Journal articles: 'Layer magnetic oxide'

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Sobreiro, H., B. Berini, N. Keller, and David S. Schmool. "Transport Properties in All Oxide Magnetic Multilayers." Materials Science Forum 587-588 (June 2008): 318–22. http://dx.doi.org/10.4028/www.scientific.net/msf.587-588.318.

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The all oxide magnetic multilayer system [LaNiO3/SmFeO3]n (for n = 1 and 2), grown on single crystal SrTiO3(100) substrates, has been produced using the laser MBE (Molecular Beam Epitaxy) technique. We have made a systematic study of the electrical transport properties in the temperature range from 15–300K. As part of this work, we have made a detailed study of the metallic properties of the LaNiO3 layer as a function of the oxygen partial pressure (pO2) and substrate temperature (TS). We have measured magnetic layers of SmFeO3 with LaNiO3 electrodes as a function of the magnetic layer thickness (10 – 470 nm). A non-metallic behaviour is observed with evidence of a “hopping” mechanism at low temperatures. For the n = 2 multilayers, we have measured the temperature dependence of resistance for the sample series with varying LaNiO3 interlayer thickness (t = 2 – 30 nm). We observe an appreciable increase of the low temperature resistance for the interlayer thicknesses between 3.75 – 7.5 nm. This could indicate a change in coupling from ferromagnetic to antiferromagnetic between the magnetic layers.

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Marinca, Traian Florin, Bogdan Viorel Neamțu, Florin Popa, Amalia Mesaroș, and Ionel Chicinaș. "Spark Plasma Sintered Soft Magnetic Composite Based on Fe-Si-Al Surface Oxidized Powders." Materials 15, no. 22 (November 8, 2022): 7875. http://dx.doi.org/10.3390/ma15227875.

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Soft magnetic composites (SMCs) need a stable matrix to apply heat treatments for enhancing their magnetic characteristics. A stable matrix can be offered by alumina, but the densification of the ferromagnetic particles covered by this oxide (by sintering) can be very difficult. This paper proposes a feasible synthesis route for obtaining alumina matrix SMCs. An Fe-Si-Al alloy with nominal composition Fe85Si9Al6 was obtained by mechanical alloying of elemental Fe, Si, and Al powders, and further, the as-milled powders were superficially oxidized by immersion in HCl solution. The oxide layer was composed of iron, silicon, and aluminum oxides, as the Fourier-transform infrared spectroscopy technique revealed. The Fe-Si-Al@oxide powder was densified by the spark plasma sintering technique—SPS. Upon sintering, a continuous matrix of oxide (mainly alumina) was formed by the reaction of the Fe-Si-Al powder coreswith their oxide layer. The main part of the composite compacts after sintering consisted of an Fe3Si-ordered phase dispersed in an oxide matrix. The DC and AC tests of magnetic composite compacts showed that upon increasing the sintering temperature, the density, magnetic induction, and magnetic permeability increased. The initial magnetic permeability was constant in the entire range of testing frequencies and the magnetic losses increased linearly. The stability of the magnetic characteristics in frequency is promising for developing further such types of magnetic composite.

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Zarzycki, Arkadiusz, Juliusz Chojenka, Marcin Perzanowski, and Marta Marszalek. "Electrical Transport and Magnetic Properties of Metal/Metal Oxide/Metal Junctions Based on Anodized Metal Oxides." Materials 14, no. 9 (May 4, 2021): 2390. http://dx.doi.org/10.3390/ma14092390.

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In this paper, we describe magnetoelectric properties of metal/metal-oxide/metal junctions based on anodized metal oxides. Specifically, we use Ti and Fe metallic layers separated by the porous metal-oxides of iron or titanium formed by the anodization method. Thus, we prepare double junctions with at least one ferromagnetic layer and measure magnetoresistance, as well as their current-voltage and magnetic characteristics. We find that magnetoresistance depends on that junction composition and discuss the nature of differential resistance calculated from I-V characteristics. Our findings show that a top metallic layer and the interface between this layer and anodized oxide, where strong interatomic diffusion is expected, have the strongest influence on this observed behavior.

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Mosiniewicz-Szablewska, Ewa, Antonia R. Clavijo, Ana P. O. R. Castilho, Leonardo G. Paterno, Marcelo A. Pereira-da-Silva, Jarosław Więckowski, Maria A. G. Soler, and Paulo C. Morais. "Magnetic studies of layer-by-layer assembled polyvinyl alcohol/iron oxide nanofilms." Physical Chemistry Chemical Physics 20, no. 41 (2018): 26696–709. http://dx.doi.org/10.1039/c8cp05404e.

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Peng, Yuan Dong, Jian Ma, Wen Jun Zhang, Chong Xi Bao, Jun Wu Nie, and Jian Ming Ruan. "Microstructure and Magnetic Properties of Fe-Si-Al Soft Magnetic Composite." Advanced Materials Research 683 (April 2013): 7–10. http://dx.doi.org/10.4028/www.scientific.net/amr.683.7.

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In this paper, the Fe-9Si-6Al soft magnetic composite has been prepared via powder particles coated with aluminum oxide and silicone. The magnetic properties and microstructure of Fe-Si-Al SMC has been investigated. Results showed that the powder particles surface contained a thin insulating layer made of aluminum oxide and silicone. After annealed at 800°C for 60min, the particles of component are all by themselves and the insulating layer is not destroyed. The Fe-Si-Al SMC has excellent magnetic properties. The magnetic permeability is steady with the frequency changing at 5kHz-100kHz range.

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Chojenka, Juliusz, Arkadiusz Zarzycki, Marcin Perzanowski, Michał Krupiński, Tamás Fodor, Kálmán Vad, and Marta Marszałek. "Tuning of the Titanium Oxide Surface to Control Magnetic Properties of Thin Iron Films." Materials 16, no. 1 (December 28, 2022): 289. http://dx.doi.org/10.3390/ma16010289.

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We describe the magnetic properties of thin iron films deposited on the nanoporous titanium oxide templates and analyze their dependance on nanopore radius. We then compare the results to a continuous iron film of the same thickness. Additionally, we investigate the evolution of the magnetic properties of these films after annealing. We demonstrate that the M(H) loops consist of two magnetic phases originating from the iron layer and iron oxides formed at the titanium oxide/iron interface. We perform deconvolution of hysteresis loops to extract information for each magnetic phase. Finally, we investigate the magnetic interactions between the phases and verify the presence of exchange coupling between them. We observe the altering of the magnetic properties by the nanopores as a magnetic hardening of the magnetic material. The ZFC-FC (Zero-field cooled/field cooled) measurements indicate the presence of a disordered glass state below 50 K, which can be explained by the formation of iron oxide at the titanium oxide-iron interface with a short-range magnetic order.

