scholarly journals A Novel Approach to Synthesis of FePt Magnetic Nanoparticles

2008 ◽  
Vol 1 ◽  
pp. 23-30 ◽  
Author(s):  
Kevin E. Elkins ◽  
Girija S. Chaubey ◽  
Vikas Nandwana ◽  
J.Ping Liu
Keyword(s):  
Oleic Acid ◽  
Magnetic Nanoparticles ◽  
Chemical Reduction ◽  
Reducing Agent ◽  
Fept Nanoparticles ◽  
Novel Approach ◽  
Economic Method

Chemical reduction of ferric acetylacetonate (Fe(acac)3) and platinum acetylacetonate (Pt(acac)2) using polyol as a reducing agent as well as an effective surfactant, has successfully yielded monodisperse FePt nanoparticles with a size of approximately 2 nm. When annealed samples were compared to FePt nanoparticles synthesized using oleic acid and oleylamine as the surfactants under identical conditions, nearly 30% increase in coercivity (Hc) was achieved with the new, simple and economic method.

scholarly journals Critical review on the chemical reduction of nitroaniline

RSC Advances ◽  
2020 ◽  
Vol 10 (32) ◽  
pp. 19041-19058 ◽  
Author(s):  
Muhammad Imran Din ◽  
Rida Khalid ◽  
Zaib Hussain ◽  
Jawayria Najeeb ◽  
Ahsan Sahrif ◽  
...  
Keyword(s):  
Critical Review ◽  
Catalytic Reduction ◽  
Chemical Reduction ◽  
Reducing Agent

Schematic illustration of catalytic reduction of 4-NA in the presence of nanocatalysts and a reducing agent.

Water-Dispersible FePt Nanoparticles Having ω-Mercapto-α-carboxylic Acid Ligands

2004 ◽  
Vol 853 ◽  
Author(s):  
Janis K. Mabry ◽  
Laura Beth Tackett ◽  
Hitesh Bargaria ◽  
Xiangcheng Sun ◽  
Earl T. Ada ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Ammonium Hydroxide ◽  
Photoelectron Spectra ◽  
Fept Nanoparticles ◽  
X Ray ◽  
Water Dispersible ◽  
Ordered Arrays ◽  
Oleyl Amine ◽  
Counter Ions ◽  
Thiol Ligand

ABSTRACTFePt nanoparticles, ∼ 2nm in diameter, were prepared by the polyol reduction of platinum(II) acetylacetonate and iron(III) acetylacetonate in the presence of oleyl amine and oleic acid surfactants. The particles were dispersed in hexane and the dispersion added to a solution of 11-mercaptoundecanoic acid in cyclohexanone. As the 11-mercaptoundecanoic acid ligands replaced the oleic acid ligands, the particles precipitated. The particles could be dispersed in basic water, made basic either with sodium hydroxide or ammonium hydroxide. X-ray photoelectron spectra showed a peak near 164 eV, sulfur (2p) confirming the presence of the thiol ligand. Similarly, the oleic acid ligands were replaced with either 3-mercaptopropionic acid or 16-mercaptohexadecanoic acid to give FePt particles that could be dispersed in water. Dispersions made with FePt nanoparticles having 11-mercaptoundeacnoic acid ligands and ammonium counter ions were dried on TEM grids to give highly ordered films consisting of close-packed arrays of FePt nanoparticles. When the counter ion was sodium, the particles tended to aggregate, instead of forming ordered arrays.

scholarly journals Green Synthesis of Novel Jasmine Bud-Shaped Copper Nanoparticles

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Malathi Sampath ◽  
Ramya Vijayan ◽  
Ezhilarasu Tamilarasu ◽  
Abiraman Tamilselvan ◽  
Balasubramanian Sengottuvelan
Keyword(s):  
Copper Nanoparticles ◽  
Isonicotinic Acid ◽  
Chemical Reduction ◽  
Average Particle Size ◽  
Acid Hydrazide ◽  
Reducing Agent ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Atomic Force ◽  
Transmission Electron

Novel jasmine bud-shaped copper nanoparticles were synthesized by a green chemical reduction method using polyvinylpyrrolidone (PVP) as a capping agent, L-ascorbic acid (AA) as a reducing agent as well as antioxidant agent, isonicotinic acid hydrazide (INH) as a reducing agent, and water as a solvent at 60–70°C (pH-7) in the presence of air. The UV-Vis absorption maximum obtained is 573 nm. The crystal lattice (fcc) structure of Cu Nps was confirmed by X-ray diffraction (XRD). The novel jasmine bud shape was visualized in a transmission electron microscope (TEM). The height of single copper nanobud was 6.41 nm as measured by atomic force microscope (AFM). The average particle size 6.95 nm is obtained by XRD results. Antibacterial activity of the Cu nanobuds was evaluated by testing against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria.

