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Solid state synthesis of some new Mx-CuSb2O6-CuSb2O4 (Mx=None, Fe, Ni, Ce and Yb) nanocomposites was introduced in the present research study. The physicoelectrochemical properties of synthesized nanocomposites were investigated by different techniques, such as XRPDT, Rietveld, FTIR, FESEM, UV-Vis, VSM, CV and EIS. Rietveld analysis data revealed that all of the synthesized samples display the monoclinic crystal phase with the space group of P21/n. The estimated direct band gap energy of the obtained nanocomposites was in the range of 2.0 to 2.7 eV, which confirms that are active in ultraviolet-visible region. The VSM data indicated that the maximum magnetic behavior was found for Ni doped — Cu−Sb−O nanocomposite. Also, the catalytic performance of nanocomposites to synthesis 2-amino-4H-benzochromenes under ultrasonic and microwave was investigated. The considered parameters, such as solvent type, catalyst amount and reaction time, influencing the yield of the 4H-benzochromene reaction were studied. The maximum yield for the synthesizing of the 4H-benzochromene compounds was obtained when EtOH was used as the reaction solvent. The catalyst amount and reaction time were 15 mol% and 8 min, respectively, under ultrasonic conditions, while benzaldehyde was used as an aldehyde derivative. [ABSTRACT FROM AUTHOR]

The magnetic shielding device is used to provide an extreme weak magnetic field, which plays a key role in variety of fields. Since the high-permeability material constituting the magnetic shielding device determines the magnetic shielding performance, it is important to evaluate the property of the high-permeability material. In this paper, the relationship between the microstructure and the magnetic properties of the high-permeability material is analyzed using minimum free energy principle based on magnetic domain theory, and the test method of the material's microstructure including the material composition, the texture and the grain structure to reflect the magnetic properties is put forward. The test result shows that the grain structure is closely related to the initial permeability and the coercivity, which is highly consistent with the theory. As a result, it provides a more efficient way to evaluate the property of the high-permeability material. The test method proposed in the paper has important significance in the high efficiency sampling inspection of the high-permeability material. [ABSTRACT FROM AUTHOR]

Three new cyanide-bridged heterobimetallic complexes {[Cu(L)]2[Cr(CN)5(NO)]}ClO4·2H2O (1), {{[Cu(cyclam)][Fe(CN)5(NO)]}·H2O}n (2), {{[Cu(cyclam)]3[Cr(CN)5(NO)]2}·CH3OH·4H2O}n (3) (L=2,12-dimethyl-3,7,11,17-tetraazabicyclo [11.3.1] heptadeca-1 (17), 13, 15-triene, cyclam=1,4,8,11-tetraazacyclodecane) have been successfully assembled from the pentacyanometalates and two copper(II) compounds and characterized by elemental analysis, IR spectroscopy and X-ray structure determination. X-ray structural analysis revealed that the Complex 1 is a cationic trinuclear CrCu2 entity with the positive charge balanced by ClO4− ion, while complexes 2 and 3 were structurally characterized showing a 1D chain. The magnetic properties of the reported cyanide-bridged complexes have been experimentally studied and theoretically simulated, disclosing the ferromagnetic interaction between the Cr(I) ion and the Cu(II) ion through the cyanide bridge. [ABSTRACT FROM AUTHOR]

We studied the effect of Eu3+ substitution on the structural, magnetic and magnetocaloric properties of La0.7–xEuxBa0.3MnO3 (x = 0, 0.02, 0.04, 0.06 and 0.08) (LEBMO). The material is prepared by solid-state sintering method. X-ray diffraction and structural refinement parameters indicate that all the synthesized samples have single-phase hexagonal structure. Magnetic measurements indicate that Curie temperature (TC) of the samples decrease with increasing Eu3+ content, because of the weakening of double exchange interaction. All samples present a second-order ferromagnetic to paramagnetic phase transition. Magnetic entropy change (ΔSM) of the samples increases as the Eu3+ content enhance. When x = 0.08, the TC of the sample is 258.6 K and the maximum value of ΔSM reaches 3.27 J kg−1 K−1 at 5 T of a magnetic field. These results indicate that the material can be used as an ideal working material for the normal temperature magnetic refrigeration. [ABSTRACT FROM AUTHOR]

The high undercooling of binary Co-4.54%Sn alloy has a significant influence on its microstructural characteristics and physical properties. Here, we report that the dendritic growth and physical properties of broad-temperature-range Co-4.54%Sn alloy remarkably depends on the undercooling during the rapid solidification. The maximum undercooling attains 208 K at molten state, and the dendritic growth velocity is quite sluggish in highly undercooled liquid Co-4.54%Sn alloy because it has a broad solidification range of 375 K (0.21 T L ); the maximum value is only 0.95 m/s at the undercooling of 175 K, which then decreases with undercooling. The microstructure refines visibly and the volume fraction of the interdendritic βCo3Sn2 phase obviously decreases with undercooling. The microhardness and electrical resistivity increase with undercooling owing to the enhancement of solute content of the primary αCo phase and refinement of the microstructure where the increased crystal boundary hinders the electronic transmission. Meanwhile, the saturation magnetization also reduces with undercooling due to the crystal particle and boundary increasing significantly, and the dendritic growth velocity and solute content increase in the primary αCo phase under rapid solidification. [ABSTRACT FROM AUTHOR]

