scholarly journals Novel Cubic Magnetite Nanoparticle Synthesis Using Room Temperature Ionic Liquid

2012 ◽  
Vol 9 (3) ◽  
pp. 1070-1076 ◽  
Author(s):  
M. Sundrarajan ◽  
M. Ramalakshmi
Keyword(s):  
Electron Microscopy ◽  
Ionic Liquid ◽  
Iron Oxide ◽  
Magnetite Nanoparticles ◽  
Room Temperature ◽  
Average Particle Size ◽  
Precipitation Method ◽  
Average Particle ◽  
Face Centered Cubic ◽  
Ft Ir

Room Temperature Ionic liquids are relatively more useful in the synthesis of inorganic nanostructured materials because of their unique properties. To synthesize the iron oxide nanoparticle in simple precipitation method, a novel ionic liquid was used as the greener medium and stabilizing agent namely “1-n-butyl-3-methylimidazolium trifluoromethane sulfonate [BMIM][TfO]”. The crystallinity, chemical structure, morphology and magnetic properties of the synthesized magnetite nanoparticles have been characterized by using X-ray diffraction (XRD), Fourier Transform Infrared (FT-IR), Scanning electron microscopy (SEM), Atomic force microscopy(AFM), Transmission electron microscopy (TEM) and Vibrating sample magnetometer (VSM) studies. The XRD study is divulge that the synthesized magnetite nanoparticles have inverse spinel face centered cubic structure. The FT-IR vibration peaks show the formation of Fe3O4nanoparticles, where the vibration peak for Fe-O is deliberately presence at 584 cm-1. The average particle size of the synthesized nanoparticles is found to be 35 nm. Homogeneously dispersed cubic shape with superstructure is found through SEM, AFM and TEM examination studies. The synthesized iron oxide nanoparticles have a high saturation magnetization value of 25 emu/g, which is very much useful for biomedical applications.

Evaluation of the Antimicrobial Activity of Citric Acid Functionalized Magnetite Nanoparticles

2020 ◽  
Vol EJMM29 (4) ◽  
pp. 143-149
Author(s):  
Ahmed M. El-Khawaga ◽  
Ayman A. Farrag ◽  
Ahmed I. El-Batal ◽  
Mohamed A. Elsayed
Keyword(s):  
Antimicrobial Activity ◽  
Citric Acid ◽  
Magnetite Nanoparticles ◽  
Pathogenic Bacteria ◽  
Average Particle Size ◽  
Maximum Activity ◽  
Precipitation Method ◽  
Average Particle ◽  
Effective Prevention ◽  
Fe3o4 Nps

Background: Antimicrobial resistance (AMR) has emerged as one of the principal public health problems of the 21st century that threatens the effective prevention and treatment of an ever-increasing range of infections caused by bacteria no longer susceptible to the common medicines used to treat them. Objectives: To development of Fe3O4 NPs with specific sizes and shapes Potential as a new antibacterial agent. Methodology: In this study magnetite nanoparticles (Fe3O4 NPs) were synthesized through an aqueous co-precipitation method and functionalized with citric acid for outstanding their antimicrobial potential. Fe3O4 NPs were characterized by XRD, TEM, SEM, EDX and FTIR to analyze crystallinity, average particle size, morphology and functional groups, respectively. Antimicrobial activity was investigated against pathogenic bacteria as zone of inhibition (ZOI) and minimum inhibitory concentration (MIC). Results: Antimicrobial results showed that CA- Fe3O4 NPs owns maximum activity against Staphylococcus aureus and E. coli by 18.0 and 15.0mm ZOI, respectively. Conclusion: It should be noted that (CA-Fe3O4) NPs are also active upon Gram-positive than Gram- negative bacteria. The synthesized (CA-Fe3O4) NPs are promising for potential applications as antimicrobial agent and in drug delivery fields.

