Faculty Publications

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Publications by NITK Faculty

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    Design of an HV capacitor using the inherent advantage of charge simulation method and experimentations
    (Institution of Engineering and Technology journals@theiet.org, 2018) Devarajan, H.; Punekar, G.S.; Kishore, N.K.
    Standard capacitors form an important component of the measurement and instrumentation in the electrical laboratory. A high-voltage (HV) standard capacitor of 100 pF, 12 kV (rms) is designed using the charge simulation method (CSM). CSM is a semi-analytical method and it provides inherent advantage in designing a capacitor from the first principle. The capacitance is obtained from the magnitude of the simulating charges of the CSM-based model and the corresponding potential. The design details of HV standard capacitor are discussed along with the analysis of the potential and the electric stress distribution. The electric stress everywhere in the capacitor, which is designed, is assured to be <5 kV/cm, which was set as the limiting (maximum permissible) stress. The capacitance of the fabricated unit is measured in the HV laboratory. The CSM-based result of the capacitance of the designed HV capacitor agree well with the results of the laboratory experimental measurement. The inherent advantage of CSM in designing a capacitor is confirmed by comparing with the results of method of moments (MoM). © The Institution of Engineering and Technology.
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    Enhancement of quantum capacitance by chemical modification of graphene supercapacitor electrodes: a study by first principles
    (Indian Academy of Sciences, 2019) Sruthi, T.; Tarafder, K.
    In this paper, we specify a powerful way to boost quantum capacitance of graphene-based electrode materials by density functional theory calculations. We performed functionalization of graphene to manifest high-quantum capacitance. A marked quantum capacitance of above 420?Fcm-2 has been observed. Our calculations show that quantum capacitance of graphene enhances with nitrogen concentration. We have also scrutinized effect on the increase of graphene quantum capacitance due to the variation of doping concentration, configuration change as well as co-doping with nitrogen and oxygen ad-atoms in pristine graphene sheets. A significant increase in quantum capacitance was theoretically detected in functionalized graphene, mainly because of the generation of new electronic states near the Dirac point and the shift of Fermi level caused by ad-atom adsorption. © 2019, Indian Academy of Sciences.
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    Vanadium doped CaTiO3cuboids: role of vanadium in improving the photocatalytic activity
    (Royal Society of Chemistry, 2021) Bantawal, H.; Shenoy, U.S.; Bhat, D.K.
    CaTiO3has attracted enormous interest in the fields of photocatalytic dye degradation and water splitting owing to its low cost, excellent physicochemical stability and structural tunability. Herein, we have developed a simple one pot solvothermal approach which directs V into the Ti sites in the isovalent state during the synthesis of V doped CaTiO3cuboids. The prediction of reduction in the band gap due to the formation of additional levels just beneath the conduction band edge by the first principles density functional electronic structure study is confirmed by the experimental results. The suppression of charge carrier recombination in 1.0 V leads to the highest photocatalytic activity in the degradation of methylene blue. The percentage degradation of 94.2 indicates its suitability as an excellent catalyst for photocatalytic water treatment. © The Royal Society of Chemistry 2021.