Department Of Physics
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Item Effects of Interfacial Interactions and Nanoparticle Agglomeration on the Structural, Thermal, Optical, and Dielectric Properties of Polyethylene/Cr2O3 and Polyethylene/Cr2O3/CNTs Nanocomposites(Springer, 2022-11-22T00:00:00) Gupta, Jaya; Kumar, Ajay; Roy, Ayan; Anu; Deeksha; Kour, Pawanpreet; Singh, Ravi Pratap; Yogesh, Gaurav Kumar; Yadav, KamleshIn this report, we have synthesized the binary and ternary phase nanocomposites [(polyethylene (PE)1?X/(Cr2O3)x) and (PE)1?X/(Cr2O3)X/CNTs (where X = 0,�2%, 4%, 6%, 8%, and 10%)] using the melt mixing method and studied the structural, optical, thermal and dielectric properties with an increase in Cr2O3 nanofiller concentration. Our results show an increase in interfacial interactions between Cr2O3 nanofiller and PE matrix with an increase in nanofiller concentration up to X = 6%. After that, the interactions decreased with a further increase in X because of the increase in the size of the Cr2O3 nanoparticle aggregates. Incorporating 2% carbon nanotubes (CNTs) into (PE)1?X/(Cr2O3)X nanocomposites, further decreases the interactions between the Cr2O3 nanofiller and the PE matrix. � 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.Item Synergistically modified WS2@PANI binary nanocomposite-based all-solid-state symmetric supercapacitor with high energy density(Royal Society of Chemistry, 2022-03-09T00:00:00) Iqbal, Muzahir; Saykar, Nilesh G.; Alegaonkar, Prashant S.; Mahapatra, Santosh K.The rapid development of intelligent, wearable, compact electronic equipment has triggered the need for durable, flexible, and lightweight portable energy storage devices. Nanomaterials that are capable of delivering the high specific power density and commensurate energy density are potential candidate for realizing such devices. Herein, we report the facile synthesis of a binary nanocomposite WS2@PANI by utilizing hydrothermal and physical blending techniques to assess it as an electrode material for high-performance supercapacitors. The nanocomposite electrode delivered specific capacitance >335 F g?1 @ 10 mV s?1 (two-electrode), achieving energy and power densities of ?80 W h kg?1 and ?800 W kg?1, respectively, with capacitance retention of 83% even after 5000 charge-discharge cycles @ 10 A g?1, all of which are superior to the WS2 electrode. Dunns model quantifies capacitive and intercalative contributions that showed the cumulative effect of both to realize a robust, cost-effective, and energy-efficient device. The strategically incorporated PANI broadened the electrochemical window and the device's overall performance, resulting in high specific energy density. We demonstrated that our all-solid-state symmetric supercapacitor could be used to illuminate a light-emitting diode and drive a rotary motor. We believe that our WS2@PANI binary nanocomposite will be a potential candidate for energy storage devices. � 2022 The Royal Society of ChemistryItem Enhanced capacitive behaviour of graphene nanoplatelets embedded epoxy nanocomposite(Springer, 2021-01-06T00:00:00) Raval, Bhargav; Sahare, P.D.; Mahapatra, S.K.; Banerjee, I.For the development of advanced polymer nanocomposite processability, high-quality and cost-efficiency plays a crucial role which combines mechanical robustness with functional electrochemical properties. In this study, we fabricated the epoxy/graphene nanocomposite (EGNC) with different wt% ratio of graphene nanoplatelets (GNPs). The EGNCs were fabricated through a solution mixing process and used it as an electrode to enhance electrochemical properties. The GNPs and EGNCs characterized using XRD, Raman spectroscopy, ATR FT-IR, and FE-SEM for the structural conformation and surface morphological study. The electrochemical analysis results show significant improvement in the specific capacitance in the EGNC samples as compared to the blank epoxy film. Specific capacitance 17.74 Fg?1 was recorded at 10 mVs?1 scan rate in 1.0�M KOH electrolyte solution for the 1.0 wt% EGNC film by cyclic voltammetry analysis. The Galvanostatic charge�discharge and Ragone plots also show mended results by the addition of GNPs. � 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature.Item Nanofiller-assisted Na+-conducting polymer nanocomposite for ultracapacitor: structural, dielectric and electrochemical properties(Springer, 2021-01-04T00:00:00) Kamboj, Vashu; Arya, Anil; Tanwar, Shweta; Kumar, Vijay; Sharma, A.L.We report the preparation of ZrO2 nanofiller-incorporated polymer nanocomposite electrolyte based on the PEO-NaPF6 