Journal Articles
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Item Computational materials discovery and development for Li and non-Li advanced battery chemistries(International Association of Physical Chemists, 2023) Sharma, H.; Nazir, A.; Kasbe, A.; Kekarjawlekar, P.; Chatterjee, K.; Motevalian, S.; Claus, A.; Prakash, V.; Acharya, S.; Sahu, K.K.Since the discovery of batteries in the 1800s, their fascinating physical and chemical properties have led to much research on their synthesis and manufacturing. Though lithium-ion batteries have been crucial for civilization, they can still not meet all the growing demands for energy storage because of the geographical distribution of lithium resources and the intrinsic limitations in the cell energy density, performance, and reliability issues. As a result, non-Li-ion batteries are becoming increasingly popular alternatives. Designing novel materials with desired properties is crucial for a quicker transition to the green energy ecosystem. Na, K, Mg, Zn, Al ion, etc. batteries are considered the most alluring and promising. This article covers all these Li, non-Li, and metal-air cell chemistries. Recently, computational screening has proven to be an effective tool to accelerate the discovery of active materials for all these cell types. First-principles methods such as density functional theory, molecular dynamics, and Monte Carlo simulations have become established techniques for the preliminary, theoretical analysis of battery systems. These computational methods generate a wealth of data that might be immensely useful in the training and validating of artificial intelligence and machine learning techniques to reduce the time and capital expenditure needed for discovering advanced materials and final product development. This review aims to summarize the application of these techniques and the recent developments in computational methods to discover and develop advanced battery chemistries. © 2023 by the authors; licensee IAPC, Zagreb, Croatia.Item An overview of the density functional theory on antioxidant bioactivity predictive feasibilities: Insights from natural antioxidant products(Elsevier B.V., 2024) Shaker, L.M.; A Al-Amiery, A.A.; Abed, T.K.; Khalid Al-Azzawi, W.K.; Kadhum, A.A.H.; Sulaiman, G.M.; Mohammed, H.A.; Khan, M.; Khan, R.A.Antioxidants play a crucial role in protecting biological systems from oxidative stress, which is implicated in a wide range of diseases. Computational methods have become increasingly valuable in studying the mechanisms of antioxidants, with density functional theory (DFT) being a popular approach. This review provides an overview of the theoretical basis of DFT and its application to molecular systems. It discusses the advantages and limitations of using DFT for studying antioxidants and explores the relationship between antioxidant activity and molecular structure. The paper also highlights the importance of solvation effects in determining antioxidant efficacy and suggests DFT-based methods for incorporating solvation effects into calculations. Case studies of specific antioxidants are presented to illustrate the role of the solvent environment in determining the antioxidant efficacy. Finally, it discusses the relationship between antioxidant activity and certain DFT parameters, and suggests future directions for research. Overall, this review provides valuable insights into the use of DFT in studying antioxidants, and sheds light on the future of computational studies in this field. © 2023Item New D-?-A type indole based chromogens for DSSC: Design, synthesis and performance studies(Elsevier Ltd, 2015) Babu, D.D.; Gachumale, S.R.; Anandan, S.; Vasudeva Adhikari, A.V.Three new Donor-?-Acceptor type dyes D1-3 carrying 3-(1-hexyl-1H-indol-3-yl)-2-(thiophen-2-yl)acrylonitrile as backbone with three different acceptor units were designed and synthesized as promising sensitizers for solar cell application. The new dyes were characterized using various spectral and elemental analyses. Their optical and electrochemical properties were investigated using spectrophotometry and cyclic voltammetry respectively, while their photovoltaic performance was evaluated by a device fabrication study. The devices were subjected to electrochemical impedance spectroscopy to gain an insight into the interfacial charge transfer and recombination process while in use. Further, density functional theory study was carried out to investigate their Frontier Molecular Orbital energy states. The study reveals that the dye carrying 4-aminobenzoic acid as an acceptor showed the highest photovoltaic efficiency among the three dyes. This can be attributed to the longer electron lifetime and lower recombination rates. Additionally, a Single crystal X-ray diffraction study confirmed the structure of a key intermediate. © 2014 Elsevier Ltd. All rights reserved.Item Spectral and DFT studies of anion bound organic receptors: Time dependent studies and logic gate applications(Beilstein-Institut Zur Forderung der Chemischen Wissenschaften info@beilstein-institut.de, 2017) Pangannaya, S.; Purayil, N.P.; Dabhi, S.; Mankad, V.; Jha, P.K.; Shinde, S.; Trivedi, D.R.New colorimetric receptors R1 and R2 with varied positional substitution of a cyano and nitro signaling unit having a hydroxy functionality as the hydrogen bond donor