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Poly(vinylidene fluoride) (PVDF), Barium Titanate (BaTiO3) and Montmorillonite (MMT) nanoclay based polymer nanocomposite (PNCs) were synthesized using a solution casting technique by encapsulating various loadings of BaTiO3 and MMT in PVDF matrix. The completely dispersed and highly flexible PVDF/BaTiO3/MMT nanocomposite films which were subjected to different characterization studies. The structural and morphological analysis of the synthesized nanocomposite films has been done using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD). BaTiO3 and MMT reinforcement in the polymer matrix results in structural modifications of the PNCs. Thermogravimetric analysis (TGA) were employed to assess the thermal characteristics of PVDF/BaTiO3/MMT PNCs. The dielectric properties such as dielectric constant (ϵ), dielectric loss (tan δ), and AC conductivity (σac) of nanocomposite films were also examined as functions of frequency (50 Hz to 10 MHz) and temperature (30 °C to 150 °C). The highest ϵ was obtained at low frequency at higher temperatures for all the nanocomposite films. These findings imply that the PVDF/BaTiO3/MMT nanocomposites can be an effective material for energy storage applications. [ABSTRACT FROM AUTHOR]

The present work centered attention on novel ionic liquid (IL) based on dicationic benzimidazolium ion containing amide group (DBimIL) synthesized using dialkylation of N-ethyl benzimidazole to followed with anion exchange reaction. To explore the potential application of ILs, there is a great need to grasp their structural and physical properties. We have developed three different set of DBimIL based ionic liquids with chloride, hexafluorophosphate and perchlorate anions in aqueous media, respectively. Their structural features were studied using 1H, 13C-NMR, FTIR, and HRMS spectroscopy, respectively. The temperature-dependent dielectric characteristics of ILs were closely examined angular frequency in the range of 0.6–125 rad/s from 30 to 150 °C. The relationship between the structural and dielectric properties of ILs established. The dielectric parameters like dielectric constant, dissipation factor and the real part of ac conductivity were found to be affected significantly with the tuning of anionic moieties of ionic liquids. The ability of materials to store a charge in electromagnetic field was measured. From dielectric and electrical studies, to bring to an end, especially in particular way that the present IL systems have an enormous potential for the designing of modern-day energy storage devices. [ABSTRACT FROM AUTHOR]

A green synthesis approach has been adopted to prepare nickel sulphide nanoparticles (NiS NPs) using banana peel extract (BPE) as a reducing and capping agent. Polyvinyl alcohol (PVA)/NiS nanocomposite films were fabricated using a cost-effective solution casting technique by dispersing different contents of NiS NPs (0–3 wt%) in the PVA matrix. Various characterization techniques were employed to analyze the structural, thermal and morphological properties of the PVA / NiS nanocomposite films. Further, the dielectric behaviour of these nanocomposite films was investigated at frequency range 50 Hz–20 MHz and in the temperature range 40 °C–140 °C. Also, there exists a significant interaction between the polymer matrix and the nanofiller as evident from the notable improvement in the dielectric properties of the nanocomposites. The dielectric constant ( ε ) value of PVA/NiS nanocomposite film with 3 wt % NiS NPs loading was found to be 154.55 at 50 Hz and at 140 °C which is 22 times greater than the dielectric constant value of neat PVA (6.90). These results suggest that NiS NPs were dispersed homogeneously in the PVA matrix.

In the present study, graphene oxide (GO)-reinforced poly (4-styrenesulfonic acid) (PSSA)/polyvinyl alcohol (PVA) blend composite films were prepared using colloidal blending technique at various concentrations of GO (0-3wt.%). The morphological investigations of the prepared composites were carried out using polarized optical microscopy and scanning electron microscopy. The electrical properties of composites were evaluated using an impedance analyzer in the frequency range 50Hz to 20MHz and temperature in the range 40-150C. Morphological studies infer that GO was homogeneously dispersed in the PSSA/PVA blend matrix. Investigations of electrical property indicate that the incorporation of GO into PSSA/PVA blend matrix resulted in the enhancement of the impedance ( and the quality factor (-factor) values. A maximum impedance of about 4.3210 was observed at 50Hz and 90C for PSSA/PVA/GO composites with 3wt.% GO loading. The -factor also increased from 8.37 for PSSA/PVA blend to 59.8 for PSSA/PVA/GO composites with 3wt.% GO loading. These results indicate that PSSA/PVA/GO composites can be used for high- capacitor applications. [ABSTRACT FROM AUTHOR]

