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Synthesis of Chitosan Stabilised Platinum Nanoparticles and their Characterization
A simplistic green synthesis route for the platinum nanoparticles has been successfully identified by using chloroplatinic acid hexahydrate (H2 PtCl6.6H2 O) as the metal precursor and sodium borohydride (NaBH4) as the reducing agent at room temperature. Chitosan was used in minute quantities as capping and stabilizing agent. The visual observation of a black coloured colloidal suspension, the characteristic XRD peaks and the absorption peak in the range of 200-300nm confirmed the production of Pt nanoparticles. The average crystallite size calculated using Debye-Scherrer equation is about 19 2 nm and a less intense absorption peak was found at 246nm and 281nm. The FTIR spectroscopy was used to confirm the capping with chitosan molecules. Zeta-potential calculation gave a surface charge of-23.8mV, and this high negative value, then validated the stability of the nanoparticle. The synthesis of platinum nanoparticles is very significant for their catalytic activity and biomedical applications in industrial as well as healthcare sector. 2023, Books and Journals Private Ltd.. All rights reserved. -
Synthesis of Carbon Containing Composites for Energy and Environmental Applications
The population has grown rapidly, resulting in increased energy consumption and environmental issues. Researchers are developing new materials with unique physical and chemical properties to tackle these challenges. This has led to a focus on exploring novel approaches to synthesize micro and nanomaterials for use in the energy and environmental sectors. In this study, carbon-containing catalysts were developed as photocatalysts, electrocatalysts for water splitting reactions, and electrode materials for supercapacitor application. To evaluate the physicochemical characteristics of these materials, various characterization methods were employed, including X-ray diffraction, newlineScanning Electron Microscopy, Energy Dispersive X-ray Spectrometry, X-Ray Photoelectron Spectroscopy, High-resolution Transmission electron microscopy, Fourier Transform Infrared Spectroscopy, Differential reflectance spectroscopy, Dynamic light scattering, and Thermogravimetric analysis. The electrochemical and photocatalytic studies of the prepared materials were carried out by optimizing the different parameters. The four chapters include newlineCr2AlC MAX Phase as the catalyst used for photocatalysis, bismuth ferrite/Cr2CTx MXene, cobalt ferrite/Cr2CTx MXene composites for supercapacitor and electrocatalytic water splitting, bismuth ferrite/graphitic carbon nitride/N-doped graphene quantum dots for supercapacitor application, and Cobalt ferrite/graphitic carbon nitride/N-doped graphene quantum dots for supercapacitor and newlineelectrocatalytic water splitting application. -
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Synthesis of bismuth silicate nanostructures with tunable morphology and enhanced photocatalytic activity
Bismuth oxide due to its narrow bandgap has attracted significant attention as a photocatalyst. A facile and efficient method to synthesize bismuth silicate with tunable morphology and property is achieved in this study. Bismuth oxide and bismuth silicate have been synthesized by surfactant-assisted modified sol-gel method. The fabricated bismuth oxide nanoparticle samples are characterized by various analytical tools such as X-Ray diffractometer, Infra-Red spectroscopy, Scanning Electron microscopy and UV-Diffuse Reflectance spectroscopy. The synthesized nanoparticles exhibit excellent photocatalytic activity for the degradation of Rhodamine B dye in aqueous medium. Bismuth silicate exerts more satisfactory catalytic property and outstanding reusability compared to pure bismuth oxide. The superior stability and enhanced activity enables the application of bismuth silicate as a photocatalyst for environmental remediation. 2019, National Institute of Science Communication and Information Resources (NISCAIR). All rights reserved. -
Synthesis of benzothiazinones, benzothiazines and their selenium analogues through novel synthetic routes /
Benzo fused N-heterocyclic scaffolds containing oxygen, sulphur or selenium have found wide interest in the field of drug-discovery. Among these N-heterocycles, benzothiazine, benzoxazine, benzoselenazine and benzothiazinone derivatives are a unique class of compounds and have a larger scope towards the development of efficient and simple synthetic methodologies for their synthesis with readily available substrates. -