site have been designed, synthesized and characterized by FTIR, 1H NMR spectroscopy and mass spectrometry. The receptors R1 and R2 exhibit prominent visual response for F- and AcO- ions allowing the real time analysis of these ions in aqueous media. The formation of the receptor-anion complexes has been supported by UV-vis titration studies and confirmed through binding constant calculations. The anion binding process follows a first order rate equation and the calculated rate constants reveal a higher order of reactivity for AcO- ions. The 1H NMR titration and TDDFT studies provide full support of the binding mechanism. The Hg2+ and F- ion sensing property of receptor R1 has been utilized to arrive at "AND" and "INHIBIT" molecular logic gate applications. © 2017 Pangannaya et al.; licensee Beilstein-Institut.Item Efficient non-doped bluish-green organic light emitting devices based on N1 functionalized star-shaped phenanthroimidazole fluorophores(Elsevier B.V., 2018) Tagare, J.; Ulla, H.; Satyanarayan, M.N.; Sivakumar, S.In this paper, two star-shaped fluorescent phenanthroimidazole fluorophores, tris(4-(1-(3-(trifluoromethyl)phenyl)-1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)amine (PIMCFTPA) and tris(4-(1-(4-(trifluoromethyl)phenyl)-1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)amine (PIPCFTPA) with a D–?–A structure were designed and synthesized by attaching a hole-transporting triphenylamine and an electron transporting phenanthroimidazole moiety. A detailed photophysical, thermal, electrochemical and related properties were systematically studied. Furthermore, theoretical investigations (DFT) were performed to get a better understanding of the electronic structures. In particular, PIMCFTPA shows blue shifted emission due to the most twisted conformation and reduced intermolecular interaction as compared with PIPCFTPA. Both the fluorophores exhibit high glass transition temperatures and high thermal stabilities with decomposition temperatures up to 377 °C. The excellent stability renders them promising materials in electroluminescent devices. Non-doped organic light-emitting devices (OLEDs) using these fluorophores as emissive materials display bluish green emissions with high efficiency (6.58 cdA?1, 5.91 lmW?1, 3.62% at 100 cdm?2), low turn-on voltages (2.83 V) (PIMCFTPA) and excellent spectral stability. Our results suggest that the molecular design strategy of integrating TPA with phenthroimdazole play an important role in the device performance. © 2017 Elsevier B.V.Item Multicoloured Thiophene Based AIEgens: Single Crystal Structure Elucidation, Spectral Behaviour and DFT Studies(Wiley-Blackwell info@wiley.com, 2018) Mohan, M.; Pangannaya, S.; Satyanarayan, M.N.; Trivedi, D.R.A series of Schiff base thiophene derivatives, D1 to D9, which exhibits a phenomenon of aggregation-induced emission enhancement (AIEE) have been synthesised and characterized by standard spectroscopic techniques. Multicoloured emission enhancement has been achieved just by introduction of electron donating and withdrawing substituent on the thiophene moiety. Few of the molecules in the series exhibited enhanced fluorescence emission intensity in solvent mixture in comparison with that observed in pure solvent supportive of AIE. Single crystal x-ray diffraction (SCXRD) studies on selected molecules, D6 and D7 of the series revealed the existence of planar structure and a herringbone type of crystal packing arrangement. In specific, molecules D6 and D7, possesses a larger ?-? stacking distance of around 4.866 Å and 4.636 Å, which curbs all the non-radiative pathways, in turn leading to AIEE. DFT and TDDFT calculations confirm the structural planarity supportive of SCXRD analysis and the nature of electronic transition correlating well with the experimental results. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, WeinheimItem New cyanopyridine based conjugative polymers as blue emitters: Synthesis, photophysical, theoretical and electroluminescence studies(Elsevier B.V., 2018) Pilicode, N.; K M, N.; M N, S.; Vasudeva Adhikari, A.V.Herein, we report the design of three new blue light emitting conjugated polymers (Th-Py-1, Th-Py-2 and Th-Py-3), carrying cyanopyridine ring as a strong electron accepting unit and thiophene as well as phenylene vinylene scaffolds with different substituents, as electron donating moieties. The newly designed monomers/polymers were synthesized using well-known synthetic protocols such as cyclocondensation, O-alkylation, Suzuki cross coupling, Wittig and Knoevenagel reactions. They were well-characterized by spectral, thermal, photophysical, electrochemical and gel permeation chromatography (GPC) techniques. Further, they were subjected to theoretical studies using DFT simulations, performed at B3LYP/TZVP level using Turbomole 7.2 V software package. The new polymers were tested in PLED devices (ITO/PEDOT: PSS/Polymer/Al) as emissive materials. Optical studies revealed that, all the polymers displayed light absorption in the range of 377–397 nm and blue light emission in the order of 432–482 nm, respectively. Further, their band-gaps were calculated to be in the order of 2.55–2.64 eV using both optical and electrochemical data. Furthermore, the TGA study indicated that, they possess good thermal stability with onset decomposition temperature, greater