The effect of annealing temperature (TA) at 600–900 °C on structure and magnetic properties of the melt-spun Sm8.6Fe85.9Co4.3Zr1.2 alloys and its nitrides was investigated. Results show that the melt-spun powder is TbCu7-type SmFe9 single phase. X-ray diffractometer (XRD) Rietveld refinement shows that the lattice parameter a increases, c and c/a decrease with the increase in TA at 600–700 °C. This is due to the tendency of nitrogen entering into the 3f site (1/2, 0, 0) during the nitridation process, which is good for the magnetic properties. The phase transforms from TbCu7-type SmFe9 to Th2Zn17-type Sm2Fe17 at above 800 °C. Scanning electron microscopy (SEM) images show that the amount of surface defects of melt-spun powder which are harmful for magnetic properties decreases at first and then increases as TA increases. The coercivity (Hcj) and maximum magnetic energy product ((BH)max) of its nitrides increase first and then decrease as a function of TA. And the remanence (Br) always shows a decrease. The optimal magnetic properties of Hcj = 748 kA·m−1, Br = 0.92 T, (BH)max = 118 kJ·m−3 are obtained by annealing at 675 °C for 2 h and then nitriding at 460 °C for 10 h. [ABSTRACT FROM AUTHOR]

A new polyoxovanadate‐based metal‐organic polyhedron, termed V‐MOP‐19, constructed from pentanuclear {V5O9Cl} clusters and 1,4‐naphthalenedicarboxylic acid linkers, was successfully fabricated via the solvothermal method. Structural analysis revealed that V‐MOP‐19 adopts the cubic symmetry featured with an octahedral pore cage of 15.7 Å. Full characterization of V‐MOP‐19 was measured by Fourier transform infrared (FT‐IR), Raman spectroscopy, powder X‐ray diffraction (PXRD), scanning electron microscopy (SEM), energy‐dispersive X‐ray (EDX), transmission electron microscopy (TEM), thermogravimetric and differential scanning calorimetry analysis (TGA‐DSC), N2 sorption isotherm and elemental analysis (EA). The band gap energy of V‐MOP‐19, measured by UV‐Vis diffuse reflectance spectroscopy (UV‐Vis/DRS), is determined to be 2.38 eV. Moreover, the cyclic voltammetry investigation confirms a high correspondence of the band gap value (2.41 eV) with the mentioned UV‐Vis/DRS study. In particular, V‐MOP‐19 exhibits a unique magnetic property with remarkable coercivity and remanent magnetization value. These findings demonstrate that V‐MOP‐19 could be used as a potential candidate in further photocatalytic and magnetic investigations. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDs) are two-dimensional (2D) materials with remarkable electrical, optical, and chemical properties. One promising strategy to tailor the properties of TMDs is to create alloys through a dopant-induced modification. Dopants can introduce additional states within the bandgap of TMDs, leading to changes in their optical, electronic, and magnetic properties. This paper overviews chemical vapor deposition (CVD) methods to introduce dopants into TMD monolayers, and discusses the advantages, limitations, and their impacts on the structural, electrical, optical, and magnetic properties of substitutionally doped TMDs. The dopants in TMDs modify the density and type of carriers in the material, thereby influencing the optical properties of the materials. The magnetic moment and circular dichroism in magnetic TMDs are also strongly affected by doping, which enhances the magnetic signal in the material. Finally, we highlight the different doping-induced magnetic properties of TMDs, including superexchange-induced ferromagnetism and valley Zeeman shift. Overall, this review paper provides a comprehensive summary of magnetic TMDs synthesized via CVD, which can guide future research on doped TMDs for various applications, such as spintronics, optoelectronics, and magnetic memory devices. [ABSTRACT FROM AUTHOR]

Two novel Co(II) and Ni(II) complexes Co(dpza)2 (1) and Ni(dpza)2 (2) (Hdpza is 2,2-di(1H-pyrazol-1-yl)acetic acid) were successfully synthesized via solvothermal method. The two complexes namely, 1 and 2 are isostructural exhibiting lantern-shaped configurations as illustrated by the structural analysis. The structures of the two complexes have been determined by single-crystal X-ray diffraction, FT-IR, and TGA. Magnetic property of 1 in the 2–300 K also has been investigated which displays dominant ferromagnetic behavior. Hirshfeld surface analysis reveals that the main interactions for complex two are O···H/H···O and H···H contacts. [ABSTRACT FROM AUTHOR]

