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Synthesis and electrochemical studies of 1,1-binaphthyl-2,2-diol for aqueous rechargeable lithium-ion battery applications
The constant increase in the utilization of lithium-ion batteries (LIBs) in various field applications, including electrical vehicles and electronic devices, has led researchers to focus on their multiple path developments to obtain new electrode materials. The practical development of these electrode materials, based on organic and inorganic moieties, is challenging for various groups of LIB scientists. The concept of organic electrode materials is highly competitive with inorganic electrode materials because of the accessibility of more active sites with structural diversity, high energy and power density, environmental friendliness potential sustainability, and low cost. Herein, 1,1-binaphthyl-2,2-diol (BINOL) is investigated as an organic electrode material that contains two hydroxyl groups that act as active centers. The oxidative coupling process is employed to synthesize BINOL and so obtained product was characterized by using FT-IR, 1H-NMR and MASS techniques. The electrochemical investigations were carried out using sat. Li2SO4 electrolytic medium at three-electrode cell system. The Cyclic voltammetry (CV) has provided information on the anodic behavior of the material and its stability studied at different scan rates. The battery performance of the cell BINOL | Sat. Li2SO4 | LiMn2O4 by galvanostatic charge-discharge potential limit (GCPL) shows 197/171mAhg?1 specific capacity and 90% columbic efficiency. The electrochemical kinetic obtained by potentiostatic electrochemical impedance spectroscopy (PEIS) shows a semi-infinite diffusion process. 2024 Elsevier B.V. -
Synthesis and crystal structure of 1,7-bis(4-methoxyphenyl)-4-(1,3- dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione
The synthesis and crystal structure of 1,7-bis(4-methoxyphenyl)-4-(1,3- dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione is described. This compound crystallizes in the space group P21 with unit cell parameters a = 14.207 b = 7.752(1) c = 19.473(1) ? = 91.00(3), with two molecules in the asymmetric unit. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in this compound. The cinnamoyl groups are organized parallel to each other due to the push-pull nature of the ketenedithioacetal functionality. 2010 Springer Science+Business Media, LLC. -
Synthesis and Characterization of WO3 Nanostructures by the Solvothermal Method for Electrochromic Applications
In this study, a tungsten trioxide (WO3) thin film was deposited by direct current (DC) sputtering onto a fluorine-doped tin oxide (FTO) substrate as the seed layer at an oxygen partial pressure of 8 10?4mbar. A simple solvothermal method involving tungsten hexacarbonyl (W(CO)6), ethanol (C2H5OH), and hydrochloric acid (HCl) was used to synthesize vertically stacked nanoscale WO3 hierarchical structures on WO3 seed-layered FTO. After the deposition process, the FTO samples with nanostructures were subjected to annealing in air at 400C for 4 h. After annealing, the surface morphology, structural characteristics, and optical and electrochromic properties of the grown nanostructures were investigated using scanning electron microscopy (SEM), x-ray diffraction (XRD), Raman spectroscopy, UVvisible spectroscopy, and electrochemical analysis. From the XRD analysis, all the diffraction patterns were ascribed to a monoclinic phase. The SEM analysis showed that films grown with 5?L HCl had a nanoflower structure compared to the films grown with 0?L HCl and 20?L HCl. The nanoflower-structured films showed a higher cathodic peak current (?2.22mA), diffusion coefficient (5.43 10?9 cm2/s), and coloration efficiency (23.6 cm2/C). The increased electrochromic characteristics were attributed to the nanostructured films, which enhanced the diffusion of H+ ions by providing a large surface area during the charge transfer process. The Minerals, Metals & Materials Society 2024. -
Synthesis and Characterization of Vanadyl Complexes of Heterocyclic Acid Hydrazones
Two acid hydrazones, Furan-2-carbaldehyde nicotinic hydrazone and Furan-2-carbaldehyde benzhydrazone have been synthesised and they are characterized by elemental analysis, IR, NMR and UV spectral analysis. Vanadyl complexes of these two hydrazones were synthesised and characterised by elemental analysis, IR, UV, EPR, molar conductivity and magnetic susceptibility measurements. Spectral data indicates the square pyramidal geometry for the monomeric ve coordinated oxovanadium (IV) complexes with the general formula [VO(L)(OCH3 )].The vanadium complex of the acid hydrazone was studied for its catalytic activity. The complex was found to be a good catalyst in quinoxaline synthesis. -