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Eckstein, J. N., I. Bozovic, and G. F. Virshup. "Atomic Layer-by-Layer Engineering of High Tc Materials and Heterostructure Devices." MRS Bulletin 19, no. 9 (September 1994): 44–50. http://dx.doi.org/10.1557/s0883769400047989.

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Oxides exhibit most of the interesting phenomena known to occur in solid-state systems. As a class of materials they may be richer in phenomenology than any other comparable class. Oxides can be insulators, semiconductors, or metals. The copperoxide-based compounds we have studied are superconductors with the highest critical temperatures. In some oxides, electrons manifest simple single-particle transport properties, with a high mobility; in others, they show strongly correlated behavior resulting in a Mott-Hubbard transition, localization, and charge- or spin-density waves. In some oxides, electron-phonon coupling leads to polaronic transport. Others show collective states such as magnetism; in some there are large local magnetic moments that can couple to form ferromagnetic or antiferromagnetic phases that exist up to high temperatures. Yet others have large nonlinear dielectric and optical properties. In fact, it would seem there is very little that some such oxide couldn't do for or to the experimenter.

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Sawada, K., H. Endo, M. Doi, N. Hasegawa, and M. Sahashi. "Magnetic Coupling of Spin Valves Including Nano-Structured Magnetic Oxide Layer." Journal of the Magnetics Society of Japan 32, no. 5 (2008): 509–14. http://dx.doi.org/10.3379/msjmag.32.509.

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Zhang, Huanxia, Wen Wu, Jie Zhou, Xinchao Zhang, Tantan Zhu, and Mingqiong Tong. "Magnetic field-induced self-assembly of chemically modified graphene oxide on cellulose fabrics for the fabrication of flexible conductive devices." Cellulose 28, no. 4 (January 6, 2021): 2303–14. http://dx.doi.org/10.1007/s10570-020-03653-1.

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AbstractIn this present study, we have successfully fabricated the cellulose fabric with excellent electrical conductivity by depositing the graphene oxide grafted with the modified ferroferric oxide (GOF) upon fabric substrate via layer-by-layer magnetic-field-induced self-assembly apporoach and followed by chemical reduction. The results indicated that the morphologies of graphene oxide nanosheets for three-layer deposited fabrics could form the highly oriented wrinkled structures, which resulted from the synergistic interactions of magnetic induction force on magnetic doublet, hydrogen bonds and van der Waals. The volume resistivity of the three-layer deposited fabric could reach to 64.8 Ω cm compared with that of pure RGO-coated viscose fabrics (137.94 Ω cm) in the previous work, which could be favorable for improving the electrical conductivity and decreasing the graphene oxide consumption. Furthermore, the three-layer deposited fabric possessed excellent washing durability even after twelve times water laundering. Our results suggested that the flexible GOF-coated fabric had great potential in conductive devices for wearable electronics, strain sensors, smart actuators and bioelectrodes and so on.

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Li, Ming, Shuanhu Wang, Yang Zhao, and Kexin Jin. "Review on fabrication methods of SrTiO3-based two dimensional conductive interfaces." European Physical Journal Applied Physics 93, no. 2 (February 2021): 21302. http://dx.doi.org/10.1051/epjap/2021200326.

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The SrTiO3-based two dimensional conductive interfaces have attracted considerable attention in the last decade owing to the emergence of novel physical phenomena. These heterointerfaces are generally formed by depositing the films on SrTiO3 substrates. Particularly, the controllable and precise characteristics of pulsed laser deposition (PLD) allow the deposition of an atomically flat oxide films and control the growth layer-by-layer. Recently, the deposition methods of atomic layer deposition (ALD) and spin coating have exhibited an excellent practicability and many interesting results are obtained by analyzing the chemical reaction pathway. In addition, the surface treatment methods (such as high vacuum annealing, Ar+ ion irradiation and photoirradiation etc.) can also obtain the two dimensional conductive SrTiO3 effectively. Furthermore, owing to the difference of fabrication method, the SrTiO3-based two dimensional conductive interfaces significantly show different performances of the same oxides. Thus, this review compares the characteristics of different methods in preparing the SrTiO3-based interfaces. The appropriate method and process is the precondition to obtain high-quality oxide films and establish the foundation for the development of oxide and interface electronics.

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11

Yunas, Jumril, Azrul Azlan Hamzah, and Majlis Burhanuddin Yeop. "Theoretical Analysis of Thin Film Oxide as Insulator of Planar Micro-Coils." Advanced Materials Research 194-196 (February 2011): 2462–66. http://dx.doi.org/10.4028/www.scientific.net/amr.194-196.2462.

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In this paper, a theoretical analysis of thin film oxide resulted from lumped element model analysis using ASITIC simulation tool is presented. The study is aimed to investigate the effect of the oxide thickness on the electrical characteristics of planar micro-coils. Some important device parameters, such as parasitic capacitances and resistances caused by oxide and substrate layer, and quality factor of the planar coil, as well as the characteristic of the magnetic field coupled between the coils are analyzed in wide range of operating frequency. The simulation results show that there is significant influence of the oxide thickness to the device characteristics. It is shown that by increasing the thickness of the oxide layer on the substrate, a high Q-factor of 5 can be obtained, while the magnetic coupling is improved when the thickness of the oxide layer residing between metal layers is reduced.

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Escalera-López, D., E. Gómez, and E. Vallés. "Electrochemical growth of CoNi and Pt–CoNi soft magnetic composites on an alkanethiol monolayer-modified ITO substrate." Physical Chemistry Chemical Physics 17, no. 25 (2015): 16575–86. http://dx.doi.org/10.1039/c5cp02291f.

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CoNi and Pt–CoNi magnetic layers on indium-tin oxide (ITO) substrates modified by an alkanethiol self-assembled monolayer (SAM) have been electrochemically obtained as an initial stage to prepare semiconducting layer-SAM-magnetic layer hybrid structures.

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13

Pérez Alcázar, Germán A., Ligia Edith Zamora, José Francisco Marco, Juan José Romero, Jesús María González, and Francisco Javier Palomares. "Magnetic and Structural Characterization of Mechanically Alloyed Fe50co50 Samples." Revista de Ciencias 15 (February 13, 2012): 41–47. http://dx.doi.org/10.25100/rc.v15i0.516.