matrix via standard solution cast method. The structure and morphology of polymeric films have been examined with X-ray diffraction and field emission scanning electron microscopy. Different interactions between the polymer, salt and nanofiller have been examined by Fourier transform infrared technique. The temperature-dependent (40�100��C) electrical conductivity has been examined from complex impedance spectroscopy (CIS). The highest ionic conductivity is exhibited by 5�wt% nanofiller-based electrolyte and recorded ~ 2 � 10�4�S�cm?1 at 100��C. The voltage stability window of polymeric film checked from linear sweep voltammetry is about ~ 4�V, and ion transference number close to unity confirms the major contribution from ion conduction. The dielectric properties have been explored in terms of complex permittivity, loss tangent and complex conductivity. The dielectric plots have been further fitted with an associated equation to evaluate principal dielectric parameters. The optimized polymer electrolyte possesses the lowest relaxation time and the highest dielectric constant that suggests the highest ionic conductivity, which is in good correlation with impedance results. The dc conductivity is also highest for the optimum system, and relaxation time decreases with an increase in temperature. The thermal stability of polymer electrolytes is about 200��C, as examined by thermogravimetric analysis (TGA). The ion transport parameters n, ?, D have been evaluated via FTIR, impedance spectroscopy and Bandara and Mellander (B�M) approach. Finally, the optimized polymer nanocomposite film has been used as an electrolyte-cum-separator for the fabrication of a solid-state symmetric supercapacitor. The electrochemical parameters specific capacitance, energy density, power density have been examined from cyclic voltammetry and galvanostatic charge�discharge technique. It may be concluded that nanofiller incorporation is an effective strategy to enhance the properties of electrolyte and has the potential to adopt as an electrolyte-cum-separator for ultracapacitor. � 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature.Item Titania sensitized with SPADNS dye for dye sensitized solar cell(Springer New York LLC, 2016) Didwal, P.N.; Pawar, K.S.; Chikate, P.R.; Abhyankar, A.C.; Pathan, H.M.; Devan, R.S.Synthesis of anatase TiO2 nanoparticle with diameter about 25?nm is carried out by using chemical method and powder of TiO2 nanoparticle is pasted on fluorine doped tin oxide (FTO) coated glass by doctor blade. New organic SPADNS dye (C16H9N2Na3O11S3) is used first time to make the dye-sensitized solar cells (DSSC). Cell were constructed by using SPADNS dye loaded wide band gap anatase TiO2 nanoparticle on FTO coated glass as photo-anode, polyiodide as electrolyte, and platinum coated FTO as counter electrode. SPADNS dye was made from organic reagent which is low cost and easy available in market. Better adsorption of SPADNS dye on anatase TiO2 film is due to porous nature of TiO2. This better adsorption gives more transportation of electron from dye to TiO2 which increase the efficiency of solar cell. Although SPADNS dye is the first experiment with TiO2 nanoparticle for DSSC, it gives photocurrent (short-circuit current density) 1.04?mA/cm2, open-circuit voltage 0.59?V, with 0.9?% efficiency under 10?mW/m2 LED. ? 2016, Springer Science+Business Media New York.Item Structural, microstructural and electrochemical properties of dispersed-type polymer nanocomposite films(Institute of Physics Publishing, 2018) Arya, A.; Sharma, A.L.Free-standing solid polymer nanocomposite (PEO-PVC) + LiPF6-TiO2 films have been prepared through a standard solution-cast technique. The improvement in structural, microstructural and electrochemical properties has been observed on the dispersion of nanofiller in polymer salt complex. X-ray diffraction studies clearly reflect the formation of complex formation, as no corresponding salt peak appeared in the diffractograms. The Fourier transform infrared analysis suggested clear and convincing evidence of polymer-ion, ion-ion and polymer-ion-nanofiller interaction. The highest ionic conductivity of the prepared solid polymer electrolyte (SPE) films is ?5 10-5 S cm-1 for 7 wt.