Synthesis and characterization of porous, mixed phase, wrinkled, few layer graphene like nanocarbon from charcoal /
Russian Journal Of Physical Chemistry A, Vol.89, Issue 13, pp.2438-2442, ISSN No: 0036-0244. -
Synthesis and characterization of porous, mixed phase, wrinkled, few layer graphene like nanocarbon from charcoal
A technique to synthesis wrinkled graphene like nano carbon (GNC) from charcoal is reported in the current study. The charcoal produced by thermal decomposition and is intercalated by Hummers method. It is separated by centrifugation and sonication to get few layer graphene sheets. The structural and chemical changes of the nanostructure is elucidated by Raman spectroscopy, TEM, SEM-EDS and XPS. Raman spectra revealed the existence of highly graphitized amorphous carbon, which is confirmed by the appearance of five peaks in the deconvoluted first order Raman spectra. The SEM analysis reveals the formation of large area graphene sheets with nano-porous structure in it. The TEM/SAED analysis exhibits the presence of short range few layer graphene. 2015 Pleiades Publishing, Ltd. -
Synthesis and characterization of Poly-Vinyl Alcohol-Alumina composite film: An efficient adsorbent for the removal of Chromium (VI) from water
Composite poly vinyl alcohol-alumina films were synthesized by a novel eco-friendly route in the absence of template. The physico-chemical nature of the synthesized film was studied using different characterization techniques. The poly vinyl alcohol-alumina composite film was found to be an efficient adsorbent for the removal of Chromium (VI) at higher concentrations from water. The preparation conditions were optimized to synthesize an efficient adsorbent film for the removal of chromium. The surface properties, chemical composition and amorphous nature of the film confirmed by different characterisation techniques attributes to the chromium removal efficiency of the film. Poly vinyl alcohol-alumina films are economically cheap, easy to prepare, efficient adsorbent for removal of chromium (VI) eco-friendly in nature and reusable with effortless regeneration methods. 2022 -
Synthesis and characterization of heterocyclic derivatives and studies on their photophysical properties
Photophysical properties such as absorption, fluorescence, quantum yields and lifetime of fluorescent heterocyclic compounds have been a subject of extensive research interest. Absorption and fluorescence emission of fluorescent molecules results in electronic transitions between ground and singlet excited state. The bathochromic or hypsochromic spectral shift brings a considerable change in dipole moment of both the electronic states through solute-solvent interactions. We have synthesized some heterocyclic compounds and studied thier photophysical properties. Different derivatives such as Schiff base, chalcone, maleimide and pyranopyrazole were synthesized and characterized by FTIR, 1H NMR, 13C NMR, mass spectrometry and elemental analysis. Photophysical properties of synthesized compounds have been studied through absorption and fluorescence spectroscopy and DFT calculations. We have used solvatochromic approaches such as Bilot-Kawski, LippertMataga, Bakhshiev, Kawski-Chamma-Viallet and Reichardt's solvent polarity parameters to evaluate dipole moments of ground state and singlet excited state of the synthesized heterocyclic compounds. The influence of specific and non-specific interactions on spectral properties was also investigated by using Kamlet-Abboud-Taft and Catalan multiple linear regression equations. X-ray diffraction analysis of hydroxyl Schiff base derivative has been carried out due to the presence of strong inter and intra molecular hydrogen bonding. Solvatochromic analyses of synthesized compounds were done using Bilot-Kawski, Lippert-Mataga, Bakhshiev, Kawski- Chamma-Viallet and Reichardt methods. All Solvatochromic graphs have been plotted for spectral parameters against solvent polarity parameters using Origin 8 software. The obtained experimental results from all methods were compared with theoretical results. The correlation coefficient between microscopic solvent polarity parameter and spectral Stokes-shifts were higher in comparison to bulk solvent polarity functions. Graphs for each molecule provided good correlation based on least square analysis. Dipole moment values of ground and excited states were calculated using slopes of different solvatochromic methods. Higher value of singlet excited state dipole moment indicated that the molecules were more polarised in the singlet