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Samples of nominal composition Fe50Co50 were produced by mechanical alloying byusing a planetary ball mill and different milling times. The samples were studied via X-raydiffraction, Mössbauer spectroscopy, and X-ray photoelectron spectroscopy to characterize thephase distribution resulting from the milling process. The Mössbauer data indicated that Co startsdiffusing into Fe after 8 h of milling. Between t = 8h and t = 24 h the sample has a heterogeneouscomposition, presenting a bimodal hyperfine field distribution with maxima centred at 34.3 T and35.8 - 36.4 T, compatible with the presence of different Fe environments (richer in Co and richerin Fe, respectively). After 48 h of milling, the sample presents a more homogeneous compositionshowing an almost symmetric hyperfine magnetic field distribution centred at H=34.9 T,indicating that a disordered equiatomic FeCo solid solution has already been formed. The X-rayphotoelectron spectroscopy data indicate that the native oxide layer formed on the freshly milledsamples contains Co2+, Fe2+ and Fe3+ oxides. After complete removal of this native oxide layer byAr ion bombardment, X-ray photoelectron spectroscopy analysis yields the composition of thenominal equiatomic Fe50Co50 alloy.

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Su, Zhaowei, Rui Mu, Yonghui Cui, Hongda Zhu, Xuetian Li, and Zhongcai Shao. "Study on micro-arc oxidation coating of magnetic metal powder composite magnesium alloy." Anti-Corrosion Methods and Materials 67, no. 5 (August 28, 2020): 501–8. http://dx.doi.org/10.1108/acmm-03-2020-2269.

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Purpose The purpose of this paper is to prepare composite micro-arc oxide coatings with better wear resistance and corrosion resistance. Design/methodology/approach A nickel powder composite micro-arc oxide film was prepared on the surface of the magnesium alloy by the method of organically combining ultra-fine Ni powder with micro arc oxidation film layer. In this experiment, the changes in the corrosion resistance and microstructure of the composite film layer after adding Ni powder were studied, and the effect of the addition of glycerin on the corrosion resistance of the film layer was analyzed. Findings The results show that the ultra-fine nickel powder was successfully prepared by the liquid phase reduction method, and the micro-arc oxidation process was modified under the optimal addition amount. The surface of the micro-arc oxide film made of ultra-fine nickel powder was found by SEM to have smooth surfaces and few holes. According to X-ray diffraction analysis, the phase composition of the micro-arc oxide film layer was Mg, Ni, NiSiO4, MgNi (SiO4) and Mg2SiO4. According to the results of electrochemical tests, the corrosion resistance of the micro-arc oxidation composite film layer was improved after the addition of ultra-fine Ni powder, the corrosion current was greatly reduced and the impedance has been improved. And after adding glycerin, the surface of the film layer becomes denser, and the corrosion resistance of the micro-arc oxide film is significantly improved. Originality/value Through this experimental research, a micro-arc oxide coating of powder composite magnesium alloy was successfully prepared. The corrosion resistance of the micro-arc oxidation film layer has been improved, and certain functions had been given to the micro-arc oxidation composite film, which has increased the application field of magnesium alloys.

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Chen, Sui-Pin, Ching-Ray Chang, and Chih-Huang Lai. "Magnetoresistance in magnetic multilayers with the nano-oxide layer." Journal of Applied Physics 93, no. 10 (May 15, 2003): 7699–701. http://dx.doi.org/10.1063/1.1555772.

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Yoshida, Kazuki, Issei Nagata, Kentaro Saito, Masanori Miura, Kensaku Kanomata, Bashir Ahmmad, Shigeru Kubota, and Fumihiko Hirose. "Room-temperature atomic layer deposition of iron oxide using plasma excited humidified argon." Journal of Vacuum Science & Technology A 40, no. 2 (March 2022): 022408. http://dx.doi.org/10.1116/6.0001622.

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Room-temperature atomic layer deposition (RT-ALD) of iron oxide is developed with a precursor of bis(N, N′-diisopropyl-propionamidinate)iron [(DIPPA)2Fe] and plasma excited humidified Ar. Saturated conditions of (DIPPA)2Fe and plasma excited humidified Ar exposures at room temperature (23–25 °C) are investigated by in situ IR absorption spectroscopy for finding the RT-ALD process condition. Using the designated process, the growth per cycle of the iron oxide RT-ALD is confirmed as 0.15 nm/cycle based on the film thicknesses measured by the spectroscopic ellipsometer. The x-ray photoelectron spectroscopy suggests that the stoichiometry of the deposited iron oxide is closed to that of Fe2O3. The grown film is composed of partly crystallized iron oxides, confirmed by cross-sectional TEM and AFM. The RT deposited iron oxide exhibits a magnetic volume susceptibility of 1.52, which implies the applicability of the present coating for magnetic drug delivery. We discuss the surface reaction with the IR absorption spectroscopy and the quartz crystal microbalance. The (DIPPA)2Fe molecule is suggested to adsorb on the Fe2O3 surface with mixed first- and second-order reactions at RT. It is also suggested that amidinate ligands in (DIPPA)2Fe are released in the course of the adsorption and the remaining ligands are oxidized by the plasma excited humidified Ar. The RT iron oxide deposition is demonstrated, and the reaction mechanism of room-temperature ALD is discussed in this paper.

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Su, Jia Quan, and Yue Kuo. "Communication—Exploration of Plasma Oxidized Copper Oxide as a Copper Passivation Layer." ECS Journal of Solid State Science and Technology 11, no. 3 (March 1, 2022): 035005. http://dx.doi.org/10.1149/2162-8777/ac5be2.

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Passivation properties of the plasma oxidized copper oxide on the copper line have been studied using the electromigration stress method. The self-aligned copper oxide passivation layer has the unique property of gettering copper atoms diffused through it at the high temperature raised from the stress current induced Joule heating. On the other hand, the line broken time is shortened with the increase of the copper oxide passivation layer thickness. Therefore, for the passivation application, a thin copper oxide layer is better than a thick copper oxide layer.

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Yang, Xiu Pei, Zhi Jing Tan, Yu Li Fu, Gu Li, and Hua Xu. "Synthesis and Characterization of Au/Fe₃O₄ Nanocomposite." Advanced Materials Research 1082 (December 2014): 6–9. http://dx.doi.org/10.4028/www.scientific.net/amr.1082.6.

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A new kind of surface-functionalized magnetic nanoparticles was fabricated by surface modification of ferroferric oxide with monolayer-protected gold nanoparticles. Ferroferric oxide nanoparticles were firstly synthesized by co-precipitating Fe2+ and Fe3+ ions in base solution, and then coated with a layer of 3-aminopropyltriethoxysilane by silanization reaction. Gold nanoparticles were surface-attached with 2-mercapto-4-methyl-5-thiazoleacetic acid which were subsequently linked to the modified ferroferric oxide nanoparticles to produce Au/Fe3O4 composite materials. The outer layer of ligand (2-mercapto-4-methyl-5-thiazoleacetic acid) on Au/Fe3O4 can function as binding sites for drugs and biomolecules, whereas the innermost magnetic cores are able to respond to an externally applied magnetic field. The as-synthesized Au/Fe3O4 nanocomposite is superparamagnetic (31.4 emu/g), thus rendering it potentially applicable in magnetic drug delivery and bioseparation.