Biosynthesis and Characterization of Copper Nanoparticles Using a Bioflocculant Extracted from Alcaligenis faecalis HCB2

2019 ◽  
Vol 11 (11) ◽  
pp. 1064-1070 ◽  
Author(s):  
Nkosinathi G. Dlamini ◽  
Albertus K. Basson ◽  
V. S. R. Rajasekhar Pullabhotla
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Copper Nanoparticles ◽  
Average Particle Size ◽  
Thermo Gravimetric Analysis ◽  
Average Particle ◽  
Gravimetric Analysis ◽  
X Ray ◽  
Transmission Electron ◽  
Ft Ir

Bioflocculant from Alcaligenis faecalis HCB2 was used in the eco-friendly synthesis of the copper nanoparticles. Nanoparticles were characterized using a scanning electron microscope (SEM), transmission electron microscopy (TEM), UV-visible spectroscopy, thermo gravimetric analysis (TGA) and Fourier Transform Infrared Spectroscopy (FT-IR). The transmission electron microscopy images showed close to spherical shapes with an average particle size of ∼53 nm. Energy-dispersive X-ray spectroscopy analysis confirmed the presence of the Cu nanopartilces and also the other elements such as O, C, P, Ca, Cl, Na, K, Mg, and S originated from the bioflocculant. FT-IR results showed the presence of the –OH and –NH2 groups, aliphatic bonds, amide and Cu–O bonds. Powder X-ray diffraction peaks confirmed the presence of (111) and (220) planes of fcc structure at 2 of 33° and 47° respectively with no other impurity peaks.

DIELECTRIC PROPERTIES OF ULTRAFINE Zn-DOPED CaCu3Ti4O12 CERAMIC

2012 ◽  
Vol 02 (01) ◽  
pp. 1250007 ◽  
Author(s):  
LAXMAN SINGH ◽  
U. S. RAI ◽  
K. D. MANDAL ◽  
MADHU YASHPAL
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Room Temperature ◽  
Single Phase ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Sintered Powder

Ultrafine powder of CaCu2.80Zn0.20Ti4O12 ceramic was prepared using a novel semi-wet method. DTA/TG analysis of dry powder gives pre-information about formation of final product around 800°C. The formation of single phase was confirmed by X-ray diffraction analysis. The average particle size of sintered powder of the ceramic obtained from XRD and Transmission electron microscopy was found 59 nm and 102 nm, respectively. Energy Dispersive X-ray studies confirm the stoichiometry of the synthesized ceramic. Dielectric constant of the ceramic was found to be 2617 at room temperature at 1 kHz.

Structural, Optical and Magnetic Properties of Ni Doped ZnS Nanoparticles

2018 ◽  
Vol 24 (8) ◽  
pp. 5640-5644
Author(s):  
B Sreenivasulu ◽  
S. Venkatramana Reddy ◽  
P. Venkateswara Reddy
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Absorption Spectra ◽  
Spherical Surface ◽  
Room Temperature Ferromagnetism ◽  
Average Particle Size ◽  
Precipitation Method ◽  
Chemical Compositions ◽  
Average Particle ◽  
X Ray

Pure ZnS and 3 mol% of Ni doped ZnS nano powders are prepared by chemical co-precipitation method. Properties of ZnS: Ni2+ nanoparticles are studied by X-ray diffraction Spectra (XRD), Raman spectroscopy (RS), Photoluminescence (PL), Absorption Spectra, Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDAX), Transmission electron microscopy (TEM) and Vibrating sample magnetometer (VSM). From XRD data, it conform the structure of ZnS, and particle size of pure and Ni doped ZnS data indicates the incorporation of Ni2+ in ZnS nanocrystal lattice. Raman spectra for pure and Ni doped samples exhibited vibrational modes confirm the structure of ZnS. Photoluminescence spectra reveal that the emission peaks are in UV and visible regions; this is confirming the absorption spectra. SEM micrographs show spherical morphology, and chemical compositions of samples are in stoichiometric proportions. TEM micro graphs show the spherical surface morphology and average particle size for pure and Ni2+ doped nanoparticles are in the range of 2–3 nm, this is good agreement with XRD results. M–H curves from VSM show room temperature ferromagnetism.

