scholarly journals Green Synthesis and Characterization of Gallium(III) Sulphide (α-Ga2S3) Nanoparicles at Room Temperature

Nano Hybrids ◽  
2014 ◽  
Vol 6 ◽  
pp. 37-46 ◽  
Author(s):  
Tansir Ahamad ◽  
Saad M. Alshehri
Keyword(s):  
Green Synthesis ◽  
Band Gap ◽  
Raman Spectra ◽  
Room Temperature ◽  
Optical Band Gap ◽  
Blue Shift ◽  
Synthesis And Characterization ◽  
Spectroscopic Techniques ◽  
Sodium Thiosulphate

Two different batches of Gallium (III) sulphide nanocrystals, (α-Ga2S3)1 and (α-Ga2S3)2 were synthesized at room temperature by the reaction of Gallium (III) chloride with sodium thiosulphate in water for 10 and 20 min respectively. The resultant nanoparticles were characterized by different spectroscopic techniques. TEM micrographs showed well-defined, close to hexagonal particles, and the lattice fringes in the HRTEM images confirmed their nanocrystalline nature. The sizes of (α-Ga2S3)1 and (α-Ga2S3)2 were 12 and 35 nm respectively with similar morphologies. Optical band gap energies (3.43 eV/3.41 eV) and photoluminescence peaks 635/641 nm (red shift) and 414/420 nm (blue shift) of the synthesized α-Ga2S3 nanocrystals suggest that they may be promising photocatalysts. Raman spectra for the α-Ga2S3, shows very sharp bands at 119, 135 and 148 cm-1 due to Ga-S2 scissoring.

Synthesis and characterization of ZnO-reinforced with graphene nanolayer nanocomposites: electrical conductivity and optical band gap analysis

2019 ◽  
Vol 6 (9) ◽  
pp. 095602 ◽  
Author(s):  
Ömer Güler ◽  
Seval Hale Güler ◽  
Öyküm Başgöz ◽  
M Gökhan Albayrak ◽  
I S Yahia
Keyword(s):  
Electrical Conductivity ◽  
Band Gap ◽  
Optical Band Gap ◽  
Gap Analysis ◽  
Synthesis And Characterization

Efficient Synthesis and Characterization of Novel Substituted 3-Benzoylindolizine Analogues via the Cyclization of Aromatic Cycloimmoniumylides with Electrondeficient Alkenes

2018 ◽  
Vol 15 (3) ◽  
pp. 388-395 ◽  
Author(s):  
Katharigatta N. Venugopala ◽  
Sandeep Chandrashekharappa ◽  
Subhrajyoti Bhandary ◽  
Deepak Chopra ◽  
Mohammed A. Khedr ◽  
...  
Keyword(s):  
Room Temperature ◽  
Synthesis And Characterization ◽  
Resonance Spectroscopy ◽  
Spectroscopic Techniques ◽  
Pharmacological Properties ◽  
Liquid Chromatography Mass Spectrometry ◽  
Efficient Synthesis ◽  
Ray Method ◽  
X Ray

Background: Indolizine pharmacophore is known to exhibit various promising pharmacological properties such as analgesic, anticancer, antihistaminic, antidiabetic, anti-inflammatory, antileishmanic, antimicrobial, antimutagenic, antioxidant, antitubercular, antiviral, larvicidal and herbicidal activities. Objective: In the present investigation, it was envisaged to synthesize a series of novel ethyl-7-substituted-3-(4- substituted benzoyl)-2-substituted indolizine-1-carboxylates by employing chromium(IV)oxide as dehydrogenating agent with triethylamine combination. Method: Synthesis of a series of proposed polysubstituted indolizines by employing chromium(IV)oxide as dehydrogenating agent with triethylamine combination. Final compounds were characterized by spectroscopic techniques viz fourier-transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, liquid chromatography- mass spectrometry, elemental analysis and selected title compound diethyl-3-(4- cyanobenzoyl)indolizine-1,2-dicarboxylate by single crystal X-ray method. Results: Aromatic cycloimmoniumylides undergo smooth cyclization with electron-deficient alkenes in the presence of triethylamine and DMF at room temperature to afford intermediates ethyl 7-substituted-2- substituted-3-(4-substituted benzoyl)-1,2,3,8a-tetrahydroindolizine-1-carboxylates, which on dehydrogenation with chromium(IV)oxide to obtain the title compounds ethyl-7-substituted-3-(4-substituted benzoyl)-2- substituted indolizine-1-carboxylates. Conclusion: The research was focused on developing an efficient protocol for the synthesis of a novel series of ethyl 3-substituted benzoyl-7-substituted-2-substituted indolizine-1-carboxylates with suitable pharmacological properties in good to excellent yields.