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Rahman, Md Ataur, Tajmeri SA Islam, and Md Mufazzal Hossain. "Optical, Magnetic and Adsorptive Properties of Prepared Copper(II) Oxide." Dhaka University Journal of Science 68, no. 1 (January 30, 2020): 7–12. http://dx.doi.org/10.3329/dujs.v68i1.54593.

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We report the surface morphology, structural propertiesand surface characterization of copper(II) oxide by scanning electron microscope, energy dispersive X-ray spectroscopy, Fourier transformation infrared spectroscopy, attenuated total reflection infrared spectroscopy and X-ray diffraction. All the data of analysis were consistent with each other and bear the evidence for the purity of the prepared oxide. Kubelka-Munk (K-M) theory is used for the determination of direct band gap of the prepared oxide from UV-visible reflectance spectrum. The band gap value of the bulk material was found to be 4.15 0.05 eV from F(R) versus energy and (F(R) hv)n versus energy plots, with n=1/2 and n=2 Molar magnetic susceptibility and effective magnetic moment of the oxide are 3.393×10-4(cgs) and 0.895 BM respectively which suggest that the oxide is paramagnetic. Catalytic activity was investigated by the study of adsorption of brilliant red (BR) on the surface of prepared oxide in aqueous medium at room temperature. Adsorption isotherm shows that BR moleculesare adsorbed layer by layer on the surface of oxide. Study of the adsorption phenomenon in this work suggest that copper(II) oxide has significant adsorptive and catalytic property. Dhaka Univ. J. Sci. 68(1): 7-12, 2020 (January)

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Wang, Congli, Bo Li, Weifen Niu, Shasha Hong, Bassam Saif, Songbai Wang, Chuan Dong, and Shaomin Shuang. "β-Cyclodextrin modified graphene oxide–magnetic nanocomposite for targeted delivery and pH-sensitive release of stereoisomeric anti-cancer drugs." RSC Advances 5, no. 108 (2015): 89299–308. http://dx.doi.org/10.1039/c5ra13082d.

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Kobyakov, Aleksandr V., Gennadiy S. Patrin, Vasiliy I. Yushkov, Yaroslav G. Shiyan, Roman Yu Rudenko, Nikolay N. Kosyrev, and Sergey M. Zharkov. "Magnetic and Resonance Properties of a Low-Dimensional Cobalt–Aluminum Oxide–Germanium Film Tunnel Junction Deposited by Magnetron Sputtering." Magnetochemistry 8, no. 10 (October 18, 2022): 130. http://dx.doi.org/10.3390/magnetochemistry8100130.

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The temperature behavior of saturation magnetization and the temperature behavior of the integral signal intensity in electron magnetic resonance spectra is experimentally studied comprehensively using a low-dimensional Al2O3/Ge/Al2O3/Co (aluminum oxide–cobalt–aluminum oxide–germanium) tunnel junction with different deposition velocities of a ferromagnetic metal (Co) thin layer and non-magnetic layers (Al2O3/Ge/Al2O3). The cobalt ferromagnetic layer was deposited on aluminum oxide in two ways: in one cycle of creating the structure and with atmospheric injection before deposition of the cobalt layer. The thermomagnetic curves revealed the appearance of minima observed at low temperatures on both sides of the cobalt layer. Possible sources of precession perturbations at low temperatures can be explained by: the influence of the Al2O3 layer structure on the Al2O3/Co interface; residual gases in the working chamber atmosphere and finely dispersed cobalt pellets distributed over the cobalt film thickness. The work offers information of great significance in terms of practical application, for both fundamental physics and potential applications of ultrathin films.

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Soler, Maria A. G. "Layer-by-layer assembled iron oxide based polymeric nanocomposites." Journal of Magnetism and Magnetic Materials 467 (December 2018): 37–48. http://dx.doi.org/10.1016/j.jmmm.2018.07.035.

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Hwang, Ji Yong, II Tae Kim, and Hyung Wook Choi. "Characteristics of Perovskite Solar Cells with ZnGa2O4:Mn Phosphor Mixed Polyvinylidene Fluoride Down-Conversion Layer." Journal of Nanoelectronics and Optoelectronics 16, no. 6 (June 1, 2021): 855–60. http://dx.doi.org/10.1166/jno.2021.3013.

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To reduce the manufacturing cost of perovskite solar cells, soda-lime glass and transparent conducting oxides such as indium tin oxide and fluorine-doped tin oxide are the most widely used substrates and lighttransmitting electrodes. However, the transmittance spectra of soda-lime glass, indium tin oxide, and fluorinedoped tin oxide show that all light near and below 330 nm is absorbed; thus, with the use of these substrates, light energy near and below 330 nm cannot reach the perovskite light-absorbing layer. It is expected that the overall solar cell can be improved if the wavelength can be adjusted to reach the perovskite solar cell absorbing layer through down-conversion of energy in the optical wavelength band. In this study, a polyvinylidene fluoride transparent film mixed with a ZnGa2O4:Mn phosphor was applied to the incident side of the perovskite solar cell with the intent to increase the light conversion efficiency without changing the internal bandgap energy and structure. By adding a phosphor layer to the external surface of PSC exposed to incident light, the efficiency of the cell was increased by the down-conversion of ultraviolet light (290 nm) to the visible region (509 nm) while maintaining the transmittance. To manufacture the perovskite solar cell, a TiO2-based mesoporous electron transport layer was spin-coated onto the substrate. The perovskite layer used in this experiment was CH3NH3PbI3 and was fabricated on a TiO2 layer. Spiro-OMeTAD solution was spin-coated as a hole-transport layer.

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Stavarache, Carmen, and Larysa Paniwynk. "Tailoring Polyelectrolyte Magnetic Capsules." Materiale Plastice 55, no. 2 (June 30, 2018): 192–95. http://dx.doi.org/10.37358/mp.18.2.4993.

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In the second part of this series polyelectrolyte multilayer capsules consisting of 6 bilayers of PAH/PSS and one layer of magnetic iron oxide nanoparticles namely D12, were fabricated. These capsules had their inner core removed once the 12 layers had been formed. The properties of the D12 capsules (mean diameter, concentration, dye intake and iron content) were analysed and compared with previously manufactured capsules which had the core dissolved after only 6 layers of coatings namely D6. The new sets of capsules had a greater capsule diameter, higher dye intake into the core and a higher iron oxide loading into the capsule layers.

