Structure and magnetism of Fe–Co alloy nanoparticles

Klencsár, Z.; Németh, Péter; Zoltán, Sándor; Horváth, Tibor; Sajó, István E.; Mészáros, S.; Mantilla, J.; Coaquira, J. A. H.; Garg, V. K.; Кузманн, Э.; Tolnai, Gyula

doi:10.1016/j.jallcom.2016.03.068

Cited by 31 publications

(10 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The STEM-EDX profiles in Figure 2e,f show that the Fe/Co ratio in the shell is similar to the core. The (Fe x Co 1-x ) 3 O 4 peaks decrease in intensity with increasing Co content, indicating a higher oxidation resistance, as already reported for nearly equimolar Fe-Co nanoalloys [28].…”

Section: Structure Morphology and Composition Of Fe-co Nanoalloyssupporting

confidence: 80%

CO2 Hydrogenation over Unsupported Fe-Co Nanoalloy Catalysts

et al. 2020

View full text Add to dashboard Cite

The thermo-catalytic synthesis of hydrocarbons from CO2 and H2 is of great interest for the conversion of CO2 into valuable chemicals and fuels. In this work, we aim to contribute to the fundamental understanding of the effect of alloying on the reaction yield and selectivity to a specific product. For this purpose, Fe-Co alloy nanoparticles (nanoalloys) with 30, 50 and 76 wt% Co content are synthesized via the Inert Gas Condensation method. The nanoalloys show a uniform composition and a size distribution between 10 and 25 nm, determined by means of X-ray diffraction and electron microscopy. The catalytic activity for CO2 hydrogenation is investigated in a plug flow reactor coupled with a mass spectrometer, carrying out the reaction as a function of temperature (393–823 K) at ambient pressure. The Fe-Co nanoalloys prove to be more active and more selective to CO than elemental Fe and Co nanoparticles prepared by the same method. Furthermore, the Fe-Co nanoalloys catalyze the formation of C2-C5 hydrocarbon products, while Co and Fe nanoparticles yield only CH4 and CO, respectively. We explain this synergistic effect by the simultaneous variation in CO2 binding energy and decomposition barrier as the Fe/Co ratio in the nanoalloy changes. With increasing Fe content, increased activation temperatures for the formation of CH4 (from 440 K to 560 K) and C2-C5 hydrocarbons (from 460 K to 560 K) are observed.

show abstract

Section: Structure Morphology and Composition Of Fe-co Nanoalloyssupporting

confidence: 80%

CO2 Hydrogenation over Unsupported Fe-Co Nanoalloy Catalysts

et al. 2020

View full text Add to dashboard Cite

show abstract

“…As is known, the magnetic and mechanical properties of FeCo alloys are greatly affected by their Fe/Co ratios and microstructure [22]. Our previous study has shown that high magnetization saturation (215 A·m 2 ·kg −1 ) and low coercivity (73.4 Oe) can be obtained in the chemically synthesized Fe 65 Co 35 micro-sized particles [23].…”

Section: Introductionmentioning

confidence: 99%

Chemical Synthesis of High-Stable Amorphous FeCo Nanoalloys with Good Magnetic Properties

Yang

et al. 2018

Nanomaterials

View full text Add to dashboard Cite

It is difficult to fabricate high-purity amorphous FeCo alloys by traditional physical methods due to their weak glass forming ability. In this work, the fully amorphous FeCo nanoalloys with high purity and good stability have been prepared by a direct chemical reduction of Fe2+ and Co2+ ions with NaBH4 as the reducing agent and polyvinylpyrrolidone (PVP) as the surfactant. The morphologies, surface compositions and particle sizes with their distribution of these amorphous samples can be effectively tuned by the suitable PVP additions. High crystallization temperature up to 468 °C, high saturation magnetization of 196.2 A·m2·kg−1 and low coercivity of 83.3 Oe are obtained in amorphous FeCo nanoalloys due to their uniform distribution, weak surface oxidation and low surface B concentration. Good frequency-dependent magnetic properties can be also achieved in the fully compacted amorphous sample with a high density of 7.20 g/cm3. The simple chemical method, high stability and good magnetic properties for these amorphous FeCo nanoalloys promise their significant potential applications in high-power magnetic devices.

show abstract

“…MWCNTs filled with magnetic Co-containing nanoparticles have been proved to be useful for multiple innovations in nanotechnology [1][2][3], Li/air batteries [4][5][6][7][8], magnetic-storage devices [9], magnetic composites for drug delivery [10,11], catalysts for different processes [12][13][14][15][16][17][18], as well as absorption and microwave irradiation shielding material [19][20][21][22][23][24][25][26][27][28][29][30]. It is generally accepted that the magnetic properties of nanoparticles are determined by many factors, such as chemical composition [20,[31][32][33][34][35], crystallinity [36,37], size [37][38][39][40][41] and shape [35,[42][43]...…”

Section: Introductionmentioning

confidence: 99%

Co metal nanoparticles deposition inside or outside multi-walled carbon nanotubes via facile support pretreatment

Kazakova

Andreev

Selyutin

et al. 2018

Applied Surface Science

View full text Add to dashboard Cite

Decoration of one-dimensional multi-walled carbon nanotubes (MWCNTs) with zerodimensional Co nanoparticles leads to hybrid structures with chemical and electromagnetic features that are not available to the individual components. This work addresses the influence of the nature and structure of MWCNTs on the localization of Co nanoparticles. Depending on synthesis conditions, Co can be deposited on the external or in inner surfaces of the nanotubes. Co/MWCNTs hybrids have been characterized by in situ X-ray powder diffraction, highresolution transmission electron microscopy and 59 Co internal field nuclear magnetic resonance. It has been shown that the average diameter (7.2, 9.4 and 18.6 nm), number of walls (5-7, 12-15, 15-20), and functional composition of the MWCNTs have a remarkable effect on the size of Co nanoparticles and their distribution in the structure of MWCNTs. The observed phenomenon has 2 been rationalized in terms of nanotubes surface properties. Parent MWCNTs being hydrophobic and having limited porosity do not stabilize Co nanoparticles and, therefore, they are localized on the outside surface with relatively large average size and broad size distribution. On the other hand, the oxidation of the MWCNTs resulted in the penetration of Co nanoparticles inside of the nanotubes, presumably because of pore opening as well as increased hydrophilicity of the nanotubes.

show abstract

Structure and magnetism of Fe–Co alloy nanoparticles

Cited by 31 publications

References 55 publications

CO2 Hydrogenation over Unsupported Fe-Co Nanoalloy Catalysts

CO2 Hydrogenation over Unsupported Fe-Co Nanoalloy Catalysts

Chemical Synthesis of High-Stable Amorphous FeCo Nanoalloys with Good Magnetic Properties

Co metal nanoparticles deposition inside or outside multi-walled carbon nanotubes via facile support pretreatment

Contact Info

Product

Resources

About