A Bi2O3 nanomaterial was fabricated by a facile and low temperature solid state method using a basic bismuth nitrate raw compound at 400 ˚C and 14 h. Rietveld analysis data indicated that α-Bi2O3 was crystallized well in monoclinic crystal system with the space group of P121/c1. The morphology of the synthesized material was studied by field emission scanning electron microscope (FESEM). The direct band gap energy (Eg) value was calculated by ultraviolet – visible (UV-Vis) spectroscopy. The peaks at 400 – 550 cm-1 are assigned to oxygen – metal – oxygen (O-M-O) vibrations. The data showed that the Eg of the synthesized material was about 2.2 eV. In addition, the vibrating-sample magnetometer (VSM) analysis data confirmed that the synthesized sample had ferromagnetic behavior. Further, gas sensing property of the synthesized Bi2O3 nanomaterial for carbon monoxide gas was studied, and the data confirmed the good sensitivity of the prepared sensor at low CO concentrations.

Polynuclear metal clusters, particularly those with aesthetically appealing structures, are of increasing interest. In this study, by employing C4 symmetrical macrocyclic silsesquioxane ligand, a novel tridecanuclear Gd(III) cluster (Gd13) with a {Gd13O8} core featuring unprecedent body-centered Archimedean cuboctahedron conformation is realized using an efficient solvothermal method instead of conventional Schlenk techniques. To the best of our knowledge, Gd13 cluster is thus far the highest nuclearity of lanthanide-silsesquioxane. Moreover, a magnetic study reveals a weak antiferromagnetic interaction between adjacent Gd ions in the cluster. In addition, Gd13 exhibits cryogenic magnetocaloric effects with a maximum −ΔSM value of 20 J kg−1 K−1 at 2 K and ΔH = 7.0 T.

Two isomorphic one-dimensional coordination polymers, [Mn(tp)0.5(HL)(H2O)]n·nH2O and [Co(tp)0.5(HL)(H2O)]n·nH2O [H2L = 3-(1H-pyrazol-4-yl)-5-(pyridin-2-yl)-1,2,4-triazole; H2tp = terephthalic acid], were synthesized under hydrothermal conditions. The title compounds were characterized by single-crystal and powder X-ray diffractions, FTIR, and TGA. Both compounds crystallize in triclinic, space group P-1. They display a one-dimensional chain structure, those are connected by O–H···O hydrogen bonds to generate 2D structure. In addition, temperature-dependent magnetic susceptibility studies for the complexes were described. The results indicate that domain a weak antiferromagnetic exchange coupling between the adjacent Mn(II) centers in [Mn(tp)0.5(HL)(H2O)]n·nH2O , and the magnetic susceptibility from 60 to 300 K obeys the Curie–Weiss law with a Weiss constant θ of –11.84 K in [Co(tp)0.5(HL)(H2O)]n·nH2O. [ABSTRACT FROM AUTHOR]

In this paper, magnetic and structural properties' and graphene nanoparticles' influence on photocatalytic activity of BiFeO3 ceramics are reported. BiFeO3 ceramics were prepared by the sol–gel process and sintering at different temperatures from 400 to 700 °C to get phase pure BiFeO3 ceramics. X-ray diffraction patterns indicated pure phase with sharp peaks for sample sintered at 600 °C. Rietveld analysis showed the presence of pure phase samples of rhombohedral perovskite structure with R3c symmetry expect sample sintered at 700 °C. Bond valance sum analysis showed that Fe cations are inadequately bonded, while the Bi cations are excessively bonded in BiFeO3 structure. First-order Raman modes along with few second-order modes belonging to rhombedral crystal were observed in Raman spectra. X-ray photoelectron spectroscopy showed the presence of mixed oxidation states (Fe2+/Fe3+) with Fe3+ dominance. Vibrating sample magnetometer analysis indicated weak ferromagnetism along with strong dependence of magnetic characteristics on sintering temperatures. The ferromagnetic saturation magnetization ( M FM S) and remnant magnetization decreased from 0.057 to 0.0049 emu/g and 0.0150 to 0.0009 emu/g, respectively, with increasing sintering temperature. The photocatalytic activity of pure BiFeO3 and graphene nanoparticle-modified BiFeO3 samples was recorded. It was observed that BiFeO3 with graphene nanoparticles exhibited good degradation toward methylene blue dye when exposed to visible light irradiation. [ABSTRACT FROM AUTHOR]

In this paper, a new nonanuclear terbium cluster {Tb9 (L)4 (μ4-OH)2 (μ3-OH)8 (μ2-OCH3)4 (NO3)8 (H2O)8} (OH)·2H2O(1) was synthesized by 2,6-dimethoxyphenol (HL) and Tb(NO3)2·6H2O. The cluster was characterized via XRD, elemental analysis, infrared spectrum and thermogravimetric analysis. The magnetic property were also studied. X-ray single-crystal diffraction analysis indicates that the cluster is orthorhombic, the space group is I222, the crystal cell parameters are a = 1. 532 8 (3) nm, b = 1. 796 9 (4) nm, c = 1. 863 5 (4) nm, α = β = γ = 90°, V = 5. 132 6 (19) nm³. The nonanuclear skeleton formed by metal centers in the cluster that connected by μ4-OH and μ3-OH presents an interesting hourglass like topology. The central Tb ion has a slightly twisted tetragonal pyramid geometry, while the other Tb ions have a slightly deformed dodecahedral configuration. Magnetic investigations reveal that the weak antiferromagnetic interactions between adjacent metal ions exist in cluster 1, but no obvious slow magnetic relaxation behavior is shown due to the rapid magnetic quantum tunneling effect. [ABSTRACT FROM AUTHOR]