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Papaparaskeva, G., M. M. Dinev, T. Krasia-Christoforou, R. Turcu, S. A. Porav, F. Balanean, and V. Socoliuc. "White Magnetic Paper with Zero Remanence Based on Electrospun Cellulose Microfibers Doped with Iron Oxide Nanoparticles." Nanomaterials 10, no. 3 (March 12, 2020): 517. http://dx.doi.org/10.3390/nano10030517.

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The preparation procedure of zero magnetic remanence superparamagnetic white paper by means of three-layer membrane configuration (sandwiched structure) is presented. The cellulose acetate fibrous membranes were prepared by electrospinning. The middle membrane layer was magnetically loaded by impregnation with an aqueous ferrofluid of 8 nm magnetic iron oxide nanoparticles colloidally stabilized with a double layer of oleic acid. The nanoparticles show zero magnetic remanence due to their very small diameters and their soft magnetic properties. Changing the ferrofluid magnetic nanoparticle volume fraction, white papers with zero magnetic remanence and tunable saturation magnetization in the range of 0.5–3.5 emu/g were prepared. The dark coloring of the paper owing to the presence of the black magnetite nanoparticles was concealed by the external layers of pristine white cellulose acetate electrospun fibrous membranes.

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Panduranga, Mohanchandra K., Zhuyun Xiao, Joseph D. Schneider, Taehwan Lee, Christoph Klewe, Rajesh Chopdekar, Padraic Shafer, et al. "Single magnetic domain Terfenol-D microstructures with passivating oxide layer." Journal of Magnetism and Magnetic Materials 528 (June 2021): 167798. http://dx.doi.org/10.1016/j.jmmm.2021.167798.

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Tsuchiya, Y., S. Le, M. Sano, T. Uesugi, S. Araki, H. Morita, and M. Matsuzaki. "RuRhMn and PtMn specular spin-valve with magnetic oxide layer." IEEE Transactions on Magnetics 36, no. 5 (2000): 2557–59. http://dx.doi.org/10.1109/20.908508.

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Mchedlov-Petrosyan, Petro O, and Manfred Martin. "Coupled Morphological Stability of the Multiple Phase Boundaries: Oxides in an Oxygen Potential Gradient. I. Single Oxide Layer." METALLOFIZIKA I NOVEISHIE TEKHNOLOGII 41, no. 11 (December 25, 2019): 1433–54. http://dx.doi.org/10.15407/mfint.41.11.1433.

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Tsuruta, Akihiro, Shuji Kawasaki, Masashi Mikami, Yoshiaki Kinemuchi, Yoshitake Masuda, Asaya Fujita, and Ichiro Terasaki. "Co-Substitution Effect in Room-Temperature Ferromagnetic Oxide Sr3.1Y0.9Co4O10.5." Materials 13, no. 10 (May 16, 2020): 2301. http://dx.doi.org/10.3390/ma13102301.

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We investigated the Co substitution effect for the magnetic properties in room-temperature ferromagnetic oxide Sr3.1Y0.9Co4O10.5. The substituted element (Al and Ga) and low-spin state Co3+, which was changed from a high-spin or intermediate-spin state by Al or Ga substitution, reduced the Curie temperature to even 1.5 times lower than the temperature estimated from a simple dilution effect. Al3+ preferentially substituted for intermediate-spin-state Co3+ in the ferrimagnetic CoO6 layer and deteriorated the saturation magnetization of Sr3.1Y0.9Co4O10.5. By contrast, Ga3+ substituted for high-spin-state Co3+ in the CoO6 layer and/or the antiferromagnetic CoO4.25 layer and enhanced the saturation magnetization per Co ion. These results indicate that the magnetic properties of Sr3.1Y0.9Co4O10.5 can be controlled by selectively substituting for Co3+ with different spin states.

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Suda, Masayuki, Yasuo Miyazaki, Yuki Hagiwara, Osamu Sato, Seimei Shiratori, and Yasuaki Einaga. "Photoswitchable Magnetic Layer-by-Layer Films Consisting of Azobenzene Derivatives and Iron Oxide Nanoparticles." Chemistry Letters 34, no. 7 (July 2005): 1028–29. http://dx.doi.org/10.1246/cl.2005.1028.

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31

Akrami, Mohammad, Mehdi Khoobi, Masoud Khalilvand-Sedagheh, Ismaeil Haririan, Abbas Bahador, Mohammad Ali Faramarzi, Shahla Rezaei, et al. "Evaluation of multilayer coated magnetic nanoparticles as biocompatible curcumin delivery platforms for breast cancer treatment." RSC Advances 5, no. 107 (2015): 88096–107. http://dx.doi.org/10.1039/c5ra13838h.

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Leuty, Zachary B., and Robert A. Mayanovic. "Investigations of the Magnetic Perpendicular Exchange Bias in L10 FePt/NiO Bilayer Thin Films." MRS Advances 3, no. 47-48 (2018): 2893–98. http://dx.doi.org/10.1557/adv.2018.421.

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ABSTRACTWe report on the exploration of perpendicular exchange bias in iron platinum/nickel oxide (FePt/NiO) bilayer thin films grown using pulsed laser deposition (PLD) on MgO (100) substrates. Exchange bias is an important property for giant magnetoresistance, and, as such has promise for applications in spin valves, magnetic sensors and magnetic random access memory. The magnetic L10 phase of FePt is known for having high perpendicular magnetic anisotropy, tunable coercivity/grain size and large magnetic storage density. The FePt layer was first deposited directly on MgO, followed by the deposition of the NiO layer on top of the FePt layer. The coercivity of the L10 FePt layer was tuned during growth to form a hard or soft magnetic layer. The FePt/NiO thin films grown for this study exhibit perpendicular exchange bias at 5K, as quantified using our SQUID measurements. XRD confirms parallel plane ordering between the MgO (200), FePt (002) and NiO (111) atomic planes while cross sectional TEM confirms the epitaxial growth of L10-FePt(001)<100>//MgO(100)<001> and the preferential growth of NiO on top of the FePt. Films of only FePt were grown to examine the surface architecture of the ferromagnetic layer and thus the interface of the FePt/NiO bilayer. The results from our XRD, TEM and magnetometry characterization of the FePt films and FePt/NiO bilayer thin films will be discussed.