% TiO2. The linear sweep voltammetry provides the electrochemical stability window of the prepared SPE films, about ?3.5 V. The ion transference number has been estimated, t ion = 0.99 through the DC polarization technique. Dielectric spectroscopic studies were performed to understand the ion transport process in polymer electrolytes. All solid polymer electrolytes possess good thermal stability up to 300 ?C. Differential scanning calorimetry analysis confirms the decrease of the melting temperature and signal of glass transition temperature with the addition of nanofiller, which indicates the decrease of crystallinity of the polymer matrix. An absolute correlation between diffusion coefficient (D), ion mobility (?), number density (n), double-layer capacitance (C dl), glass transition temperature, melting temperature (T m), free ion area (%) and conductivity (?) has been observed. A convincing model to study the role of nanofiller in a polymer salt complex has been proposed, which supports the experimental findings. The prepared polymer electrolyte system with significant ionic conductivity, high ionic transference number, and good thermal and voltage stability could be suggested as a potential candidate as electrolyte cum separator for the fabrication of a rechargeable lithium-ion battery system. ? 2018 IOP Publishing Ltd.Item Optimization of salt concentration and explanation of two peak percolation in blend solid polymer nanocomposite films(Springer New York LLC, 2018) Arya, A.; Sharma, A.L.The present paper is focused toward the preparation of the flexible and free-standing blend solid polymer electrolyte films based on PEO-PVP complexed with NaPF6 by the solution cast technique. The structural/morphological features of the synthesized polymer nanocomposite films have been investigated in detail using X-ray diffraction, Fourier transform infra-red spectroscopy, Field emission scanning electron microscope, and Atomic force microscopy techniques. The film PEO-PVP + NaPF6 ((Formula presented.)8) exhibits highest ionic conductivity ~ 5.92 ? 10?6 S cm?1 at 40 ?C and ~ 2.46 ? 10?4 S cm?1 at 100 ?C. The temperature-dependent conductivity shows an Arrhenius type behavior and activation energy decreases with the addition of salt. The high temperature (100 ?C) conductivity monitoring is done for the optimized PEO-PVP + NaPF6 ((Formula presented.)8) highly conductive system and the conductivity is still maintained stable up to 160 h (approx. 7 days). The thermal transitions parameters were measured by the differential scanning calorimetry (DSC) measurements. The prepared polymer electrolyte film displays the smoother surface on addition of salt and a thermal stability up to 300 ?C. The ion transference number (tion) for the highest conducting sample is found to be 0.997 and evidence that the present system is ion dominating with negligible electron contribution. Both linear sweep voltammetry and cyclic voltammetry supports the use of prepared polymer electrolyte with long-term cycle stability and thermal stability for the solid-state sodium ion batteries. Finally, a two peak percolation mechanism has been proposed on the basis of experimental findings. [Figure not available: see fulltext.] ? 2018 Springer-Verlag GmbH Germany, part of Springer NatureItem Correlation of microscopic interaction with electrical conductivity in polymer separator of energy storage devices(Springer Science and Business Media, LLC, 2017) Sharma, Parul Kumar; Sharma, Anshul Kumar; Sadiq, M.; Sharma, A. L.In the present report solid polymer nanocomposite (PNCs) comprising of (PEO)14+ NaClO4+ wt% BaTiO3has been prepared by solution casting method. Important characterization like: FTIR (Fourier Transform Infrared Spectroscopy), and conductivity have been performed for the applicability of the prepared materials in device application. The highest conductivity of the prepared polymer nanocomposite materials has been estimated 1?10?4Scm?1for 15 wt% of BaTiO3. A very fine correlation has been built among polymer-ion, ion-ion and polymer ion interaction with obtained conductivity results. ? Springer International Publishing Switzerland 2017.Item Transport Properties of Solid Polymer Nanocomposite Films for Energy Device Applications(NIT Srinagar, 2016) Sadiq, M.; Sharma, A. L.Sample preparation of high quality new series polymer nanocomposite (PNC) films based on (PAN-PEO)-LiPF 6 +xwt. %DMMT has been prepared via solution cast technique. Keeping in view of applications of solid state PNC films, Fourier transform infrared (FTIR) spectroscopy is done for understanding of microscopic interaction among the different composite component present in the material system. The impedance and electrochemical analysis have been done to fulfill the objective of the materials for the energy storage/conversion device applications. Thermo gravimetric analysis (TGA) has been done to estimate the thermal stability of the prepared polymer nanocomposite films.