In this study, CuS/Fe3O4 composite structures were prepared in a two-step process. Initially, we used a simple solvothermal method to synthesize CuS nanostructures. Hydrothermal method was employed to form CuS/Fe3O4 composites. We characterized the particles using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). The particles exhibit an oxidase-like activity using the colorless 3,3′,5,5′-tetramethylbenzidine (TMB) as oxidase substrate. The presence of chromium (VI) increases the oxidase-like activity and is dependent on the concentration. The UV/visible absorption intensity of the oxidized TMB (oxTMB) increases with the concentration of chromium (VI) which provides a route to colorimetric determination of chromium (VI). We noticed a limit of detection as small as 60 nM and a wide linear dynamic range of 0–1500 µM. We found a high selectivity of this method for chromium (VI) against potentially interference cations and anions. Its applicability for determination of chromium (VI) in real environmental samples is demonstrated using tap water. This result demonstrates the capability of the method in determination of chromium (VI) in real samples. [ABSTRACT FROM AUTHOR]

A new cobalt(II) compound with the formula [Co(5-Br-pyc)(2,2′-bipy)(H2O)(Cl)]·2H2O (1·H2O) (5-Br-Hpyc = 5-bromo-pyridine-2-carboxylic acid, 2,2′-bipy = 2,2′-bipyridine) has been hydrothermally synthesized and well characterized. The X-ray single-crystal diffraction analysis showed that 1⋅2H2O has crystallizes in the monoclinic system, space group P21/c (no. 14). The Co(II) center was octahedrally bonded by one bidentate chelate 5-Br-pyc anion and one 2,2′-bipy, one water molecule as well as one chloride anion to form the mononuclear structure of 1⋅2H2O. Complex 1⋅2H2O forms a 3D network through abundant O–H⋅⋅⋅O hydrogen bonds and π⋅⋅⋅π stacking interactions. Notably, the 5-Br-Hpyc ligand was in situ generated by decarboxylation of the 3-bromo-pyridine-2,6-dicarboxylic acid (3-Br-H2pydc) precursor selectively on 2-position under hydrothermal conditions. The magnetic properties, the Hirshfeld surface structure and the synthetic process for 1⋅2H2O have been carefully described and discussed. [ABSTRACT FROM AUTHOR]

This study is aimed to synthesize and characterize spinel vanadium nano-ferrite (VFe 2 O 4) for the electrochemical sensing of acetaminophen (Ac) in pharmaceutical and biological samples. The VFe 2 O 4 was synthesized by hydrothermal method followed by characterization of structural, magnetic, and electrochemical properties. The XRD and SEM analysis confirmed the cubic single-phase spinel crystalline structure and irregular shaped VFe 2 O 4 micro-grains respectively. The VFe 2 O 4 exhibited excellent superparamagnetic properties with a low value of coercivity. The VFe 2 O 4 coated on the glassy carbon electrode (GCE) surface by drop costing method for the fabrication of the VFe 2 O 4 /GCE. The oxidative peak at a lower potential onto the surface of VFe 2 O 4 /GCE confirmed its modification for the electrocatalytic oxidative sensing of Ac. The proposed electrochemical method was optimized for quantitative sensing of Ac followed by the linear response (R2 = 0.9897) with limits of detection and quantification as 8.20 and 27.5 nM, respectively. Interference studies of possible competing species (glucose, ascorbic acid, uric acid, fructose, glycine, alanine, naproxen, and methocarbamol) proved the selectivity of the proposed method. The proposed VFe 2 O 4 /GCE was successfully utilized for quantitative routine sensing of Ac in the biological fluids and pharmaceutical samples (recovery of Ac > 98.0% and relative standard deviation < 2.0%). [ABSTRACT FROM AUTHOR]