excited state. Kamlet-Abboud-Taft and Catalan multiple linear regression (MLR) analyses were used to analyse the solvent effects on absorption, emission and difference in spectral energies of the synthesized molecules. Single point method was used to calculate the quantum yields of the synthesized compounds in ethanol using an ethanolic solution of anthracene as a reference compound. Edwards atomic increment method was applied to calculate the Onsager cavity radii of all the molecules using van der Waals volume. DFT/TD-DFT was used for quantum mechanical calculations of all the molecules. The geometrical structures of the synthesized molecules were optimized using B3LYP/6-311G(d, p) basis set. The positions of HOMO-LUMO orbitals were identified and the band gaps for all the molecules were calculated. Mulliken atomic charges and electrostatic potential surface (MEP) have also been evaluated for all the molecules to identify the ICT pathway and evaluate electrophilic and nucleophilic reactive sites around the molecules . The fluorescence quenching studies of a chalcone derivative by aniline in n-butanol and 1,4-dioxane was performed at 25 ? C which indicated that quenching reactions are diffusion limited. -
Synthesis and characterization of graphene oxide and reduced graphene oxide membranes for water purification applications
Graphene oxide and reduced graphene oxide-based laminar membranes have been receiving increased attention for its novel filtration applications. In the present work, graphene oxide (GO) solution is synthesized by modified Hummers method and coated on cellulose nitrate by vacuum filtration technique. Further, reduced graphene oxide (rGO) membranes are fabricated by the controlled reduction of GO membrane using vitamin C solution at 60 C. The formation of GO and rGO is confirmed from Raman, FTIR, and UVVis spectroscopy studies. Morphology and thickness of the membranes are investigated using surface and cross-sectional FESEM images. The filtration study showed that rGO membrane has higher water flux (52 L m?2h?1) than GO (40 L m?2h?1) membrane at differential pressure of 0.3MPa. Moreover, both membranes show congo red rejection of 96%. Prior studies showed that water flux decreased upon reduction of GO membrane which hindered the filtration properties of the membrane. Current work indicates that controlled reduction of GO leads to an enhancement in water flux, maintaining the dye rejection ratio. Graphical Abstract: [Figure not available: see fulltext.] 2023, Qatar University and Springer Nature Switzerland AG. -
Synthesis and characterization of graphene filled PC-ABS filament for FDM applications
Present investigation focuses on development of graphene filled PC-ABS filament for Fused Deposition Modeling applications. Compounding and twin screw extrusion was employed to synthesis graphene filled FDM filament of 1.75mm diameter. Percentage of graphene was varied from 0.1 vol% to 0.25 vol% in steps of 0.05. Developed filaments were subjected to SEM studies, dimensional accuracy and density measurements. In order to achieve filament of 1.75mm diameter, filament extrusion temperature was optimized using Taguchi's L25 orthogonal array, microstructure shows homogeneous dispersion of graphene particles in PC-ABS matrix, density decreases with increased content of graphene particles. 2018 Author(s). -
Synthesis and characterization of flyash reinforced polymer composites developed by Fused Filament Fabrication
Fused filament fabrication (FFF) has seen an upsurge in its utilization towards development of tailored made materials of polymer base. The advancement and diversity in fabricating the polymer composite parts by using FFF has seen the embracement of this technology in wider aspects, ranging from automotive, aerospace, construction and has marched towards day to day requirements. This research article focuses on development of polymer composite; by using flyash (FA), an industrial waste produced during coal combustion, as reinforcement in Acrylonitrile butadiene styrene (ABS) matrix, to study the physical and mechanical properties. FA, which is primarily made up of metal oxides, plays an imperative role as reinforcement. Easily and abundantly available, FA is being used in several applications to reduce the landfills utilization and also helps the environment. In this study FA was added as reinforcement in 5 and 10 wt. % respectively to ABS matrix and was developed into filament of 1.75 mm diameter. The developed ABS + FA polymer composite using FFF, were analyzed for physical and mechanical properties as per American Society for Testing and Materials (ASTM) standards. Microstructure studies were carried out for the developed composite to understand their behavior in enhancing the dimensional accuracy and tensile strength with incremental addition of FA up to 10 wt%. Tensile strength was enhanced by 28.19% and 36.13% for ABS + 5wt. % FA and ABS + 10wt. % FA respectively. Dimensional stability was also enhanced. Similarly, surface roughness analysis was carried out and it was observed to reduce with addition of FA. The surface roughness measurements provided suitable results of decrement by 9.64% and 14.6% for ABS + 5wt. % FA and ABS + 10wt. % FA respectively. Overall, the usage of FA along with FFF, has paved a path in sustainable and green technology in manufacturing. 2022 The Author(s). -