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33

Kalam, Kristjan, Helina Seemen, Mats Mikkor, Taivo Jõgiaas, Peeter Ritslaid, Aile Tamm, Kaupo Kukli, et al. "Electrical and magnetic properties of atomic layer deposited cobalt oxide and zirconium oxide nanolaminates." Thin Solid Films 669 (January 2019): 294–300. http://dx.doi.org/10.1016/j.tsf.2018.11.008.

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34

Stavarache, Carmen, Mircea Vinatoru, Timothy Mason, and Larysa Paniwnyk. "The Effects of Magnetic Nanoparticles Incorporated in Polyelectrolyte Capsules." Materiale Plastice 54, no. 4 (December 30, 2017): 630–34. http://dx.doi.org/10.37358/mp.17.4.4914.

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Polyelectrolyte multilayer capsules are synthesized comprising of 12 total layers each containing a single layer of iron oxide nanoparticles in shells 4, 6, 8 or 10. A protein-labelled dye is embedded in the calcium carbonate template core as a model for the encapsulation of a drug. The core is dissolved after 6 layers are formed. Two types of magnetic nanoparticles are incorporated into various capsule shells: ferric oxide (Fe2O3, 50 nm) and iron oxide (Fe3O4, 15 nm), a 1:1 (vol.) mixture of the two types of nanoparticles suspensions is also used. Nanoparticle inclusion reduces the capsule sizes in all cases with the order of effect Fe3O4 [ Fe2O3 [ Fe2O3/Fe3O4 mixture. When Fe3O4 or a Fe2O3/Fe3O4 mixture is incorporated in layer 6 the reduction in size of the final capsules is less than expected. The number of surviving capsules containing nanoparticles are lower than control regardless of which of the nanoparticles is used but here the effect of Fe3O4 or a mixture of the two types of nanoparticles incorporated in layer 6 was slightly out of step. The amount of iron incorporated is almost the same regardless of which shell the nanoparticles were incorporated but the iron content using 50 nm nanoparticles is generally slightly higher than that obtained with 15 nm nanoparticles.

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Zhang, Dongzhi, Jingjing Liu, and Bokai Xia. "Layer-by-Layer Self-Assembly of Zinc Oxide/Graphene Oxide Hybrid Toward Ultrasensitive Humidity Sensing." IEEE Electron Device Letters 37, no. 7 (July 2016): 916–19. http://dx.doi.org/10.1109/led.2016.2565728.

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Gomez, Ismael J., W. Brandon Goodwin, Dan Sabo, Z. John Zhang, Kenneth H. Sandhage, and J. Carson Meredith. "Three-dimensional magnetite replicas of pollen particles with tailorable and predictable multimodal adhesion." Journal of Materials Chemistry C 3, no. 3 (2015): 632–43. http://dx.doi.org/10.1039/c4tc01938e.

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Layer-by-layer surface sol-gel chemistry and controlled thermal treatment allow for careful adjustment of the amount, type, and crystal size of iron oxide in pollen replicas, giving the biogenic magnetic particles tunable adhesion characteristics.

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37

Bangle, Rachel E., Jenny Schneider, Quentin Loague, Matthew Kessinger, Andressa V. Müller, and Gerald J. Meyer. "Free Energy Dependencies for Interfacial Electron Transfer from Tin-Doped Indium Oxide (ITO) to Molecular Photoredox Catalysts." ECS Journal of Solid State Science and Technology 11, no. 2 (February 1, 2022): 025003. http://dx.doi.org/10.1149/2162-8777/ac5169.

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John B. Goodenough proposed that interfacial electron transfer kinetics from main group metal oxides should be fundamentally different from that of transition metal oxides, an expectation that has not been widely tested. Herein, the kinetics for interfacial electron transfer from mesoporous transparent conductive oxide Tin-doped Indium Oxide (ITO) to four photoredox catalysts (PCs) were characterized in acetonitrile electrolytes. The photocatalysts had the form: [Ru(4,4ʹ-R2-2,2′-bipyridine)2(4,4ʹ-(PO3H2)2-2,2′-bipyridine)]2+, where R was H, methoxy, tert-butyl, and Br. The impact of the surface binding group was characterized with [Ru(2,2′-bipyridine)2(4,4ʹ-(CO2H)2-bpy)]2+. The interfacial electron transfer reaction ITO(e−)∣PC+ → ITO∣PC was quantified by nanosecond absorption spectroscopy as a function of the applied potential (and hence ‒ΔG°). Specific conditions of applied potential were identified where the kinetics were sensitive to the incident irradiance. A layer-by-layer method was used to insert ionic methylene bridge(s) between the PC and the oxide surface. Marcus-Gerischer analysis of the kinetic data indicates non-adiabatic interfacial electron transfer with total reorganization energies that increase when bridges were placed between the photocatalyst and the ITO surface.

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Kong, S. H., K. Mizuno, T. Okamoto, and S. Nakagawa. "Oxide seed layer with low surface energy to attain fine grains in magnetic layers." Journal of Applied Physics 93, no. 10 (May 15, 2003): 6781–83. http://dx.doi.org/10.1063/1.1557754.

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Markert, J. T., T. C. Messina, B. Dam, J. Huijbregste, J. H. Rector, and R. Griessen. "Infinite-layer copper-oxide laser-ablated thin films: substrate, buffer-layer, and processing effects." IEEE Transactions on Appiled Superconductivity 13, no. 2 (June 2003): 2684–86. http://dx.doi.org/10.1109/tasc.2003.811956.

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GIUNCHI, G., S. CERESARA, R. CORTI, T. PETRISOR, A. MANCINI, and G. CELENTANO. "A NEW METALLIC NON MAGNETIC SUBSTRATE FOR COATED TAPE SUPERCONDUCTORS." International Journal of Modern Physics B 14, no. 25n27 (October 30, 2000): 3134–38. http://dx.doi.org/10.1142/s0217979200003435.

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The high Tc superconductors, realised in form of coated tapes, rely on the quality of the substrate on which they are growing. Furthermore the aim to produce a long superconducting tape, carrying the high engineering current densities typical of the power applications, push the search of a very robust and thin metallic tape as substrate. Looking for a trade off between the mechanical strength at high temperature and the chemical and structural compatibility of the substrate with the growing oxide superconductors, a new metallic alloy is proposed and a systems combining the metallic tape plus one micron thick textured oxide buffer layer is presented. The system fulfils also the demanding characteristics of a low manufacturing cost, being based on production technologies easily scalable at high volumes, like the melt flow casting of the metallic tape and the Electron Beam (EB) evaporation of the oxide film. The main physical characteristic of the new substrate, with the deposited buffer layer, are presented.