In order to study the effects of rare earth La–Ce alloying treatment on the characteristics of inclusions in non-oriented silicon steels, industrial experiments were conducted studying the composition, morphology, size and quantity of inclusions in W350 non-oriented silicon steel during the RH (Ruhrstahl-Hereaeus) refining process and tundish process, after rare earth treatment. The products were analyzed by means of ICP-MS (inductively coupled plasma mass spectrometry), SEM/EDS (scanning electron microscope-energy dispersive spectrometry), and ASPEX (automated SEM/EDS inclusion analysis). The research results showed that the types of inclusions in experimental steel changed significantly after rare earth treatment. The types of inclusions after RE (rare earth) treatment are typically rare earth composite inclusions that are mainly composed of (La, Ce)Al2O3, and conventional inclusions. The addition of rare earth promotes the agglomeration of inclusions; the morphologies of the inclusions are mostly blocky, and some are distributed in long strips. After rare earth treatment during the RH refining process, the number of inclusions with sizes of 1.0~3.5 μm in the experimental steel is increased, and the average size of the inclusions is 2.66 μm. In addition, the number of inclusions larger than 4 μm in the specimens increases due to the collision and growth of inclusions caused by the RH circulation. After rare earth treatment during the tundish process, the number of micro inclusions with sizes of 1.0~2.5 μm in the specimen steels decreases, while the number of inclusions larger than 5 μm increases. The size distribution of micro inclusions in hot-rolled sheets after rare earth treatment was studied using TEM (transmission electron microscopy). In the specimens without rare earth, the content of micro inclusions (≤1 μm) is 51,458.2/mm2 and the average size is 0.388 μm. In the specimens with rare earth added, the content of micro inclusions (≤1 μm) is 24,230.2/mm2 and the average size is 0.427 μm. Compared to sheet produced by the original process, the iron loss of the 0.35 mm finished experimental sheet is reduced by 0.068 W/kg, and the magnetic induction is increased by 0.007 T. The iron loss of the 0.50 mm finished experimental sheet is reduced by 0.008 W/kg, and the magnetic induction is increased by 0.004 T. After rare earth treatment, the average size of micro inclusions increases and the magnetic properties are obviously improved. [ABSTRACT FROM AUTHOR]

Rare-earth (RE) oxide embedded ordered mesoporous silica have been successfully prepared via a solution impregnation method. The structure and physical property of the nanocomposites (NCs) were studied by low-angle X-ray diffraction, Transmission Electron Microscopy (TEM), Photoluminescence (PL) and magnetic measurement. The NCs exhibited the room temperature 5D0 → 7Fj transition emission due to the presence of Eu3+ ions. Also the NC system showed a room temperature weak ferromagnetism due to the large oxygen vacancy present in the system. Photoluminescence, magnetic property and large surface area, make these NCs ideal multi-functional materials, which will have potential applications in the field of bio-medicine and drug-delivery. These kinds of nanocomposites are promising candidates for fabrication of various environment friendly smart devices. [ABSTRACT FROM AUTHOR]

The first-principle calculation method based on the density functional theory (DFT) in combination with the LDA+U algorithm is employed to study the electronic structure and magnetic properties of Co/Mn co-doped ZnO nanowires. Special attention is paid to the optimal geometric replacement position, the coupling mechanism, and the magnetic origin of Co/Mn atoms. According to the simulation data, Co/Mn co-doped ZnO nanowires of all configurations exhibit ferromagnetism, and substitution of Co/Mn atoms for Zn in the (0001) inner layer brings nanowires to the ground state. In the magnetic coupling state, the obvious spin splitting is detected near the Fermi level, and strong hybridization effects are observed between the Co/Mn 3d and O 2p states. Moreover, the ferromagnetic ordering forming Co2+-O2−-Mn2+ magnetic path is established. In addition, the calculation results suggest that the magnetic moment mainly takes its origin from the Co/Mn 3d orbital electrons, and the size of the magnetic moment is related to the electronic configurations of Co/Mn atoms. Therefore, a realistic description of the electronic structure of Co/Mn co-doped ZnO nanowires, obtained via LDA+U method, shows their potential for diluted magnetic semiconductor materials. [ABSTRACT FROM AUTHOR]

Thermal treatment induced phase transition of LaAlO 3 in glass and its influence on glass structure and dielectric, magnetic, and Faraday rotation properties were characterized through various techniques such as nuclear magnetic resonance, X-ray neutron diffraction, transmission electron microscopy, X-ray photoelectron microscopy, vibrating-sample magnetometer, and electron paramagnetic resonance. Cubic LaAlO 3 nanocrystals were synthesized and incorporated into lead-tellurite glasses, after crystallization treatment at 380 °C for 2 h, 14-17 nm-cubic LaAlO 3 nanocrystals were changed to 14-27 nm-rhombohedral LaAlO 3 perovskite due to the temperature-induced viscosity and strain in the melt. The phase transition of LaAlO 3 nanocrystals in glass matrix was verified through versatile techniques in terms of the octahedral AlO 6 distortion, SAED patterns, changes of lattice parameters calculated by Rietveld refinement, and coordination number changes of AlO 6 by NMR and XPS techniques. The modification to the glass structure was yielded by phase transition through converting TeO 4 →TeO 3 , AlO 6 →AlO 4, BO 4 →BO 3 , and producing non-bridging oxygen. In addition, the energy band gap and density of states of glass after phase transition was calculated through Density functional theory (DFT) simulation. Glass doped with 10% LaAlO 3 exhibited a promising dielectric constant and good thermal stability due to the phase transition induced polarizability, and improved optical and magnetic performance which is promising for photonics device applications. [ABSTRACT FROM AUTHOR]