Synthesis and characterization of cyclopentadithiophene and thienothiophene-based polymers for organic thin-film transistors and solar cells /
Macromolecular Research, Vol.26, Issue 10, pp. 1-8, ISSN: 1598-5032 -
Synthesis and Characterization of Cyclopentadithiophene and Thienothiophene-Based Polymers for Organic Thin-Film Transistors and Solar Cells
Novel donor-donor type alternating copolymers (8CDT-TT and 16CDT-TT) derived from cyclopentadithiophene (CDT) and thienothiophene (TT) moieties that differ from solubilizing side chains were successfully synthesized and characterized. After the synthesis of CDT-TT-based conjugated polymers with dioctyl and dihexadecyl side chains, their optical, thermal, structural and semiconducting properties were investigated. Organic thin-film transistors fabricated from 8CDT-TT and 16CDT-TT exhibit carrier mobilities as high as 3.920-4 and 1.050-3 cm2V-1s-1, respectively. Bulk heterojunction solar cells fabricated using a polymer:PCBM blend ratio of 1:3 exhibit power conversion efficiencies of 2.12 and 1.84% for 8CDT-TT and 16CDT-TT, respectively. 2018, The Polymer Society of Korea and Springer Nature B.V. -
Synthesis and characterization of Cr2AlC MAX phase for photocatalytic applications
MAX phase, a layered ternary carbide/nitride, displays both ceramic and metallic properties, which has significantly attracted the materials research. In this work, Cr2AlC MAX phase powder with high purity was fabricated via a facile and cost-effective pressure-less sintering methodology and utilized for photocatalytic degradation of different organic pollutants for the first time. Various characterization techniques were used for confirming the morphological and other physico-chemical properties of the catalyst. Cr2AlC MAX phase with a low band gap of 1.28 eV has shown 99% efficiency in the degradation of malachite green, an organic pollutant under visible light irradiation. The scavenger studies conclude that, O2?and h+ as the active species during the photocatalytic reaction. Furthermore, the kinetic study revealed that the reaction obeys pseudo-first-order kinetics and can be reused for four cycles without losing the activity. This novel approach can give new insight into the potential application of MAX phase materials in the field of wastewater treatment under visible light irradiation. 2021 Elsevier Ltd -
Synthesis and characterization of Chitosan-CuO-MgO polymer nanocomposites
In the present work, we have synthesized Chitosan-CuO-MgO nanocomposites by incorporating CuO and MgO nanoparticles in chitosan matrix. Copper oxide and magnesium oxide nanoparticles synthesized by precipitation method were characterized by X-ray diffraction and the diffraction patterns confirmed the monoclinic and cubic crystalline structures of CuO and MgO nanoparticles respectively. Chitosan-CuO-MgO composite films were prepared using solution- cast method with different concentrations of CuO and MgO nanoparticles (15 - 50 wt % with respect to chitosan) and characterized by XRD, FTIR and UV-Vis spectroscopy. The X-ray diffraction pattern shows that the crystallinity of the chitosan composite increases with increase in nanoparticle concentration. FTIR spectra confirm the chemical interaction between chitosan and metal oxide nanoparticles (CuO and MgO). UV absorbance of chitosan nanocomposites were up to 17% better than pure chitosan, thus confirming its UV shielding properties. The mechanical and electrical properties of the prepared composites are in progress. 2018 Author(s). -
Synthesis and characterization of chitosan nanofibers for wound healing and drug delivery application