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Teng, Xiaowei, and Hong Yang. "Iron Oxide Shell as the Oxidation-Resistant Layer in SmCo5@Fe2O3 Core–Shell Magnetic Nanoparticles." Journal of Nanoscience and Nanotechnology 7, no. 1 (January 1, 2007): 356–61. http://dx.doi.org/10.1166/jnn.2007.18035.

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This paper presents a synthesis of magnetic nanoparticles of samarium cobalt alloys and the use of iron oxide as a coating layer to prevent the rapid oxidation of as-made Sm–Co nanoparticles. The colloidal nanoparticles of Sm–Co alloys were made in octyl ether using samarium acetylacetonate and dicobalt octacarbonyl as precursors in a mixture of 1,2-hexadecanediol, oleic acid, and trioctylphosphine oxide (TOPO). Such Sm–Co nanoparticle could be readily oxidized by air and formed a CoO antiferromagnetic layer. Exchange biasing was observed for the surface oxidized nanoparticles. In situ thermal decomposition of iron pentacarbonyl was used to create iron oxide shells on the Sm–Co nanoparticles. The iron oxide shell could prevent Sm–Co nanoparticles from rapid oxidation upon the exposure to air at ambient conditions.

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42

Gervits, Natalia E., Andrey A. Gippius, Alexey V. Tkachev, Evgeniy I. Demikhov, Sergey S. Starchikov, Igor S. Lyubutin, Alexander L. Vasiliev, et al. "Magnetic properties of biofunctionalized iron oxide nanoparticles as magnetic resonance imaging contrast agents." Beilstein Journal of Nanotechnology 10 (October 2, 2019): 1964–72. http://dx.doi.org/10.3762/bjnano.10.193.

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Background: One of the future applications of magnetic nanoparticles is the development of new iron-oxide-based magnetic resonance imaging (MRI) negative contrast agents, which are intended to improve the results of diagnostics and complement existing Gd-based contrast media. Results: Iron oxide nanoparticles designed for use as MRI contrast media are precisely examined by a variety of methods: powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, Mössbauer spectroscopy and zero-field nuclear magnetic resonance (ZF-NMR) spectroscopy. TEM and XRD measurements reveal a spherical shape of the nanoparticles with an average diameter of 5–8 nm and a cubic spinel-type crystal structure of space group Fd−3m. Raman, Mössbauer and NMR spectroscopy clearly indicate the presence of the maghemite γ-Fe2O3 phase. Moreover, a difference in the magnetic behavior of uncoated and human serum albumin coated iron oxide nanoparticles was observed by Mössbauer spectroscopy. Conclusion: This difference in magnetic behavior is explained by the influence of biofunctionalization on the magnetic and electronic properties of the iron oxide nanoparticles. The ZF-NMR spectra analysis allowed us to determine the relative amount of iron located in the core and the surface layer of the nanoparticles. The obtained results are important for understanding the structural and magnetic properties of iron oxide nanoparticles used as T 2 contrast agents for MRI.

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43

Huang, Zhenyi, Huaqin Huang, Hao He, Zhaoyang Wu, Xuesong Wang, and Rui Wang. "Effect of Various Metal Oxide Insulating Layers on the Magnetic Properties of Fe-Si-Cr Systems." Coatings 13, no. 4 (April 20, 2023): 804. http://dx.doi.org/10.3390/coatings13040804.

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Iron-based soft magnetic composites (SMCs) are the key components of high-frequency electromagnetic systems. Selecting a suitable insulating oxide layer and ensuring the integrity and homogeneity of the heterogeneous core–shell structure of SMCs are essential for optimizing their magnetic properties. In this study, four types of SMCs—Fe-Si-Cr/ZrO2, Fe-Si-Cr/TiO2, Fe-Si-Cr/MgO, and Fe-Si-Cr/CaO—were prepared via ball milling, followed by hot-press sintering. The differences between the microscopic morphologies and magnetic fproperties of the Fe-Si-Cr/AOx SMCs prepared using four different metal oxides were investigated. ZrO2, TiO2, MgO, and CaO were successfully coated on the surface of the Fe-Si-Cr alloy powders through ball milling, forming a heterogeneous Fe-Si-Cr/AOx core–shell structure with the Fe-Si-Cr alloy powder as the core and the metal oxide as the shell. ZrO2 is relatively hard and less prone to breakage and refinement during ball milling, resulting in a lower degree of agglomeration on the surface of the composites and prevention of peeling and collapse during hot-press sintering. When ZrO2 was used as the insulation layer, the magnetic dilution effect was minimized, resulting in the highest resistivity (4.2 mΩ·cm), lowest total loss (580.8 kW/m3 for P10mt/100kHz), and lowest eddy current loss (470.0 kW/m3 for Pec 10mt/100kHz), while the permeability stabilized earlier at lower frequencies.

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Sandu, Viorel, Ivan Ion, Paul Litra-Cristian, and Elena Sandu. "Fabrication of Superconducting MgB₂-Based Nanocomposites with Magnetic Inclusions by Spark Plasma Sintering." Advanced Materials Research 569 (September 2012): 3–6. http://dx.doi.org/10.4028/www.scientific.net/amr.569.3.

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We present the fabrication, structural, and transport properties of MgB2-based ceramic composites with magnetic nanospheres fabricated by spark plasma sintering. The nanospheres are either carbon–encapsulated iron or iron oxide. The former nanospheres have been prepared by laser pyrolysis whereas the iron oxide was obtained by the pyrolysis of the polysiloxane-based copolymers embedded into MgB2 matrix during the sintering process. The structural data show the shrinkage of the a-axis lattice constant as a result of the partial carbon substitution for boron. However, the transport data suggest that carbon diffusion is limited to the outer layer of the MgB2 grains in both cases.

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45

Jõgiaas, Taivo, Aivar Tarre, Hugo Mändar, Jekaterina Kozlova, and Aile Tamm. "Nanoindentation of Chromium Oxide Possessing Superior Hardness among Atomic-Layer-Deposited Oxides." Nanomaterials 12, no. 1 (December 29, 2021): 82. http://dx.doi.org/10.3390/nano12010082.

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Chromium (III) oxide is a technologically interesting material with attractive chemical, catalytic, magnetic and mechanical properties. It can be produced by different chemical and physical methods, for instance, by metal–organic chemical vapor deposition, thermal decomposition of chromium nitrate Cr(NO3)3 or ammonium dichromate (NH4)2Cr2O7, magnetron sputtering and atomic layer deposition. The latter method was used in the current work to deposit Cr2O3 thin films with thicknesses from 28 to 400 nm at deposition temperatures from 330 to 465 °C. The phase composition, crystallite size, hardness and modulus of elasticity were measured. The deposited Cr2O3 thin films had different structures from X-ray amorphous to crystalline α-Cr2O3 (eskolaite) structures. The averaged hardness of the films on SiO2 glass substrate varied from 12 to 22 GPa and the moduli were in the range of 76–180 GPa, as determined by nanoindentation. Lower values included some influence from a softer deposition substrate. The results indicate that Cr2O3 could be a promising material as a mechanically protective thin film applicable, for instance, in micro-electromechanical devices.

