ORCID Profile
0000-0002-4003-0058
Current Organisation
VIT University Department of Physics
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Publisher: Elsevier BV
Date: 12-2016
Publisher: Wiley
Date: 21-08-2021
Abstract: Mesoporous carbon nitrides with C 3 N 5 and C 3 N 6 stoichiometries created a new momentum in the field of organic metal‐free semiconductors owing to their unique band structures and high basicity. Here, we report on the preparation of a novel graphitic microporous carbon nitride with a tetrazine based chemical structure and the composition of C 3 N 5.4 using ultra‐stable Y zeolite as the template and aminoguanidine hydrochloride, a high nitrogen‐containing molecule, as the CN precursor. Spectroscopic characterization and density functional theory calculations reveal that the prepared material exhibits a new molecular structure, which comprises two tetrazines and one triazine rings in the unit cell and is thermodynamically stable. The resultant carbon nitride shows an outstanding surface area of 130.4 m 2 g −1 and demonstrates excellent CO 2 adsorption per unit surface area of 47.54 μmol m −2 , which is due to the existence of abundant free NH 2 groups, basic sites and microporosity. The material also exhibits highly selective sensing over water molecules (151.1 mmol g −1 ) and aliphatic hydrocarbons due to its unique microporous structure with a high amount of hydrophilic nitrogen moieties and recognizing ability towards small molecules.
Publisher: Elsevier BV
Date: 12-2018
Publisher: Elsevier BV
Date: 05-2018
Publisher: Wiley
Date: 19-08-2021
Abstract: Designing a metal‐free and highly efficient electrocatalyst with large number of active sites and high stability for oxygen reduction reaction (ORR) holds great promise for the commercial production of low‐cost and stable fuel cells. Herein, a novel strategy of introducing both porosity and electrochemically active carbon nitride (CN) matrix in the graphene nanoplatelets (GNPs) through a simple integration of chemical activation and the polymerization of CN precursor is reported. The characterization results confirm the successful integration of the CN matrix and the formation of the porous network in the GNPs. The highly dispersed CN matrix in the GNPs offers not only a large number of electrochemically active sites but also enhances the interaction with the oxygen intermediates, while the GNPs significantly reduce the electron localization in the catalyst. Due to the combined effect of CN matrix, porosity, and the conductive graphene framework, the prepared electrocatalyst gives exceptional ORR activity with a current density of 5.1 mA cm −2 and a positive onset potential of 0.87 V, which also shows excellent stability and tolerance toward methanol. The strategy adopted here may open a platform to design a series of novel electrocatalysts with enhanced performance for ORR in fuel cells.
Publisher: The Chemical Society of Japan
Date: 15-02-2021
Publisher: Elsevier BV
Date: 03-2016
Publisher: Wiley
Date: 25-11-2018
Abstract: Mesoporous carbon nitrides (MCN) with C 3 N 4 stoichiometry could find applications in fields ranging from catalysis, sensing, and adsorption–separation to biotechnology. The extension of the synthesis of MCN with different nitrogen contents and chemical structures promises access to a wider range of applications. Herein we prepare mesoporous C 3 N 5 with a combined triazole and triazine framework via a simple self‐assembly of 5‐amino‐1 H ‐tetrazole (5‐ATTZ). We are able to hybridize these nanostructures with graphene by using graphene–mesoporous‐silica hybrids as a template to tune the electronic properties. DFT calculations and spectroscopic analyses clearly demonstrate that the C 3 N 5 consists of 1 triazole and 2 triazine moieties. The triazole‐based mesoporous C 3 N 5 and its graphene hybrids are found to be highly active for oxygen reduction reaction (ORR) with a higher diffusion‐limiting current density and a decreased overpotential than those of bulk g‐C 3 N 4 .