Chitosan has emerged as a biodegradable, absorbable, non-toxic, biocompatible biopolymer for wound healing and drug delivery applications. Chitosan can be converted to nanofibers which have higher potential for wound healing and drug delivery applications as compared to chitosan nanoparticles and nanocomposites. Due to these properties chitosan nanofiber has emerged as a promising candidate for biomedical research. In the recent decades it has been observed that several studies reported about the production and medical applications of chitosan nanofibers. Although, preparation and application of chitosan nanofibers is easy. But there are several challenges and bottlenecks associated with its practical application and large-scale production. The presented review is a comprehensive discussion on the major challenges and bottlenecks associated with chitosan nanofibers synthesis and their practical applications in biomedical research. It discusses critically about the issues related to the chitosan nanofibers solubility, stability, mechanical strength, absorption and drug release properties, and its scale up hinderances. Moreover, the review presents an insight into the future recommendations on considering the parameters associated for development of an efficient, sustainable, and promising biopolymer. 2023 Elsevier B.V. -
Synthesis and characterization of CeO2/Bi2O3/gC3N4 ternary Z-scheme nanocomposite
An effective and facile phytogenic method was used to prepare CeO2/Bi2O3 and CeO2/Bi2O3/gC3N4 composites using Eichhornia crassipes phytoextract. The synthesized catalysts were characterized using techniques such as XRD, FTIR, UV-DRS, PL, SEM-EDAX, XPS, zeta potential, and TGA. These catalysts showed diverse photocatalytic and optical properties due to the alteration in the bandgap. The synthesized composites exhibited good photocatalytic activity by degrading Malachite green (MG) dye. The increase in the photocatalytic activity could be attributed to the p-n heterojunction of the catalysts with efficient charge separation and strong oxidative ability. The modified photocatalysts showed excellent catalytic activity and reusability under visible light. The superior efficiency and its applications in environmental remediation make these catalysts a potential candidate for photocatalysis. 2020 The American Ceramic Society -
Synthesis and characterization of carbon nanospheres from hydrocarbon soot
Foreseeing the upcoming era of the carbon nanomaterials and their revolutionary applications, we have identified and explored the structural parameters of five effective precursors of the same-carbon black, soot obtained by the thermal decomposition of kerosene, diesel, paraffin wax and lubricant oil. Micro-Raman spectroscopy, Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning Electron Microscopy, Electron dispersive spectroscopy (EDS) and elemental analysis are employed for the structural and morphological characterization of the nanomaterials formed. The average lateral size (La), stacking height (Lc) and interlayer spacing (d002) of the crystallite structures calculated from the X-ray intensities are found to be ranging from 4.3-5.9 nm, 0.63-2.40 nm and 3.10- 3.68 respectively. La values determined by Raman and XRD analysis are in very good agreement thereby reinforcing the nanocrystalline structure of the samples. The very low I20/I26 ratio obtained reveals a relatively low amount of disorder in the nanostructures. Nanomaterials formed have the morphology of non-uniform nanospheres with diameter varying between 26-100 nm. EDS and elemental analysis confirms the absence of metal impurities. FTIR spectra of the samples shows the presence of stretching vibrations of -OH bonds, aliphatic -CH, -CH2 and -CH3 absorptions, C=C and -CH absorptions of aromatic structures. 2012 by ESG. -
Synthesis and Characterization of Carbon Nanospheres from Hydrocarbon Soot
International Journal of Electrochemical Science Vol. 7, Issue 10, pp. 9537-9549, ISSN No. 1452-3981 -
Synthesis and Characterization of Carbon Nanomaterial Derived from Anthracite
Among various storage devices, carbon based supercapacitors grabs the recent trends in the electronic devices. The present research work describes the synthesis of carbon nanomaterials derived from anthracite by using staudenmaier method. Anthracite was used as a precursor because of its high carbon content. The structural and chemical complex formation carried out by using XRD and FTIR confirms the formation of CNT's. The calculated value obtained from the XRD peaks confirms the formation of multilayer carbon nano-materials. The electrode was prepared by coating synthesized CNT on copper rod. The electrochemical performance of prepared working electrode was carried out by using cyclic voltammetric performance. Electrode characterization was performed for different scan rates 10, 20, 30 and 50 mV/sec in a potential window from-0.08 to 0.2V. The CV curves represents symmetric nature which imply that electrode material have stable capacitive process. 2019 Elsevier Ltd.