Synthesis of Benzothiazinones Benzothiazines and Their Selenium Analogues Through Novel Synthetic Routes
Benzo fused N-heterocyclic scaffolds containing oxygen, sulphur or selenium have found wide interest in the field of drug-discovery. Among these N-heterocycles, benzothiazine, benzoxazine, benzoselenazine and benzothiazinone derivatives are a unique class of compounds and have a larger scope towards the development of efficient and simple synthetic methodologies for their synthesis with readily available substrates. newlineDuring the course of the present thesis a convenient and simple synthetic procedures were developed for the synthesis of benzothiazines, benzoxazines, benzoselenazines and benzothiazinones in an onepot methodology. 2-aryl/alkyl substituted 1,3-benzothiazines and selenazines were synthesized by reacting 2-amino benzyl alcohols and thio or seleno benzamides in the presence of T3P.A reagent controlled methodology was developed for the synthesis of 2-amino substituted 1,3-benzothiazines and oxazines. Initially, various 2-amino benzylalcohols are reacted with newlineisothiocyanates to form the corresponding thioureas. The formed thioureas undergo newlinecyclodehydration in the presence of T3P to yield 2-amino substituted 1,3-benzothiazines newlineand on the other hand molecular iodine facilitates desulfurization of the thiourea to yield 2-amino substituted 1,3-benzoxazines. 2-amino substituted 1,3-benzothiazinones were synthesized by reacting anthranilic acids and isothiocyanates in the presence of EDC.HCl. 2-aryl substituted 1,3-benzothiazinones were synthesized by employing thiobenzamides in the presence of T3P. All the compounds synthesized were characterized by 1HNMR, 13C, Mass spectroscopic (LCMS, HRMS) analysis. Docking studies against TANKYRASE-1 enzyme for colorectal cancer (CRC) and antibacterial studies were also discussed. -
Synthesis of bent-shaped azobenzene main-chain polymers for photo-switching properties
This work presents the synthesis of the new bent-core polymers with siloxane units connected to the one side of azobenzene units. The structure of siloxane-based azobenzene bent-core polymers, 7ac, was elucidated by spectral analysis (nuclear magnetic resonance and Fourier-transform infrared spectroscopy). The results of gel permeation chromatography suggested that all polymers (7ac) showed polydisperse (polydispersity index >1). Besides, the extent of polymerization in the following order: 7a > 7b > 7c, where the degree of polymerization values were 7, 8 and 11, respectively. Polarizing optical microscopy revealed that the bent-core liquid crystal (BCLC) monomers, 6a and 6b, displayed the smectic A phase, whereas BCLC monomer 6c and all siloxane-based main-chain polymers (MCPs) (7ac) were crystalline in nature. The result of ultraviolet-visible spectroscopy demonstrated that all MCPs (7ac) exhibited strong photoisomerization behavior in solution. All polymers (7ac) showed trans to cis isomerization in about 200 s, whereas the reverse process required much longer times ranging from 400 to 520 min in solution. The photo-switching study on azobenzene containing polymers stated that the effect of alkyl chain length and type of central core units on trans to cis isomerization were negligible. In contrast, both parameters influence the cis to trans process in which the photo-switching behavior of these materials may be primarily suitably exploited in the field of photo-induced phenomenon. 2023 Taylor & Francis Group, LLC. -
Synthesis of amine functionalized metal organic framework using H2FIPBB ligand for energy storage application /
Patent Number: 202241023295, Applicant: Sruthi Rajasekaran.
The present invention shows the energy storage application of the Mn-Ni@NH2-h2fipbb MOF using the ligand 4,4:hexafluoroisopropylidene bis- benzoic acid (h2fipbb) under mild conditions. The methodology followed was hydrothermal at 120°C with manganese and nickel metal salts along with the ligand in dimethylformamide (DMF). The development of efficient Mn-Ni@NH2-h2fipbb material is suitable for supercapacitance-energy storage applications, which is the future need for various industrial applications. -
Synthesis of amine functionalized metal organic framework using H2FIPBB ligand for energy storage application /
Patent Number: 202241023295, Applicant: Sruthi Rajasekaran.