Publisher: AIP Publishing LLC
Date: 2014
DOI: 10.1063/1.4873108
Publisher: Elsevier BV
Date: 2016
DOI: 10.1016/J.EJPS.2015.11.018
Abstract: Conformational and molecular docking analysis of 2-acetylamino-5-bromo-6-methylpyridine molecule was carried out and the vibrational spectral analysis was also carried out using experimental and theoretical methods. The calculated and experimentally observed vibrational frequencies of the molecule were assigned and compared. The pyridine ring CH stretching and CH3 stretching vibrational modes were shifted towards higher wavenumber (blue shift). The C=O stretching vibrational frequency was shifted towards lower wavenumber (red shift). Ultraviolet-visible spectrum of the molecule simulated theoretically was further validated experimentally. Molecular reactivity and stability were investigated using the frontier molecular orbital analysis and the related quantum chemical molecular properties. Natural bond orbital analysis and the structure activity relations were also studied to confirm the bioactivity of the molecule. Anticancer activity was examined based on molecular docking analysis and it has been identified that the AABMP molecule can act as a good inhibitor against lung cancer.
Publisher: American Chemical Society (ACS)
Date: 24-04-2022
Abstract: Vanadium dioxide (VO
Publisher: Elsevier BV
Date: 2022
Publisher: SAGE Publications
Date: 30-08-2020
Abstract: Singleness emerges as a theme in studies on contemporary relationships across societies, including in Indonesia. While in most Western societies, singleness reflects an in idual’s personal preference, marriage is viewed as cultural imperative in Indonesia, and being single is often held involuntarily by most never-married adults. This study outlines the reasons of why Indonesian in iduals remain involuntarily single. The interviews of 40 never-married adults aged 27–52 years ( M age = 33.14 SD = 4.04) revealed that gender and religious differences regarding marriage expectation are central themes in understanding involuntary singleness. The study particularly revealed four gender-specific reasons for why in iduals remained involuntarily single: obtaining a career, having an incompatible marriage expectation, having dependent family members, and having temporal perspectives of singleness. Two themes emerged regarding the religious perspective of singleness: religious interpretations about singleness and religion-related coping ways of being involuntarily single. The themes suggest that marriage is not a mere personal fulfillment as cultural and religious values determine in iduals’ marriage feasibility. While offering a new perspective of involuntary singleness from non-Western perspective, the results inform strategies to cope with unwanted singleness, particularly in the marriage- and religion-preoccupied societies.
Publisher: Wiley
Date: 20-01-2021
Publisher: Springer Science and Business Media LLC
Date: 07-09-2019
Publisher: Elsevier BV
Date: 04-2017
Publisher: Springer Science and Business Media LLC
Date: 08-09-2015
Publisher: Elsevier BV
Date: 04-2021
Publisher: Springer Science and Business Media LLC
Date: 09-05-2017
Publisher: Elsevier BV
Date: 06-2019
DOI: 10.1016/J.JCONREL.2019.05.015
Abstract: We recently developed a cell-penetrating drug carrier composed of albumin (HSA) combined with palmitoyl-cyclic-(D-Arg)
Publisher: Elsevier BV
Date: 12-2021
Publisher: Springer Science and Business Media LLC
Date: 04-01-2021
Publisher: Wiley
Date: 27-04-2023
Abstract: A simple strategy to fabricate Cu single atoms (SAs) layer‐intercalated MoS 2 only by stirring Cu metals with MoS 2 nanosheets solution at room temperature is reported. An ultra‐high concentration (Cu: Mo = 98 at%) of Cu SAs is achieved and the intercalated Cu atoms strongly enhance the stability of the thermodynamically unstable 1T‐phase dominant MoS 2 . Notably, the as‐synthesized MoS 2 /Cu‐SAs exhibit a surprisingly high proportion of the metallic phase (64%) even after annealing at 800 °C in 5% H 2 /Ar foaming gas, indicating extraordinary thermostability of the Cu intercalated 1 T‐MoS 2 . In addition to, the as‐prepared MoS 2 /SAs exhibit outstanding catalytic performance owing to the improved electrical conductivity and the highly active unsaturated Cu SAs. This strategy is confirmed as a universal method for producing SAs of other metals and other 2D nanosheets can also be used as the host for SAs intercalation other than MoS 2 . This study may provide an effective strategy to fabricate facile and low‐cost SAs catalysts.