Magnetic refrigeration by utilizing the magnetocaloric effect of magnetic solid materials has been expected to be a green energy technology. In this work, double perovskite oxides Gd 2 NiMn 1- x Ti x O 6 (0 ≤ x ≤ 1) were successfully synthesized via the traditional solid-state reaction method. Structural, magnetic and cryogenic magnetocaloric properties of the prepared samples were experimentally investigated. The magnetic measurements indicate that the ferromagnetic phase is progressively suppressed by Ti substitution in Gd 2 NiMn 1- x Ti x O 6 owing to the dilution effect of nonmagnetic Ti4+ with 3 d 0 configuration. In addition, the two vital parameters of magnetic entropy change and refrigeration capacity for magnetocaloric properties have been calculated and analyzed. The values of the maximum magnetic entropy change and refrigeration capacity show a similar change regularity, which decrease firstly from 23.33 J kg−1 K−1 (334.68 J kg−1) at x = 0 to 13.70 J kg−1 K−1 (226.07 J kg−1) at x = 0.4, and then increase significantly to 27.57 J kg−1 K−1 (360.02 J kg−1) at x = 1 under Δ H = 6 T. A possible mechanism for the effect of Ti substitution on the magnetic and magnetocaloric properties of Gd 2 NiMn 1- x Ti x O 6 has been proposed. The present work indicates that Gd 2 NiMn 1- x Ti x O 6 could be important candidates for magnetic refrigeration application. [ABSTRACT FROM AUTHOR]

Based on first-principles calculations, this work reports the effect of doping sites of several different depths on the electromagnetic properties of 1.2-nm-sized ZnO quantum dots. The model doping concentration is 2.222%, close to the optimal concentration of 2% for nanoparticles. Under the effect of p-d hybridization, internal sites are more likely to be doped by Mn2+. The intermediate doping sites are beneficial to obtain stable structures and good electromagnetic properties for the ZnO-based diluted magnetic quantum dots. As the doping site changes, the system exhibits different magnetic properties: ferromagnetism (FM) or anti-ferromagnetism (AFM). These differences are the result of a combination of system structure and doping site depth. Studying the doping sites of Mn-doped ZnO quantum dots is of great reference value for developing low-dimensional transition metal-doped oxides. [ABSTRACT FROM AUTHOR]

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FeSiCr/epoxy resin soft magnetic composites with powder modification by silane coupling agent were fabricated for injection molding. The flowability, wettability, and magnetic properties of the composites were studied by a melting index detector, contact angle tester, vibrating sample magnetometer, inductance/capacitance/resistance (LCR) meter, and an alternating current magnetic measurement system. The cross-section morphologies of the composite rings were observed by scanning electron microscopy (SEM). The results showed that the silane coupling agent obviously improved the flowability of the composites due to the increase of compatibility and combination between epoxy resin and the FeSiCr particles. At the same powder content, the permeability and density decreased slightly in the coupled samples compared with those without modification. The core losses of both coupled and uncoupled samples with 90–93 wt.% contents followed Steinmetz's law with the frequency exponent equivalent to 1.128–1.179 in the broad frequency range of 100–2000 kHz. By curve fitting and loss separation, the excess loss and its frequency exponent (α) of the composite samples with 93 wt.% powder content were determined. The influence of the coupling agent on the flowability and magnetic properties is also discussed. [ABSTRACT FROM AUTHOR]

Summary: The polycrystalline SrFe12O19 samples deeply substituted up to at.67% by Al3+, Ga3+, In3+, Co3+, and Cr3+ cations with a high configurational mixing entropy were prepared by solid-phase synthesis. Phase purity and unit cell parameters were obtained from XRD and analyzed versus the average ionic radius of the iron sublattice. The crystallite size varied around ∼4.5 μm. A comprehensive study of the magnetization was realized in various fields and temperatures. The saturation magnetization was calculated using the Law of Approach to Saturation. The accompanying magnetic parameters were determined. The magnetic crystallographic anisotropy coefficient and the anisotropy field were calculated. All investigated magnetization curves turned out to be nonmonotonic. The magnetic ordering and freezing temperatures were extracted from the ZFC and FC curves. The average size of magnetic clusters varied around ∼350 nm. The high values of the configurational mixing entropy and the phenomenon of magnetic dilution were taken into account.

Summary: Maintaining the completeness of cargo and achieving on-demand cargo release during long navigations in complex environments of the internal human body is crucial. Herein, we report a novel design of magnetic hydrogel soft capsule microrobots, which can be physically disintegrated to release microrobot swarms and diverse cargoes with almost no loss. CaCl2 solution and magnetic powders are utilized to produce suspension droplets, which are put into sodium alginate solution to generate magnetic hydrogel membranes for enclosing microrobot swarms and cargos. Low-density rotating magnetic fields drive the microrobots. Strong gradient magnetic fields break the mechanical structure of the hydrogel shell to implement on-demand release. Under the guidance of ultrasound imaging, the microrobot is remotely controlled in acidic or alkaline environments, similar to those in the human digestion system. The proposed capsule microrobots provide a promising solution for targeted cargo delivery in the internal human body.