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46

Zhang, Hongxing, Yiwei Zhang, Yuming Zhou, Chao Zhang, Qianli Wang, Yuanmei Xu, and Mingyu Zhang. "Synthesis and characterization of a multifunctional nanocatalyst based on a novel type of binary-metal-oxide-coated Fe3O4–Au nanoparticle." RSC Advances 6, no. 22 (2016): 18685–94. http://dx.doi.org/10.1039/c5ra27136c.

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A novel type of binary-metal-oxide-coated Au nanocatalyst, including a mixed oxide layer, a moveable magnetic Fe₃O₄ core and some Au NPs of 2–5 nm, has been synthesized successfully by a facile hydrothermal synthesis method.

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47

BÉG, O. ANWAR, M. FERDOWS, S. SHAMIMA, and M. NAZRUL ISLAM. "NUMERICAL SIMULATION OF MARANGONI MAGNETOHYDRODYNAMIC BIO-NANOFLUID CONVECTION FROM A NON-ISOTHERMAL SURFACE WITH MAGNETIC INDUCTION EFFECTS: A BIO-NANOMATERIAL MANUFACTURING TRANSPORT MODEL." Journal of Mechanics in Medicine and Biology 14, no. 03 (March 13, 2014): 1450039. http://dx.doi.org/10.1142/s0219519414500390.

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Laminar magnetohydrodynamic Marangoni-forced convection boundary layer flow of a water-based biopolymer nanofluid containing nanoparticles from a non-isothermal plate is studied. Magnetic induction effects are incorporated. A variety of nanoparticles are studied, specifically, silver, copper, aluminium oxide and titanium oxide. The Tiwari–Das model is utilized for simulating nanofluid effects. The normalized ordinary differential boundary layer equations (mass, magnetic field continuity, momentum, induced magnetic field and energy conservation) are solved subject to appropriate boundary conditions using Maple shooting quadrature. The influence of Prandtl number (Pr), magnetohydrodynamic body force parameter (β), reciprocal of magnetic Prandtl number (α) and nanofluid solid volume fraction (φ) on velocity, temperature and magnetic stream function distributions is investigated in the presence of strong Marangoni effects (ξ i.e., Marangoni parameter is set as unity). Magnetic stream function is accentuated with body force parameter. The flow is considerably decelerated as is magnetic stream function gradient, with increasing nanofluid solid volume fraction, whereas temperatures are significantly enhanced. Interesting features in the flow regime are explored. The study finds applications in the fabrication of complex biomedical nanofluids, biopolymers, etc.

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Che, By Hui Xin, Swee Pin Yeap, Abdul Latif Ahmad, and JitKang Lim. "Layer-by-layer assembly of iron oxide magnetic nanoparticles decorated silica colloid for water remediation." Chemical Engineering Journal 243 (May 2014): 68–78. http://dx.doi.org/10.1016/j.cej.2013.12.095.

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49

Ezzaier, Hinda, Jéssica Marins, Cyrille Claudet, Gauvin Hemery, Olivier Sandre, and Pavel Kuzhir. "Kinetics of Aggregation and Magnetic Separation of Multicore Iron Oxide Nanoparticles: Effect of the Grafted Layer Thickness." Nanomaterials 8, no. 8 (August 17, 2018): 623. http://dx.doi.org/10.3390/nano8080623.

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In this work, we have studied field-induced aggregation and magnetic separation—realized in a microfluidic channel equipped with a single magnetizable micropillar—of multicore iron oxide nanoparticles (IONPs) also called “nanoflowers” of an average size of 27 ± 4 nm and covered by either a citrate or polyethylene (PEG) monolayer having a thickness of 0.2–1 nm and 3.4–7.8 nm, respectively. The thickness of the adsorbed molecular layer is shown to strongly affect the magnetic dipolar coupling parameter because thicker molecular layers result in larger separation distances between nanoparticle metal oxide multicores thus decreasing dipolar magnetic forces between them. This simple geometrical constraint effect leads to the following important features related to the aggregation and magnetic separation processes: (a) Thinner citrate layer on the IONP surface promotes faster and stronger field-induced aggregation resulting in longer and thicker bulk needle-like aggregates as compared to those obtained with a thicker PEG layer; (b) A stronger aggregation of citrated IONPs leads to an enhanced retention capacity of these IONPs by a magnetized micropillar during magnetic separation. However, the capture efficiency Λ at the beginning of the magnetic separation seems to be almost independent of the adsorbed layer thickness. This is explained by the fact that only a small portion of nanoparticles composes bulk aggregates, while the main part of nanoparticles forms chains whose capture efficiency is independent of the adsorbed layer thickness but depends solely on the Mason number Ma. More precisely, the capture efficiency shows a power law trend Λ ∝ M a − n , with n ≈ 1.4–1.7 at 300 < Ma < 104, in agreement with a new theoretical model. Besides these fundamental issues, the current work shows that the multicore IONPs with a size of about 30 nm have a good potential for use in biomedical sensor applications where an efficient low-field magnetic separation is required. In these applications, the nanoparticle surface design should be carried out in a close feedback with the magnetic separation study in order to find a compromise between biological functionalities of the adsorbed molecular layer and magnetic separation efficiency.

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Ying, Qi, Taiguang Li, and Yongmei Hao. "Preparation of Magnetic Graphene Photocatalytic Nano-adsorbent for the Sustainable Removal of Polycyclic Aromatic Hydrocarbons from Aqueous Solution." Journal of Physics: Conference Series 2463, no. 1 (March 1, 2023): 012003. http://dx.doi.org/10.1088/1742-6596/2463/1/012003.

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Abstract Magnetic graphene oxide-SiO2-TiO2 (MGST) composite was prepared for the absorption and further photodegradation of PAHs to reduce the risk of PAHs in the water environment. Magnetic graphene oxide (MGO) was obtained by introducing Fe3O4 to graphite oxide (GO). Furthermore, the suitable SiO2 layer was wrapped on the MGO for further modification with TiO2. Finally, the functional MGST composite with uniform morphology was obtained. Naphthalene, phenanthrene and pyrene were selected as models. It was found that the adsorption capacity of MGST showed the order of naphthalene (NAP) < phenanthrene (PHE) < pyrene (PYR).

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Journal articles on the topic 'Layer magnetic oxide'

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