Publisher: Elsevier BV
Date: 2022
DOI: 10.2139/SSRN.4115544
Publisher: Wiley
Date: 21-08-2021
Abstract: Mesoporous carbon nitrides with C 3 N 5 and C 3 N 6 stoichiometries created a new momentum in the field of organic metal‐free semiconductors owing to their unique band structures and high basicity. Here, we report on the preparation of a novel graphitic microporous carbon nitride with a tetrazine based chemical structure and the composition of C 3 N 5.4 using ultra‐stable Y zeolite as the template and aminoguanidine hydrochloride, a high nitrogen‐containing molecule, as the CN precursor. Spectroscopic characterization and density functional theory calculations reveal that the prepared material exhibits a new molecular structure, which comprises two tetrazines and one triazine rings in the unit cell and is thermodynamically stable. The resultant carbon nitride shows an outstanding surface area of 130.4 m 2 g −1 and demonstrates excellent CO 2 adsorption per unit surface area of 47.54 μmol m −2 , which is due to the existence of abundant free NH 2 groups, basic sites and microporosity. The material also exhibits highly selective sensing over water molecules (151.1 mmol g −1 ) and aliphatic hydrocarbons due to its unique microporous structure with a high amount of hydrophilic nitrogen moieties and recognizing ability towards small molecules.
Publisher: American Chemical Society (ACS)
Date: 02-07-2019
Abstract: Mesoporous carbon nitride (MCN) with well-ordered porous structures is a promising anode material for secondary ion batteries owing to their unique physico- and electrochemical properties. However, the practical application of these MCNs in sodium-ion batteries (SIBs) is still limited because of their confined interlayer distance, which results in restricted accommodation of Na ions inside the lattice. Here, we report on the synthesis of highly ordered sulfur-doped MCN (S-MCN) through a hard template approach by employing dithiooxamide (DTO) as a single molecular precursor containing carbon, nitrogen, and sulfur elements. The interlayer distance of carbon nitride is significantly expanded upon the introduction of larger S ions on the MCN lattice, which enables high capability of Na ion accommodation. We also demonstrate through the first-principles density functional theory calculation that the present S-MCN is highly optimized not only for the chemical structure but also for uptaking abundant Na ions with high adsorption energy. The specific discharge capacity of SIBs appears to be remarkably enhanced for S-MCN (304.2 mA h g
Publisher: American Chemical Society (ACS)
Date: 09-04-2020
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 04-2019
Publisher: Springer Science and Business Media LLC
Date: 25-03-2019
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C9NR02733E
Abstract: The effect of Cs substitution in MA 1−x Cs x PbBr 3 perovskites was explored using Raman spectroscopy and XRD to identify the microstructural evolution.
Publisher: Wiley
Date: 26-11-2018
Abstract: Mesoporous carbon nitrides (MCN) with C 3 N 4 stoichiometry could find applications in fields ranging from catalysis, sensing, and adsorption–separation to biotechnology. The extension of the synthesis of MCN with different nitrogen contents and chemical structures promises access to a wider range of applications. Herein we prepare mesoporous C 3 N 5 with a combined triazole and triazine framework via a simple self‐assembly of 5‐amino‐1 H ‐tetrazole (5‐ATTZ). We are able to hybridize these nanostructures with graphene by using graphene–mesoporous‐silica hybrids as a template to tune the electronic properties. DFT calculations and spectroscopic analyses clearly demonstrate that the C 3 N 5 consists of 1 triazole and 2 triazine moieties. The triazole‐based mesoporous C 3 N 5 and its graphene hybrids are found to be highly active for oxygen reduction reaction (ORR) with a higher diffusion‐limiting current density and a decreased overpotential than those of bulk g‐C 3 N 4 .