BIREFRINGENCE AND MAGNETO-OPTICAL PROPERTIES IN OLEIC ACID COATED Fe3O4 NANOPARTICLES: APPLICATION FOR OPTICAL SWITCH

2011 ◽  
Vol 10 (03) ◽  
pp. 515-520 ◽  
Author(s):  
SI-HUA XIA ◽  
JUN WANG ◽  
ZHANG-XIAN LU ◽  
FEIYAN ZHANG
Keyword(s):  
Magnetic Field ◽  
Optical Properties ◽  
Oleic Acid ◽  
Magnetic Nanoparticles ◽  
Magnetic Nanoparticle ◽  
Optical Switch ◽  
Colloidal Suspension ◽  
Experimental Parameters ◽  
Nanoparticle Chains ◽  
The Magnetic Field

We report magneto-optical properties in a kerosene colloidal suspension of oleic acid coated Fe3O4 nanoparticles (~14 nm). The magnetic colloids (fluids) show birefringence under a magnetic field. Systematical studies of the on–off switch times upon application of the on–off magnetic field with varied experimental parameters indicate that the switch response time depends strongly on the strength of the magnetic field and the concentration of the magnetic nanoparticles in the fluid. The data can be explained in terms of the formation of magnetic nanoparticle chains under a magnetic field. The important magneto-optical properties of the magnetic fluids allow us to design a tunable optical switch.

Iron oxide/oleic acid magnetic nanoparticles possessing biologically active choline derivatives

2018 ◽  
pp. 279-316 ◽  
Author(s):  
Alla Zablotskaya ◽  
Izolda Segal ◽  
Mikhail Maiorov ◽  
Dmitry Zablotsky ◽  
Elmars Blums
Keyword(s):  
Oleic Acid ◽  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Biologically Active

scholarly journals Indirect magnetic force microscopy

2019 ◽  
Vol 1 (6) ◽  
pp. 2348-2355 ◽  
Author(s):  
Joshua Sifford ◽  
Kevin J. Walsh ◽  
Sheng Tong ◽  
Gang Bao ◽  
Gunjan Agarwal
Keyword(s):  
Magnetic Nanoparticles ◽  
Magnetic Force Microscopy ◽  
Magnetic Force ◽  
Label Free ◽  
Force Microscopy ◽  
Novel Approach

Indirect magnetic force microscopy (ID-MFM): a novel approach to detect magnetic nanoparticles in a multimodal, label-free manner.

Effects of Substrates on the Self-Assembling of FePt Nanocrystals

2001 ◽  
Vol 674 ◽  
Author(s):  
Min Chen ◽  
David E. Nikles
Keyword(s):  
Chemical Reduction ◽  
Average Diameter ◽  
Iron Pentacarbonyl ◽  
Fept Nanoparticles ◽  
Hexagonal Close Packed ◽  
Self Assembling ◽  
Hydrocarbon Solvents ◽  
Carbon Coated ◽  
Self Assembled ◽  
Hexagonal Arrays

ABSTRACTFe48Pt52 nanoparticles were synthesized by the simultaneous chemical reduction of platinum acetylacetonate and thermal decomposition of iron pentacarbonyl. As-prepared the particles were spherical with an average diameter of 3 nm and a polydispersity of less than 5%. The particles were superparamagnetic and had a fcc structure. Highly ordered self-assembled supercrystals of particles were formed in TEM grids by deposition from dispersions in hydrocarbon solvents. Nanoparticles deposited on amorphous carbon-coated and SiO2-coated Cu grids tend to assemble into small domains of hexagonal arrays. Larger domains of hexagonal arrays formed on Si3N4 membrane TEM grids. For thin multilayers, the FePt nanoparticles tends to assemble into hexagonal close-packed lattices (ABABAB stacking). For the thicker multilayers, ABCABC stacking was observed. Small angle X-ray reflectivity of the particles on a Si (100) substrate show highly ordered multiplanar structure with d-spacing of 6.2 nm. The coercivity of self-assembled FePt films strongly depended on the annealing temperature. After annealing at 700°C for 30 minutes, the particles transformed from FCC to “FCT” phase and the coercivity of film increased up to 11570 Oe. However, the particle size increased to 16 nm due to sintering.

Shape-Controlled Synthesis and Formation Mechanism of Cobalt Nanopowders by a PVP-Assisted Method

2010 ◽  
Vol 654-656 ◽  
pp. 1186-1189 ◽  
Author(s):  
Bing Cong Zhang ◽  
Hong Ying Yu ◽  
Dong Bai Sun
Keyword(s):  
Hydrazine Hydrate ◽  
Chemical Reduction ◽  
Reducing Agent ◽  
Soft Template ◽  
Basic Solution ◽  
X Ray Diffraction ◽  
Mechanism Of Formation ◽  
X Ray ◽  
Nucleation Sites ◽  
Shape Controlled

Three different kinds of morphologies including spherical, chainlike and wirelike cobalt nanopowders, have been synthesized by chemical reduction of coblat chloride solution with hydrazine hydrate in basic solution. The products were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). It was revealed that the morphologies of the nanopowders depend on the concentration of Co2+ and the way of adding reducing agent (hydrazine hydrate). These two features affected the nucleation sites and the number of nucleuses. When the concentration of Co2+ was low, nucleuses formed in the soft template, while the reducing of the reducing agent added drop wise, a little number of nucleuses was formed. Based on that, a mechanism of formation, as a basis of gram-scale syntheses, was proposed.

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