Fabrication and Characterization of YAG Nanopowders by Co-Precipitation under Ultrasonic Radiation

2011 ◽  
Vol 284-286 ◽  
pp. 839-843 ◽  
Author(s):  
Li Li Wang ◽  
Jin Chen ◽  
Guang Cheng Yang ◽  
Fu De Nie
Keyword(s):  
Average Particle Size ◽  
Precipitation Method ◽  
Average Particle ◽  
Synthetic Process ◽  
Ultrasonic Radiation ◽  
Ft Ir ◽  
Fabrication And Characterization ◽  
Co Precipitation ◽  
Carbonate Precursor

A carbonate precursor with high sintering activity was prepared by co-precipitation method under ultrasonic radiation. This precursor precipitant completely transformed to pure YAG phase after being calcined at 900 °C for 4 h. The properties of YAG nanopowders obtained under different synthetic process were studied by XRD, TG-DSC, FT-IR and SEM. The results show that the ultrasonic radiation can fine the precursor and reduce its agglomeration. YAG nanopowders with an average particle size of about 60 nm were obtained and particles were sphere-shaped with good dispersity.

Polyoxometalate and copolymer-functionalized ionic liquid catalyst for esterification

2011 ◽  
Vol 84 (3) ◽  
pp. 541-551 ◽  
Author(s):  
Huan Li ◽  
Jizhong Chen ◽  
Li Hua ◽  
Yunxiang Qiao ◽  
Yinyin Yu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ionic Liquid ◽  
Fourier Transform ◽  
Room Temperature ◽  
Homogeneous Solution ◽  
Imidazolium Cation ◽  
Transmission Electron ◽  
Ft Ir ◽  
Halogen Free

A new room-temperature ionic liquid (RTIL) consisting of a polyoxometalate (POM) anion and tri-block copolymer (P123)-functionalized imidazolium cation was synthesized and utilized as a halogen-free catalyst for esterification. The catalytic system was a homogeneous solution at the beginning of the reaction, but an emulsion formed during the course of the reaction, and a progressive phase separation of the catalyst occurred at 0 °C over the course of 3 h. Dynamic light scattering (DLS), transmission electron microscopy (TEM), and Fourier transform/infrared spectroscopy (FT/IR) have been used to characterize the properties of the IL during the reaction. The new IL catalyst was found to be highly efficient in the esterification of various alcohols and can be recycled at least seven times.

scholarly journals Variation of Alkali Concentration and Temperature: Its Effect on the Morphology of ZnO Nanoparticles Synthesized via Solvothermal Technique

2021 ◽  
Vol 411 ◽  
pp. 3-15
Author(s):  
Boon Siong Wee ◽  
Eric Kwabena Droepenu ◽  
Suk Fun Chin ◽  
Kuan Ying Kok ◽  
Woei Ting
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Average Particle Size ◽  
Alkali Concentration ◽  
Average Particle ◽  
Zno Nanostructures ◽  
Tem Analysis ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Concentration Ratios

This study reports on synthesis of ZnO nanostructures using Zinc chloride (ZnCl2) as precursors and Potassium hydroxide (KOH) as alkaline source in a solvothermal process with varying molar concentrations (Zn2+/OH-) of 1:1, 1:3 and 1:5 for temperatures of 30 °C and 50 °C. The synthesized nanostructures were characterized by X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FT-IR) Spectroscopy, and Ultraviolet Visible (UV-Vis) spectroscopy. ZnO nanostructures synthesized at lower ratios (1:1) exhibited wurtzite hexagonal shapes. However, as the concentration ratios increases in both cases, spherical structures were formed with the emergence of some rod-like structures dominating, and finally aggregated to form flower-like structures at 30 °C temperature. The average crystallite size for nanostructures from XRD (30-50 °C) were in the range 15-21 nm whereas the average particle size from TEM analysis (30-50 °C) were in the range 39-76 nm. Increase in temperature and molar concentration of the alkaline source generally decreased the crystallite and particle size of the as well as a decrease in the wavelength of ZnO nanostructures as a result of blue-shifting of the absorption peak. FT-IR spectra of ZnO NSs prepared from concentration ratios of Zn2+: OH- (1:1, 1:3 and 1:5) at 30 °C and 50 °C showed characteristic peak bands at 461-467 cm-1 and 460-462 cm-1 respectively.

scholarly journals Study of structural, morphological, optical and electroluminescent properties of undoped ZnO nanorods grown by a simple chemical precipitation

