Department Of Physics

Permanent URI for this communityhttps://kr.cup.edu.in/handle/32116/57

Browse

Author: search.filters.author.Kumar, VijayHas files: No

Search Results

Now showing 1 - 7 of 7
  • No Thumbnail Available
    Item
    Mesoporous carbon/titanium dioxide composite as an electrode for symmetric/asymmetric solid?state supercapacitors
    (Elsevier Ltd, 2022-08-27T00:00:00) Arya, Anil; Iqbal, Muzahir; Tanwar, Shweta; Sharma, Annu; Sharma, A.L.; Kumar, Vijay
    This paper reports the successful synthesis of mesoporous carbon/titanium dioxide (MC/TiO2) composite electrodes via the hydrothermal method for supercapacitor (SC) applications. The morphology and structural properties of MC/TiO2 composites were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectra (FTIR). The electrochemical properties were recorded by cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) with an electrolyte (6 M KOH) in symmetric/asymmetric configuration. The specific capacitance (Cs) evaluated by CV is about 280F/g for composite electrode (95 % capacitance retention after 1000 cycles) and pristine has 150F/g @ 10 mV/s. Enhancement in capacitance is owing to faster charge dynamics within electrode material. The fabricated asymmetric device demonstrates high energy density (30.31 Wh/kg), than the symmetric configuration (?27 Wh/kg). Finally, both symmetric/asymmetric supercapacitors have illuminated a red LED, and strengthens the candidature of composite electrode for energy storage technology. � 2022 Elsevier B.V.
  • No Thumbnail Available
    Item
    High efficient carbon coated TiO2electrode for ultra-capacitor applications
    (IOP Publishing Ltd, 2021-10-08T00:00:00) Tanwar, Shweta; Arya, Anil; Singh, Nirbhay; Yadav, Bal Chandra; Kumar, Vijay; Rai, Atma; Sharma, A.L.
    The present paper reports the investigation of structural, optical, chemical bonding, and electrical properties of the carbon black (CB)/TiO2 composite synthesized via the standard sol-gel method. The structural and morphological properties have been investigated using x-ray diffraction and also field emission scanning electron microscopy to confirm the formation of the nanocomposite. The electrochemical performance of the two-electrode symmetric fabricated supercapacitor (SC) has been examined by complex impedance spectroscopy, cyclic voltammetry, and galvanostatic charge-discharge (GCD). The electrode CT15 (15% TiO2 in CB matrix) shows a high specific capacitance of 236 F g-1 at scan rate 10 mV s-1. The GCD illustrates good specific capacitance retention of 90.3% after 10 000 cycles and with energy density and power density values as 22 Wh kg-1 and 625 kW kg-1 respectively (at 1 A g-1) in the voltage window of 1.2 V. The CT15 electrode cell demonstrates superior electrochemical performance as compared to other electrodes. Electrochemical impedance spectroscopy (EIS) demonstrates the capacitive behaviour of the composite electrode with a low value of resistance. The SC cell having optimum performance has been chosen to demonstrate the glowing red light emitting diode. A mechanism has also been proposed based on received data parameters to validate the SC performance. � 2021 IOP Publishing Ltd.
  • No Thumbnail Available
    Item
    Fundamentals of Batteries and Supercapacitors: An Overview
    (CRC Press, 2021-09-06T00:00:00) Arya, Anil; Gaur, Anurag; Sharma, A.L.; Kumar, Vijay
    Energy plays an important role in daily human life and is the basic need in the present scenario. Nowadays, the development of energy sources is linked with the development of human civilization. The high energy density and high power density energy devices are on the radar of the research community. Batteries and supercapacitors (SCs) are two potential energy storage devices dominating the energy sector all over the world. This chapter starts with a focus on energy technologies and storage needs. Then, fundamentals of electrochemistry have been discussed followed by the working principle of battery and SC, and how energy is stored. Different types of batteries and SCs are discussed with their charge storage mechanisms. At last, important performance parameter and their influence on the overall device and its performance is presented. � 2022 Taylor & Francis Group, LLC.
  • No Thumbnail Available
    Item
    Nanostructured Li2MSiO4 (M=Fe, Mn) Cathode Material for Li-ion Batteries
    (CRC Press, 2021-09-02T00:00:00) Sharma, A.L.; Tanwar, Shweta; Singh, Nirbhay; Kumar, Vijay; Arya, Anil
    Li-ion batteries have emerged as a highly efficient energy storage device due to its high energy density, low cost, cyclic stability, and have dominated the markets all over the world. The battery comprises of cathode, anode, and electrolyte. The cathode material is crucial as it affects the overall cell performance and is an area of research globally. The suitable anode material is graphite and the electrolyte is gel/solid electrolyte (LiPF6). Recently, orthosilicates (Li2MSiO4; M= Fe, Mn, etc) based cathode material emerged as an alternative of LiCoO2 and LiFePO4 cathodes. The inherent structural stability in silicates is attributed to low cost, presence of Si-O covalent bonding in structure, and availability of two Li+ for transportation. The presence of two Li results in high energy density. So, to further enhance the energy density, researchers have adopted a doping, surface modification approach. Keeping the advantages of orthosilicates based electrode in mind, this chapter explores the fundamentals of battery, followed by characteristics of cathode material and strategy to tune the performance of orthosilicates based electrode. The complete methodology in terms of synthesis and characterization of the orthosilicates electrode has been explained. Finally, an important advancement in the orthosilicates based electrode material in battery performance is summarized followed by future aspects. � 2022 Taylor & Francis Group, LLC.
  • No Thumbnail Available
    Item
    Nanostructured Metal Oxides for Hybrid Supercapacitors
    (CRC Press, 2021-09-02T00:00:00) Arya, Anil; Gaur, Anurag; Kumar, Vijay; Tanwar, Shweta; Sharma, A.L.
    The present chapter highlights the fundamentals of supercapacitors (SCs), their classification with the main emphasis on the fabrication of hybrid SC using nanostructured transition metal oxide (TMO) based electrodes. The TMO based electrodes have grabbed the attention of researchers to point out a significant role in the enhancement of the SC device performance such as fast charging-discharging, energy density, power density, and cyclic stability. The tuning of valence charge and dominance of pseudocapacitive behavior is the key to achieve the superior performance of supercapacitors. In this article, we have focused on the hybrid approach to configuring the SC device and obtained enhanced electrochemical performance as compared to symmetric/non-hybrid supercapacitor. Consequently, this chapter provides insights about hybrid supercapacitors along with strategies to enhance cell performance. Furthermore, a glimpse of different TM based electrode material for the Hybrid SC device is also reported. � 2022 Taylor & Francis Group, LLC.
  • No Thumbnail Available
    Item
    Electrolytes for Li-Ion Batteries and Supercapacitors
    (CRC Press, 2021-09-06T00:00:00) Arya, Anil; Pandey, Lokesh; Gaur, Anurag; Kumar, Vijay; Sharma, A.L.
    This chapter is dedicated to the electrolyte that is a crucial component of any device. Electrolyte plays a dual role in the device, acts as a carpet for electrolyte ions, and also separates the electrodes to avoid short-circuiting or explosion. Initially, the characteristics parameter and selection criteria for the electrolyte will be discussed. Then, the organic electrolytes have been discussed followed by a focus on emerging novel gel/solid polymer electrolytes for application in battery and supercapacitor. The performance of the battery and supercapacitor is shown for different electrolytes. � 2022 Taylor & Francis Group, LLC.
  • No Thumbnail Available
    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.