. Significant improvement in the microhardness of the nanocomposite was observed as compared to neat polyvinylchloride. The impedance spectroscopy of nanocomposites was carried out in the frequency range (50 Hz to 35 MHz) and temperature range (80–150°C). Thus, based on the results obtained, we found that polyvinylchloride/graphene oxide nanocomposites hold great promise in many potential applications such as an electrode material for supercapacitors. [ABSTRACT FROM PUBLISHER]

Zinc selenide (ZnSe) nano particles were synthesised by chemical route at 205°C and it was confirmed by powder X-ray diffraction analysis. Utilizing the synthesised nano particles as the source material, ZnSe thin films were deposited at various substrate temperatures (Room Temperature (RT), 150°C, 250°C, 350°C and 450°C) employing electron beam evaporation method. X-ray diffraction results show that the prepared films are amorphous in nature. Raman spectral analysis confirmed the formation of ZnSe. Optical properties were studied using UV-Vis transmittance spectrum. Film prepared at RT possesses relatively high transmittance. Electrical studies carried out show that the ZnSe thin film belongs to p-type semiconductor and the film prepared at 250°C exhibits a mobility of 65.8 cm2/Vs with the resistivity of 7.543 × 103Ω cm. [ABSTRACT FROM PUBLISHER]