Green Synthesis and Characterization of Iron Nanoparticles from Holy Basil Leaves and Mint Leaves

2016 ◽  
Vol 675-676 ◽  
pp. 121-124
Author(s):  
Wanida Wonsawat ◽  
Yuwadee Panprom
Keyword(s):  
Optimum Condition ◽  
Green Synthesis ◽  
Chemical Method ◽  
Room Temperature ◽  
Iron Nanoparticles ◽  
Synthesis And Characterization ◽  
Toxic Chemical ◽  
Chemical Reagent ◽  
Holy Basil

In this study, Iron nanoparticles (FeNPs) were synthesized by green chemical method. A reducing and stabilizing agent from plant were used instead of toxic chemical reagent. It was observed that FeNPs was obtained at room temperature (25-35 °C) using bioreducing agent without voltammetric method. The optimum condition for FeNPs synthesis was studied. The nanoparticles have been preliminary characterized by UV-vis spectrophotometry.

scholarly journals The effects of doping on the structural, optical and electric properties of Zn4Sb3 material

2016 ◽  
Vol 81 (3) ◽  
pp. 323-332 ◽  
Author(s):  
Mirela Vaida ◽  
Narcis Duteanu ◽  
Ioan Grozescu
Keyword(s):  
Band Gap ◽  
Room Temperature ◽  
Optical Band Gap ◽  
Visible Range ◽  
X Ray Diffraction ◽  
X Ray ◽  
Absorbance Spectra ◽  
Semiconducting Behavior ◽  
Scanning Electron

This paper presents results of the investigations regarding the obtaining and the characterization of the thermoelectric material Zn4Sb3 and (Zn1-xMx)4Sb3 where M = Ag and / or Sn. Obtaining of the materials was realized by melting high purity precursors into an oven where were kept isothermally for 12 hours at 1173 K. X-ray diffraction and scanning electron microscopy were used for structural and morphologic characterization. Optical band gap for each sample was determined from absorbance spectra recorded in the visible range 240-400 nm at room temperature. Electrical resistivity as function of temperature was measured and the electrical band gap was estimated for each of the obtained samples. The semiconducting behavior of the materials was reflected by these.

Laboratory synthesis and characterization of Knasibfite K3Na4[SiF6]3[BF4] and the homologous Ge compound K3Na4[GeF6]3[BF4]

2020 ◽  
Vol 235 (8-9) ◽  
pp. 247-254
Author(s):  
Jascha Bandemehr ◽  
Josefin Klippstein ◽  
Sergei I. Ivlev ◽  
Malte Sachs ◽  
Florian Kraus
Keyword(s):  
Crystal Structure ◽  
Phase Transition ◽  
Raman Spectra ◽  
Hydrofluoric Acid ◽  
Room Temperature ◽  
Synthesis And Characterization ◽  
Infrared And Raman Spectra ◽  
Monoclinic Structure ◽  
Laboratory Synthesis

AbstractHerein we present the synthesis, crystal structure, and the infrared and Raman spectra of K3Na4[SiF6]3[BF4]. The compound also occurs in nature as the mineral Knasibfite. We obtained it from the reaction of stoichiometric amounts of SiO2, Na[BF4], K2CO3, and Na2CO3 in hydrofluoric acid at room temperature. Hydrofluorothermal synthesis at 200 °C lead to a product of higher purity. Knasibfite is colorless and crystallizes in space group Im 2m with a = 5.546(2), b = 9.261(2), c = 17.184(4) Å, V = 882.5(4) Å3, Z = 2, at T = 400(2) K. At 342 K a phase transition to a monoclinic structure was observed (I 2, a = 5.5003(6), b = 9.0890(9), c = 17.0048(2) Å, β = 90.041(9)°, V = 852.2(2) Å3, Z = 2, T = 100(2) K). By replacing SiO2 with GeO2 as a starting material K3Na4[GeF6]3[BF4] was obtained. This compound also crystallizes in form of two polymorphs, both of which are isotypic to the respective ones of K3Na4[SiF6]3[BF4].