PVDF-HFP/BaTiO 3 /GQDs polymer nanocomposite films with good flexibility and high dielectric constant (ϵ) at low frequency were prepared via solution casting technique. Different compositions of BaTiO 3 (non-conducting ceramic nanofiller) and Graphene quantum dots (GQDs) (conducting nanofiller) utilized as co-filler were embedded in poly (vinylidene fluoride-co-hexafluoroethylene) (PVDF-HFP) polymer matrix. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and Scanning electron microscopy (SEM) techniques were employed to characterize the prepared nanocomposite films. The mechanical properties of PVDF-HFP/BaTiO 3 /GQDs nanocomposite films were also investigated. Dielectric properties of nanocomposite films such as dielectric constant (ϵ), dielectric loss (tanδ) and AC conductivity ( σ ac ) were also determined as a function of frequency and temperature. Highest ϵ with relatively low tanδ obtained at low frequency for maximum temperature in all polymer nanocomposite films. The σ ac increases from lower (100 Hz) to higher frequency up to 100 kHz and drops to zero for the further increment of frequency. These results suggest that the PVDF-HFP/BaTiO 3 /GQDs nanocomposites are the most promising materials for energy storage applications., (Copyright © 2021 Elsevier Inc. All rights reserved.)

In the present work, the cost effective and facile hydrothermal synthesis technique was adopted to synthesize the copper (׀׀) oxide (CuO)-Nanoparticles (NPs). Physico-chemical characterization of the synthesized CuO-NPs was done by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Ultraviolet-visible spectroscopy (UV-Vis), and scanning electron microscopy (SEM) analysis were carried out to study the structural, optical, and surface morphology of nanomaterial. XRD analysis revealed that the synthesized CuO-NPs had monoclinic structure and the average crystallite size is 20 nm. FTIR spectra indicate the vibrational bands of metal oxygen bonds (Cu-O). UV-visible absorption spectra were utilized to determine the energy band gap (E g ) of the CuO-NPs. In addition, we fabricated the chemiresistive sensor using synthesized CuO-NPs for detecting Volatile Organic Compounds (VOCs). These results demonstrate that CuO-NPs based chemiresistive sensor is ideal for qualitative detection of BTEX chemicals vapors (i.e. Benzene, Toluene, Ethylbenzene, and Xylene)., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Modifying the structures and doping are proven to be effective methods to tune the structural and electrical properties of g-C 3 N 4 quantum dots. Hence, in this study, tri-s-triazine and tri-nitro tri-s-triazine have been studied by functionalizing their edges with hydrogen. The H-functionalized tri-nitro tri-s-triazine quantum dot displays a buckled structure with a band gap of 1.988 eV, whereas the tri-s-triazine demonstrates a planner structure with a band gap of 1.636 eV. The obtained results have been compared with the previous results. The absorbance spectrum of H-functionalized trinitro tri-s-triazine falls under the visible region with a peak value of 488 nm, and the absorption spectrum of tri-s-triazine falls at 790 nm. The planarity of the tri-nitro tri-s-triazine structure is improved by doping the B atom in the N site, and the band gap of H-functionalized B doped tri-nitro tri-s-triazine is 1.143 eV. The absorbance spectrum of H-functionalized B doped tri-nitro tri-s-triazine is 508 nm. The reactivity of the structure is increased by doping B atoms, and it is confirmed by the electrophilicity index. Similarly, the H-functionalized B doped tri-s-triazine exhibits a band gap of 1.328 eV. Further, the tri-s-triazine structures are arranged in ternary form, and the properties are studied by increasing the number of B atoms in the tri-s-triazine rings. The outcome presents that the structures are planar, and band gap values are reduced further. Also, the reactivity of the sheets is increased, which is confirmed by the electrophilicity index. It is proposed that the sheets with a high reactivity can be used for the removal of hazardous ions and molecules from the industrial wastage., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)