than 300 ?C under nitrogen atmosphere. Interestingly, use of these polymers in new PLEDs as emissive layers, has shown improved performance when compared to previously reported polymers in similar type of devices. They show blue light emission with a low threshold voltage of 3.5–3.9 V, affirming an efficient electron injection in the diodes. © 2018 Elsevier B.V.Item Simple thiophene based organic dyes as active photosensitizers for dssc application: From molecular design to structure property relationship(Sumy State University larysa.odnodvorets@gmail.com, 2020) Keremane, K.S.; Naik, P.; Vasudeva Adhikari, A.V.The main objective of our present investigation includes the design synthesis and characterization of two novel D--A configured thiophene based dyes C1-2, carrying two different anchors and the same donor system. In the new design, a simple O-alkylated phenyl group as a donor scaffold, cyanovinylene and thiophene group serve as a-spacer, while cyanoacetic acid, barbituric acid units function as electron acceptor/ anchoring units. The newly synthesized compounds were characterized by FTIR, NMR spectroscopic techniques including the elemental analysis. Further, their optical properties were investigated by using UV-visible, fluorescence spectrophotometer. In addition, the Density functional theory (DFT) calculations were performed to get their electron distribution in FMO levels. In order to investigate their photovoltaic characteristics, the synthesized dyes were employed as sensitizers towards the fabrication of DSSC's. The device fabricated with dye C1 displayed better PCE of 1.2 % with JSC of 3.64 mA·cm-2, VOC of 0.50 V and FF of 65 % than other dye C2. These experimental results provide a better understanding and deeper insight into the intricacies involved in the design of superior sensitizers to further improve the performance of DSSCs. © 2020 Sumy State University.Item Nicotinonitrile centered luminescent polymeric materials: Structural, optical, electrochemical, and theoretical investigations(John Wiley and Sons Inc, 2020) Pilicode, N.; Naik, P.; Vasudeva Adhikari, A.V.Herein, we describe the design, synthesis, and structural characterization of three new push-pull type conjugative polymers, that is, VPPy1-3 comprising strong electron-withdrawing N-heterocyclic nicotinonitrile scaffold coupled with electron-donating phenylene units through vinylene bridges, as promising candidates for optoelectronic applications. They were successfully synthesized from their respective co-monomers by simple polycondensation synthetic routes, viz. Knoevenagel and Wittig reactions. All the polymers were subjected to photophysical, electrochemical, thermal, and theoretical studies in order to ascertain their suitability in polymer light-emitting diode applications as blue emitters. Evidently, they are readily soluble in most of the organic solvents, enabling them easy solution-processable. These new polymers display strong blue photoluminescence at the peak in the range of 431 to 462 nm with a wide optical bandgap in the order of 2.55 to 2.63 eV. The obtained electrochemical data were employed to evaluate their HOMO/LUMOs. The density functional theory calculations generated useful information on their FMO, molecular geometries, and electronic properties. Also, the influence of their structural modification on the above-said properties was discussed in detail to reveal the structure-property relationship. Conclusively, these results illustrate the great prospective of this class of polymeric materials for the application in solution-processable blue LEDs. © 2020 Society of Plastics EngineersItem Phenanthroimidazole-based chromophores for organic light-emitting diodes: synthesis, photophysical, and theoretical study(John Wiley and Sons Ltd, 2020) Tagare, J.; Verma, N.; Tarafder, K.; Sivakumar, S.Organic light-emitting diodes (OLED) are gaining attention and making a significant contribution to the area of lighting and displays technology. The synthesis of new materials that can act as a host as well as emissive materials is crucial and efforts have been made in this direction in this research. Here, four star-shaped fluorophores, with a donor–acceptor (D–A) structure and with triphenylamine and phenanthroimidazole groups with different substitutions at the N1 position of the imidazole moiety, were designed and synthesized. Synthesized fluorophores showed sufficient thermal stability (10% Td in the range 230–280°C). Ultraviolet–visible (UV–vis) spectra of the fluorophores showed multiple absorption bands (bands in the UV region, due to ?–?* transitions of the conjugated aromatic portion) and all fluorophores showed blue emission in dichloromethane solution. Electrochemical analysis indicated that all fluorophores had excellent oxidation and reduction characteristics. Theoretical calculations were also performed to better understand the structural and electronic properties of the synthesized fluorophores. All fluorophores had higher triplet (T1) energy (ranging from 2.49–2.52 eV) than the widely used green (Ir(ppy)3 –2.4 eV) and red (Ir (piq)2 acac – 2.2 eV) dopant materials. These results indicated that these fluorophores would be useful as host materials for efficient green and red phosphorescent OLEDs. © 2020 John Wiley & Sons, Ltd.
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