The present invention shows the energy storage application of the Mn-Ni@NH2-h2fipbb MOF using the ligand 4,4:hexafluoroisopropylidene bis- benzoic acid (h2fipbb) under mild conditions. The methodology followed was hydrothermal at 120°C with manganese and nickel metal salts along with the ligand in dimethylformamide (DMF). The development of efficient Mn-Ni@NH2-h2fipbb material is suitable for supercapacitance-energy storage applications, which is the future need for various industrial applications. -
Synthesis of 4H-3,1-Benzothiazin-4-Ones via C-N/C-S Bond Forming Reactions
A Phosphine-free and effective process has been expressed for the formulation of N,S-heterocycles following a C-N/C-S bond forming reactions. The described process operates through EDC-HCl-mediated heterocyclization of diverse isothiocyanates and bis-nucleophiles to deliver 1,3-thiazinone derivatives, which eliminates the use of hazardous reagents. The developed protocol was found applicable over a wide range of substrates in delivering N,S-heterocycles in excellent yields at room temperature and short reaction time. 2022 Taylor & Francis Group, LLC. -
Synthesis of 1, 8-Naphthyridine-3-Carbonitriles under solvent-free conditions using ceric ammonium nitrate
1,8-naphthyridines are synthesized using a four-component, one-pot approach. This method includes the reaction of aromatic aldehyde, malononitrile, 1,6-dimethylpyridin-2(1H)-one, substituted aniline in a solvent-free condition catalyzed by Ceric Ammonium Nitrate (CAN). Contrary to the reported literature, this distinct method houses several promising factors to the same degree as solvent-free reaction conditions, shorter reaction duration, excellent yields, and a straightforward extraction process. 2023 Elsevier Ltd. All rights reserved. -
Synthesis methods of chitosan nanoparticles: A review
Biopolymeric nanoparticles are found to be very effective in potential applications in different fields, especially in biomedical field. Chitosan nanoparticles (CSNPs) are one of those kind of nanoparticle with great research potential owing to its nontoxicity, biodegradability, and high permeability. The extraction of chitosan biopolymer and the production of CSNPs are both vibrant research areas. Emulsification, complexing, phase inversion etc. are the conventional synthesis methods; new synthesis methods are being developed to overcome the disadvantages of traditional approaches. Here we provide a glimpse into the methodological and mechanistic underpinnings of the synthesis methods of CSNPs. This chapter provides a complete overview of the synthesis methods used for the production of CSNPs, their benefits, drawbacks, and obstacles, as well as their future prospects. 2025 Elsevier Ltd. All rights reserved. -
Synthesis and Studies on Partially Stabilized Zirconia and Rare-Earth Zirconate Pyrochlore Structured Multilayered Coatings
This work is focused on the thermal fatigue behaviour studies of ceramic coatings, as TBC (Thermal Barrier Coating) system, its importance in determining the thermo-mechanical properties and service-life estimation of the coatings when exposed to elevated operating temperatures. Commercial 6-8%Yttria stabilized zirconia (YSZ) top coat (TC) and NiCrAlY bond coat (BC) in (a) conventional YSZ (BC and TC), (b) multi-layered functionally graded materials (FGM) i.e., BC-blend (50BC+50TC)-(TC) configuration and (c) lab synthesized Zirconia based pyrochlore (Lanthanum Zirconate-LZ) were the coating materials involved. Nickel based super alloy Inconel 718 substrates were coated by using Atmosphere Plasma Spray (APS) system with three different (varying power) plasma spray parameters. All the sides of the 25mm x 10mm x 5mm thick substrates were completely covered with the bond coat and ceramic coating. FGM configuration was spray coated only on one side of the Inconel flat plates. Thermal shock cycle tests were performed on the coated specimen by following the ASTM B214-07 guidelines which comprised of introducing the coated specimen in a muffle furnace at 1150C, held in it for 2 minutes before removing from furnace followed by forced fan air cooling (one shock cycle). The specimen were periodically subjected to visual inspection for faults, before continuing the shock cycles, until the coating flaked off or cracked or detached from substrate. Cross section metallographic samples were prepared and analysed under SEM (Scanning Electron Microscope) and Energy Dispersive spectroscope (EDS) to study the as-sprayed coating morphology and interface quality, measure coating thickness, study defects characteristics and the chemical composition. Crystal structural phases were analysed using X-Ray Diffraction (XRD). 2019 Elsevier Ltd. -
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Synthesis and physico-chemical characterization of ZnS-based green semiconductor: A review