Characterization of intergranular cuprous oxide in polycrystalline YBa2Cu3O7-x

1988 ◽  
Vol 46 ◽  
pp. 880-881
Author(s):  
Bradley L. Thiel ◽  
Chan Han R. P. ◽  
Kurosky L. C. Hutter ◽  
I. A. Aksay ◽  
Mehmet Sarikaya
Keyword(s):  
Grain Boundary ◽  
Cuprous Oxide ◽  
Room Temperature ◽  
Boundary Phase ◽  
Spectroscopic Techniques ◽  
Transition Width ◽  
Practical Applications ◽  
Thin Foils ◽  
Superconducting Oxides

The identification of extraneous phases is important in understanding of high Tc superconducting oxides. The spectroscopic techniques commonly used in determining the origin of superconductivity (such as RAMAN, XPS, AES, and EXAFS) are surface-sensitive. Hence a grain boundary phase several nanometers thick could produce irrelevant spectroscopic results and cause erroneous conclusions. The intergranular phases present a major technological consideration for practical applications. In this communication we report the identification of a Cu2O grain boundary phase which forms during the sintering of YBa2Cu3O7-x (1:2:3 compound).Samples are prepared using a mixture of Y2O3. CuO, and BaO2 powders dispersed in ethanol for complete mixing. The pellets pressed at 20,000 psi are heated to 950°C at a rate of 5°C per min, held for 1 hr, and cooled at 1°C per min to room temperature. The samples show a Tc of 91K with a transition width of 2K. In order to prevent damage, a low temperature stage is used in milling to prepare thin foils which are then observed, using a liquid nitrogen holder, in a Philips 430T at 300 kV.

scholarly journals Synthesis and characterization of a new ZIF-67@MgAl2O4 nanocomposite and its adsorption behaviour

RSC Advances ◽  
2021 ◽  
Vol 11 (22) ◽  
pp. 13245-13255
Author(s):  
Mehdi Davoodi ◽  
Fatemeh Davar ◽  
Mohammad R. Rezayat ◽  
Mohammad T. Jafari ◽  
Mehdi Bazarganipour ◽  
...  
Keyword(s):  
Room Temperature ◽  
Magnesium Aluminate ◽  
Synthesis And Characterization ◽  
Magnesium Aluminate Spinel ◽  
Adsorption Behaviour ◽  
Zeolitic Imidazolate Framework ◽  
Simple Method

New nanocomposite of zeolitic imidazolate framework-67@magnesium aluminate spinel (ZIF-67@MgAl2O4) has been fabricated by a simple method at room temperature with different weight ratios.

scholarly journals Resonance and antiresonance in Raman scattering in GaSe and InSe crystals

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. Osiekowicz ◽  
D. Staszczuk ◽  
K. Olkowska-Pucko ◽  
Ł. Kipczak ◽  
M. Grzeszczyk ◽  
...  
Keyword(s):  
Raman Scattering ◽  
Temperature Effect ◽  
Band Gap ◽  
Raman Spectra ◽  
Quantum Interference ◽  
Optical Band Gap ◽  
Phonon Coupling ◽  
Phonon Modes ◽  
Electron Phonon Coupling ◽  
Resonant Raman

AbstractThe temperature effect on the Raman scattering efficiency is investigated in $$\varepsilon$$ ε -GaSe and $$\gamma$$ γ -InSe crystals. We found that varying the temperature over a broad range from 5 to 350 K permits to achieve both the resonant conditions and the antiresonance behaviour in Raman scattering of the studied materials. The resonant conditions of Raman scattering are observed at about 270 K under the 1.96 eV excitation for GaSe due to the energy proximity of the optical band gap. In the case of InSe, the resonant Raman spectra are apparent at about 50 and 270 K under correspondingly the 2.41 eV and 2.54 eV excitations as a result of the energy proximity of the so-called B transition. Interestingly, the observed resonances for both materials are followed by an antiresonance behaviour noticeable at higher temperatures than the detected resonances. The significant variations of phonon-modes intensities can be explained in terms of electron-phonon coupling and quantum interference of contributions from different points of the Brillouin zone.

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