In the present study, the structure, magnetic phase transition, and magnetocaloric performance of Al20Mn20Fe20Co14.5+xCr25.5-x (x = 0, 1, and 2), a series of typical rare-earth-free high-entropy (HE) alloys, were experimentally determined and theoretically analyzed based on first-principle calculation. Ferromagnetic behavior was established and their Curie temperature could be tuned in a wide temperature range, which correlated with Co content; specifically, it increased from 282.8 K for Co14.5Cr25.5 to 345.8 K for Co16.5Cr23.5. In addition, the electronic density of states and magnetic moments associated with each consistent element were analyzed in the HE alloys. Maximum magnetic entropy changes of 1.135, 1.150, and 1.096 J/kgK were obtained for an x of 0, 1, and 2 under a magnetic field change of 5 T. These values are comparable or superior to those of reported 3d metal-based HE alloys. Furthermore, the experimental characterizations and theoretical predications agreed well, which provided an in-depth understanding of the rare-earth-free HE Al-Mn-Co-Fe-Cr alloy system, which is expected to be expanded to other systems in the future.

Due to it has large saturation magnetization (Ms), high magnetocrystalline anisotropy field and high ferromagnetic resonance (FMR) frequency, barium ferrite (BaM) has attracted more and more attentions in the fields of magnetic recording media, permanent magnets and microwave devices. Here, BaM thin films were deposited on Pt/TiO _2 /SiO _2 /Si substrates, and the effect of annealing temperature on the microstructure, magnetic and microwave properties of barium ferrite thin films was investigated in detail. It is found that when the BaM thin film was annealed at 1035 °C, it has good properties. The XRD data provide clear evidence that the BaM thin films have high c-axis orientation, and the Lotgering factor is as high as 0.96. The AFM morphology show that BaM grains are out of the film plane, and they are hexagonal. The magnetic hysteresis curves indicated that both saturated magnetization (4 π Ms), remanence ratio and coercive (Hc) for out of plane increase with increasing Ta first, then decreased, and get the maximum value at 1035 °C. The ferromagnetic resonance (FMR) measurement show that the FMR linewidth is 143 Oe@50 GHz, it means that this this sample has low microwave loss in millimeter wave loss, and the FMR absorption can be tuned by applied magnetic field. These results make sure that this BaM thin film is possible use in millimeter wave devices such as filers, circulators and isolators.

A mononuclear Ni(II) complex, [Ni(HL1)2], (1) and a novel tetranuclear heterometal Mn-Ni complex, [Mn3Ni(L1)4Cl2(EtOH)2], (2) [H2L1 = N-(2-hydroxymethylphenyl)salicylideneimine], have been synthesized and characterized via X-ray crystal structure analyses, infrared spectra, and elemental analyses. The structure analyses revealed that the tridentate ligand, H2L1, coordinates in a facial mode for Ni and a mer mode for Mn, respectively. Complex 2 includes Mn(II)Mn(III)2Ni(II) tetranuclear metal core bridged by μ-phenoxo and μ-alkoxo oxygens. Magnetic measurements for 2 indicate that weak ferromagnetic interactions (JMn(III)Ni(II) = 2.23, JMn(III)Mn(II) = 0.46, JMn(II)Ni(II) = 1.78, and JMn(III)Mn(III) = 0.58 cm−1) dominate in the tetranuclear core. Additionally, in alternating current (AC) magnetic measurements, frequency-dependent out-of-phase responses were observed.

For tailoring the mechanical and magnetic properties of dual-phase high-entropy alloys (HEAs), it is crucial to understand the effect of each phase on the overall properties. In this paper, the effects of individual FCC and BCC phases on the mechanical and magnetic properties of the FeCoNi(CuAl)0.8 HEA are investigated by nanoindentation and first-principles calculations. The nano-hardness of the BCC phase is 8.73 GPa, which is nearly double the 4.60 GPa of the FCC phase, which ascribes to spherical nanoprecipitates that are only observed in the BCC phase leading to precipitation hardening. First-principles calculations on the electronic structure show that calculated saturation magnetization (Ms) of the BCC phase is 0.81 T, higher than 0.77 T of the FCC phase. An approximate yield strength and Ms can be estimated by summing the volume-fraction-weighted contributions from each phase, and are in good agreement with experimental values. It indicates that the overall mechanical and magnetic properties of the dual-phase HEAs can be tailored by tuning the volume fraction of the individual phase. Our findings are helpful to design prospective dual-phase HEAs with both good mechanical properties and soft magnetic performance by adjusting the content of each phase.