One-dimensional (1D) semiconductor nanostructures have been attracting a great deal of attention because of their excellent electronic and optoelectronic performance. Zinc sulfide (ZnS) nanostructures have attracted increasing attention because of their potential application in both conditional optical devices and new generation of green nanostructure semiconductors because of their special structure-related physical and chemical properties. Synthetic form of ZnS can be transparent, and it is used as a window for visible optics, infrared optics, and functional materials. In this chapter, the detailed studies of synthesis, characterization of crystals, and noncrystalline behavior is reported. The crystal structure of semiconductor and its morphological studies are compared and fabrication methods will be described. The major parameters that influence on ZnS doped with metal ions and rare earth ions and its optoelectronic properties will be carefully analyzed. In addition, the primary application of ZnS micro- and nanocrystals will be described. At the end, the predicted future applications and development directions of doped and undoped ZnS nanocrystals will be given. 2023 Elsevier Ltd. All rights reserved. -
Synthesis and photophysical properties of a novel phthalimide derivative using solvatochromic shift method for the estimation of ground and singlet excited state dipole moments
A novel phthalimide derivative, 2-{4-[(1H-1,2,4-triazol-1-yl)methyl]phenyl}-1Hisoindole-1,3(2H)-dione (TMPID) containing an isoindole moiety was synthesized by the cyclisation of 2-({4-[(1H-1,2,4-triazol-1-yl)methyl]phenyl}carbamoyl)benzoic acid (TMPCB). The absorbance and fluorescence spectra of the derivative were recorded in fifteen different solvents to investigate their solvatochromic behaviour and dipole moments. Different solvent correlation methods, like the BilotKawski, LippertMataga, Bakhshiev, KawskiChammaViallet and Reichardt methods were employed to estimate the singlet excited and ground state dipole moments. Using multiple regression analysis, solute-solvent, specific and non-specific interactions were analyzed by means of Kamlet-Abboud-Taft and Catalan parameters. Computational studies were performed using time dependent density functional theory (TD-DFT) in order to calculate ground state dipole moment, atomic charges and frontier molecular orbital energies in solvent phase. Experimental and computational studies indicate that the singlet excited state dipole moment of TMPID is greater than the ground state dipole moment. The chemical stability of the derivative was determined by means of chemical hardness (?) using HOMOLUMO energies. From TD-DFT computational analysis, reactive centres in the molecule were evaluated based on molecular electrostatic potential (MESP) 3D plots. 2016 Elsevier B.V. -
Synthesis and Nuclear Magnetic Resonance Studies of 2-Thiophenecarboxaldehyde Nicotinic Hydrazone and 2-Thiophenecarboxaldehyde Benzhydrazone
Synthesis and NMR spectral studies of bidentate N and S heterocycles of 2-thiophenecarboxaldehyde nicotinic hydrazone and 2-thiophenecarboxaldehyde benzhydrazone have been carried out. The compounds, 2-thiophenecarboxaldehyde nicotinic hydrazone and 2-thiophenecarboxaldehyde benzhydrazone were synthesized by reacting stoichiometric quantities of nicotinic hydrazide and benzhydrazide with 2-thiophene carboxaldehyde in methanol in the presence of glacial acetic acid at refluxing temperature. Upon cooling the reaction mixture, the products were obtained as colorless solids. 1H, 13C, 1H-1H COSY, and 1H-13C HSQC experiments have been conducted to characterize the compounds. 2020 Malaysian Institute of Chemistry. All rights reserved. -
Synthesis and Multifaceted Exploration of 4-Phenylpiperidin-4-ol Substituted Pyrazole: Photophysical Insights with Biological Activity
In this study, we successfully synthesized a pyrazole derivative, specifically 4-phenylpiperidin-4-ol substituted pyrazole (CHP), through the reaction of Grignard reagents in combination with pyrazole. This newly synthesized molecule was subjected to a comprehensive evaluation for both its photophysical and biological applications. Notably, CHP exhibited promising invitro antifungal and antibacterial activities, primarily attributed to the presence of the 4-phenylpiperidin-4-ol moiety and resulting component contributed to an enhanced absorption rate of lipids, thereby improving the pharmacological activity of CHP. This correlation between structure and function was further supported by the outcomes of structure-activity relationship studies. Additionally, we conducted in silico studies to examine the molecular interactions of the synthesized molecule with key proteins, including DNA Gyrase, Lanosterol 14 ?-demethylase, and KEAP1-NRF2. The results unveiled robust binding interactions at specific sites within these proteins, indicating potential therapeutic relevance. Furthermore, the photophysical properties of the synthesized compounds were thoroughly investigated using the ab-initio technique. This involved the determination of ground state optimization and HOMO-LUMO energy levels, all calculated with the DFT-B3LYP-6-31G(d) basis set. The assessment of the theoretically estimated HOMO-LUMO value provided insights into the global chemical reactivity descriptors, revealing that the synthesized molecule boasts a highly electronegative and electrophilic index. Taken together, our findings suggest that pyrazole derivatives with 4-phenylpiperidin-4-ol substitutions exhibit promising applications in both photophysical and biological contexts. 2024 Ghaferah H. Al-Hazmi et al., published by Sciendo. -