2015 ◽  
Vol 33 (4) ◽  
pp. 751-759 ◽  
Author(s):  
A. Singh ◽  
H.L. Vishwakarma
Keyword(s):  
Crystallite Size ◽  
Threshold Voltage ◽  
Room Temperature ◽  
Zno Nanorods ◽  
Average Particle Size ◽  
Chemical Precipitation ◽  
Absorption Peak ◽  
Precipitation Method ◽  
Average Particle ◽  
Simple Chemical

AbstractIn this work, zinc oxide (ZnO) nanorods were obtained by a simple chemical precipitation method in the presence of capping agent: polyvinyl pyrrolidone (PVP) at room temperature. X-ray diffraction (XRD) result indicates that the synthesized undoped ZnO nanorods have hexagonal wurtzite structure without any impurities. It has been observed that the growth direction of the prepared ZnO nanorods is [1 0 1]. XRD analysis revealed that the nanorods have the crystallite size of 49 nm. Crystallite size is calculated by Debye-Scherrer formula and lattice strain is calculated by Williomson-Hall equation. Cell volume, Lorentz factor, Lorentz polarization factor, bond length, texture coefficient, lattice constants and dislocation density have also been studied. We also compared the interplanar spacings and relative peak intensities with their standard values at different angles. The scanning electron microscope (SEM) images confirmed the size and shape of these nanorods. It has been found that the diameter of the nanorods ranges from 1.52 μm to 1.61 μm and the length is about 4.89 μm. It has also been observed that at room temperature ultraviolet visible (UV-Vis) absorption band is around 355 nm (blue shifted as compared to the bulk). The average particle size has also been calculated by mathematical model of effective mass approximation equation, using UV-Vis absorption peak. Finally, the bandgap has been calculated using UV-absorption peak. Electroluminescence (EL) studies show that emission of light is possible at very small threshold voltage and it increases rapidly with increasing applied voltage. It is seen that smaller ZnO nanoparticles give higher electroluminescence brightness starting at lower threshold voltage. The brightness is also affected by increasing the frequency of AC signal.

A New Method for Direct Determination of the Recoilless Fraction with Application to Magnetic Nanoparticles

2002 ◽  
Vol 721 ◽  
Author(s):  
Monica Sorescu
Keyword(s):  
Room Temperature ◽  
Average Particle Size ◽  
Direct Determination ◽  
Average Particle ◽  
Lattice Method ◽  
Recoilless Fraction ◽  
Single Room ◽  
Magnetite Particles ◽  
Physical Mixtures

AbstractWe propose a two-lattice method for direct determination of the recoilless fraction using a single room-temperature transmission Mössbauer measurement. The method is first demonstrated for the case of iron and metallic glass two-foil system and is next generalized for the case of physical mixtures of two powders. We further apply this method to determine the recoilless fraction of hematite and magnetite particles. Finally, we provide direct measurement of the recoilless fraction in nanohematite and nanomagnetite with an average particle size of 19 nm.

Microstructure Characterization of Ag Nanoparticles Prepared by Hydrothermal Method

2012 ◽  
Vol 476-478 ◽  
pp. 1138-1141
Author(s):  
Zhi Qiang Wei ◽  
Qiang Wei ◽  
Li Gang Liu ◽  
Hua Yang ◽  
Xiao Juan Wu
Keyword(s):  
Crystal Structure ◽  
Particle Size ◽  
Hydrothermal Method ◽  
Ag Nanoparticles ◽  
Average Particle Size ◽  
Average Particle ◽  
Face Centered Cubic ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Face Centered

Ag nanoparticles were successfully synthesized by hydrothermal method under the polyol system combined with traces of sodium chloride, Silver nitrate(AgNO3) and polyvinylpyrrolidone (PVP) acted as the silver source and dispersant respectively. The samples by this process were characterized via X-ray powder diffraction (XRD), Brunauer–Emmett–Teller (BET) adsorption equation, transmission electron microscopy (TEM) and the corresponding selected area electron diffraction (SAED) to determine the chemical composition, particle size, crystal structure and morphology. The experiment results indicate that the crystal structure of the samples is face centered cubic (FCC) structure as same as the bulk materials, The specific surface area is 24 m2/g, the particle size distribution ranging from10 to 50 nm, with an average particle size about 26 nm obtained by TEM and confirmed by XRD and BET results.

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