Publisher: Wiley
Date: 29-11-2020
Abstract: Carbon nitrides with a high N/C atomic ratio (>2) are expected to offer superior basicity and unique electronic properties. However, the synthesis of these nanostructures is highly challenging since many parts of the CN frameworks in the carbon nitride should be replaced with thermodynamically less stable NN frameworks as the nitrogen content increases. Thermodynamically stable C
Publisher: Wiley
Date: 03-2020
Publisher: American Chemical Society (ACS)
Date: 14-10-2022
Publisher: Elsevier BV
Date: 03-2015
DOI: 10.1016/J.SAA.2014.11.029
Abstract: The vibrational spectra of 2-amino-7-bromo-5-oxo-[1]benzopyrano [2,3-b]pyridine-3 carbonitrile were recorded using fourier transform-infrared and fourier transform-Raman spectrometer. The optimized structural parameters, vibrational frequencies, Mulliken atomic charge distribution, frontier molecular orbitals, thermodynamic properties, temperature dependence of thermodynamic parameters, first order hyperpolarizability and natural bond orbital calculations of the molecule were performed using the Gaussian 09 program. The vibrational frequencies were assigned on the basis of potential energy distribution calculation using the VEDA 4.0 program. The calculated first order hyperpolarizability of ABOBPC molecule was obtained as 6.908×10(-30) issue, which was 10.5 times greater than urea. The nonlinear optical activity of the molecule was also confirmed by the frontier molecular orbitals and natural bond orbital analysis. The frontier molecular orbitals analysis shows that the lower energy gap of the molecule, which leads to the higher value of first order hyperpolarizability. The natural bond orbital analysis indicates that the nonlinear optical activity of the molecule arises due to the π→π(∗) transitions. The Mulliken atomic charge distribution confirms the presence of intramolecular charge transfer within the molecule. The reactive site of the molecule was predicted from the molecular electrostatic potential contour map. The values of thermo dynamic parameters were increasing with increasing temperature.
Publisher: Springer Science and Business Media LLC
Date: 10-08-2019
Publisher: Springer Science and Business Media LLC
Date: 30-05-2020
Publisher: Springer Science and Business Media LLC
Date: 02-11-2022
Publisher: Wiley
Date: 05-04-2022
Abstract: Porous boron carbon nitride (BCN) is one of the exciting systems with unique electrochemical and adsorption properties. However, the synthesis of low‐cost and porous BCN with tunable porosity is challenging, limiting its full potential in a variety of applications. Herein, the preparation of well‐defined mesoporous boron carbon nitride (MBCN) with high specific surface area, tunable pores, and nitrogen contents is demonstrated through a simple integration of chemical polymerization of readily available sucrose and borane ammonia complex (BAC) through the nano‐hard‐templating approach. The bimodal pores are introduced in MBCN by controlling the self‐organization of BAC and sucrose molecules within the nanochannels of the template. It is found that the optimized s le shows a high specific capacitance (296 F g −1 at 0.5 A g −1 ), large specific capacity for sodium‐ion battery (349 mAg h −1 at 50 mAh g −1 ), and excellent CO 2 adsorption capacity (27.14 mmol g −1 at 30 bar). Density functional theory calculations demonstrate that different adsorption sites (BC, BN, CN, and CC) and the large specific surface area strongly support the high adsorption capacity. This finding offers an innovative breakthrough in the design and development of MBCN nanostructures for energy storage and carbon capture applications.
Publisher: Informa UK Limited
Date: 05-11-2016
Publisher: Elsevier BV
Date: 04-2021
Publisher: American Chemical Society (ACS)
Date: 28-04-2020
Publisher: Elsevier BV
Date: 07-2016
Publisher: Elsevier BV
Date: 08-2014
DOI: 10.1016/J.SAA.2014.02.147
Abstract: The molecular structure of 2-(tert-butoxycarbonyl (Boc) -amino)-5-bromopyridine (BABP) was optimized by the DFT/B3LYP method with 6-311G (d,p), 6-311++G (d,p) and cc-pVTZ basis sets using the Gaussian 09 program. The most stable optimized structure of the molecule was predicted by the DFT/B3LYP method with cc-pVTZ basis set. The vibrational frequencies, Mulliken atomic charge distribution, frontier molecular orbitals and thermodynamical parameters were calculated. These calculations were done at the ground state energy level of BABP without applying any constraint on the potential energy surface. The vibrational spectra were experimentally recorded using Fourier Transform-Infrared (FT-IR) and micro-Raman spectrometer. The computed vibrational frequencies were scaled by scale factors to yield a good agreement with observed experimental vibrational frequencies. The complete theoretically calculated and experimentally observed vibrational frequencies were assigned on the basis of Potential Energy Distribution (PED) calculation using the VEDA 4.0 program. The vibrational modes assignments were performed by using the animation option of GaussView 05 graphical interface for Gaussian program. The Mulliken atomic charge distribution was calculated for BABP molecule. The molecular reactivity and stability of BABP were also studied by frontier molecular orbitals (FMOs) analysis.
No related grants have been discovered for Premkumar Selvarajan.