Conference Papers

Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/28506

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    Effect of pressure on the band structure of BC3
    (American Institute of Physics Inc. subs@aip.org, 2016) Manju, M.S.; Harikrishnan, H.; Ajith, A.; Valsakumar, M.C.
    Density functional theory (DFT) calculations were carried out to study the effect of pressure on the band structure of two dimensional BC3 sheet. BC3 is a semiconductor at ambient conditions having a band gap of ~0.3 eV. Electronic structure calculations are carried out on BC3 at pressures of 5, 20, 50 and 100 GPa. The system shows a semiconductor - metal transition by the application of pressure without any structural transition. © 2016 Author(s).
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    Synthesis, Characterization and Performance Studies of a New Metal-Free Organic Sensitizer for DSSC application
    (Elsevier Ltd, 2018) Naik, P.; Babu, D.D.; Su, R.; El-Shafei, A.; Vasudeva Adhikari, A.V.
    In this present work we report, design, synthesis and performance studies of a new metal-free organic dye (N, N'-PABA) based on N,N-dimethyl-4-vinyl aniline carrying 4-amino benzoic acid as acceptor, as sensitizers for sensitizing photoanode (TiO2). In the sensitizers, N,N-dimethylaniline ring acts as anelectron donorwhile para amino benzoic acid function as electron acceptor/anchoring units. It was synthesized via condensation reaction starting from simple 4-(N,N-dimethyl amino)benzaldehyde and their structures were confirmed using spectral techniques like FTIR, 1HNMR, 13CNMR, MS and elemental analysis. Further, it was subjected to electrochemical and optical characterization in order to evaluate their band gap and absorption/emission behavior. Further, DFT studies were performed using turbo mole V6.6 software package to evaluate their optimized geometry and FMO levels. Finally, DSSC devices were fabricated using this dye under simulated solar radiation AM1.5G and result revealed that it shows a conversion efficiency of 1%. © 2018 Elsevier Ltd.
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    Molecular Engineering of a New Organic Chromophore with D-Ï€-A Architecture for Dye-Sensitized Solar Cells
    (Elsevier Ltd, 2018) Naik, P.; Vasudeva Adhikari, A.V.
    Herein, we report design and synthesis of a new metal-free organic dye N1 derived from (Z)-3-(9-hexyl-9H-carbazol-3-yl)-2-(thiophen-2-yl) acrylonitrile scaffold. In this design, the electron rich carbazole unit is connected to rhodanine-3-acetic acid via cyano vinyl thiophene as π-spacer. Its molecular structure was confirmed by FTIR, NMR, Mass spectral and elemental analyses. The dye was subjected to optical and electrochemical studies in order to investigate their absorption/emission behaviour as well as HOMO/LUMO energies. The DFT studies were performed using Turbomole 7.1V software and the results indicated the existence of proper charge separation between its HOMO and LUMO energy levels. © 2018 Elsevier Ltd. All rights reserved.
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    Study of Electronic and Optical Properties of Bulk and Monolayer Vanadium Di-Sulfide for Energy Storage Devices
    (Institute of Electrical and Electronics Engineers Inc., 2023) Yadav, A.K.; Jasil, T.K.; Pandey, S.K.
    In this study, the WIEN2k code implementation of the density functional theory (DFT) approach was used to examine the structural, electronic, and optical characteristics of bulk and monolayer VS2 material. For both bulk and monolayer VS2 material, we calculated the various properties including density of states, band-structure, and dielectric functions using the generalised gradient approximation (GGA). This method gives better results for the structural parameters and shows that monolayer VS2 is more favorable for energy storage devices. Additionally, we report the growth of the bulk and monolayer VS2 crystals using a chemical vapor deposition system. It was also found the crystal growth of monolayer VS2 started at the growth temperature of 690 °C. Bulk VS2 crystal growth also performed in this study. Raman spectroscopy shows a peak intensity started at 385 cm-1 for monolayer VS2 growth crystal at 690 °C. These observations show monolayer VS2 material is more suitable for energy storage devices. © 2023 IEEE.
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    An Online technique for estimation of the C and ESR of DC link capacitor in a boost converter based on multiple harmonic injection
    (Institute of Electrical and Electronics Engineers Inc., 2023) Muhammad Ramees, M.K.P.; Waseem Ahmad, M.
    Aluminium Electrolytic capacitors (AEC) are widely used in DC-DC converters. Health of the capacitor can be monitored using the capacitance and equivalent series resistance (ESR) as the ageing will decrease the capacitance and increase the ESR. Hence the estimation of these parameters is essential for the diagnosis of AEC. So, in this paper a method for the estimation of the capacitance and ESR are proposed. This method is based on the injection of low frequency current harmonics into the converter by modifying the duty ratio. A group of harmonic currents are injected, and corresponding voltage and current ripples are obtained using DFT analysis which is used to calculate the impedance at each frequency. From these impedances the capacitance and ESR are estimated using Least Mean Square (LMS) algorithm. Detailed simulation is carried out using MATLAB/Simulink and results are included in this paper. © 2023 IEEE.