The effects of both single- and two-step direct current (DC) annealing procedures on the magnetic properties (including the giant magneto-impedance (GMI)) of glass-coated Co66Fe6Si13B15 amorphous wires were evaluated. For both methods, the GMI ratio initially increased with the current intensity and reached a peak value before declining at higher current intensities. A maximum improvement of the GMI ratio of about five times was obtained for the two-step DC-annealed sample, while that for single-step DC-annealed samples was only 2.44 times. A higher GMI sensitivity was also observed for the two-step DC-annealed wires. The better GMI performance of the two-step DC annealed samples was attributed to the more homogeneously distributed precipitation in the matrix and the ordered circumferential magnetic domains on the surface. The results obtained further imply that DC annealing at a higher current intensity but over a shorter treatment time is a more efficient and energy-saving method for enhancing the GMI performance of Co-based amorphous wires for potential industrial applications. [ABSTRACT FROM AUTHOR]

Tests for low-cycle fatigue in the elastic-plastic deformation region of samples made of 09G2S steel prepared on a 3D laser printer by selective laser Melting (SLM-steel) were carried out. The major hysteresis loops and field dependences of the reversible magnetic permeability were measured. It was found that normalization at 980°C (1 h) reduces the tensile strength of SLM steel 09G2S by 2 times ( MPa) and increases the elongation by almost 6 times (), bringing this steel closer to cast steel 09G2S. The magnetic properties () of cast and SLM-normalized steel before and after cyclic tests are similar. The main changes in these properties of both cast and SLM steel are observed at the initial stage of low-cycle tests; a further increase in the number of cycles (up to the destruction of the test samples) does not lead to any considerable change in them. The nature of the change in the magnetoelastic field determined from the experimental field dependences of reversible magnetic permeability during low-cycle tests for cast and SLM steels is radically different: for cast steel 09G2S, the magnetoelastic field practically does not change with increasing the number of cycles, whereas for steel 09G2S manufactured using selective laser melting, there is a sharp increase in the value of by 30% during the first test cycles that is most likely due to an increase in residual stresses. [ABSTRACT FROM AUTHOR]

In the present study, cobalt–nickel ferrite nanoparticles (CoxNi1-xFe2O4 where x = 0, 0.3, 0.5, 0.7, and 1) have been synthesized by the hydrothermal method assisted by malonic acid. Structural and morphological studies were accomplished by FTIR, XRD, XPS, FESEM, EDAX, and TEM. Structural and morphological studies illustrate single-phase spinel ferrites with monodispersed nanoparticles. Further, the average crystallite size was calculated by Debye–Scherrer's equation. It was found between the ranges 7.9–15.4 nm for cobalt–nickel ferrites with varying cobalt mole fractions. Cobalt–nickel ferrite particles show a non-uniform particle shape which may be a result of its magnetic behavior (particle–particle attraction). Thermal gravimetric analysis was carried out to study the heat treatment process and to obtain the oxide phase. Also, magnetic properties were analyzed by taking the help of VSM. The saturation magnetization of nanoparticles remains within the range of 33.53–77.54 emu/g and coercivity lies between 50.50 and 933.69 Oe, respectively. In our study, a simple hydrothermal synthetic method assisted by malonic acid has been performed. It is quite environmentally friendly, economical and at the same time produces particles with small-size distribution. The synthesized cobalt–nickel ferrite samples are a promising candidate for high-density recording media. [ABSTRACT FROM AUTHOR]

The electronic, magnetic and structural properties of Pd2FeTl compound were investigated in this study. The Vienna Simulation Package program was used to perform calculations, based on DFT and Generalized Gradient Approximation. The lattice parameter of 6.360A0 and its magnetic moment value of 3.063µB/f.u. are calculated. The values for the magnetic moment and lattice parameter were found to be in conformity with those in the literature. As electronic properties and band structures were calculated, also the density of state curves compatible with the band structures were drawn. There is no band gap between the energy bands in terms of Pd2FeTl compound and according to the calculations, this compound has a metallic structure. [ABSTRACT FROM AUTHOR]

High-temperature annealing is a key step for the secondary recrystallization of grain-oriented silicon steel, which has an important effect on the final sharp Goss texture. In this work, the effects of three different annealing atmospheres during high-temperature annealing (100%H2, 25%N2 + 75%H2 and 50%N2 + 50%H2) on the secondary recrystallization microstructure and texture of Fe-3.2%Si-0.055%Nb low temperature grain-oriented silicon steel were analyzed by optical microscopy (OM) and electron back-scattered diffraction (EBSD) techniques, and the magnetic properties of the samples were compared. The results show that when the high-temperature annealing atmosphere is 100%H2, the texture of the grains with secondary recrystallization is mainly <110>//ND orientation, but the grains without secondary recrystallization have a disordered orientation. When the high-temperature annealing atmosphere is 50%H2 + 50%N2, the secondary recrystallization grains present a Goss texture and brass texture. After high-temperature annealing in the 25%N2 + 75%H2 atmosphere, the sample can be fully recrystallized to obtain secondary recrystallization grains; the grain size is relatively uniform and the texture is mainly a Goss texture with a sharp edge. The content of this reaches 93.1%, the magnetic induction B800 is the highest, reaching 1.89 T, and the iron loss P1.7/50 is the lowest, reaching 1.33 W/kg. [ABSTRACT FROM AUTHOR]

The CoFe2O4/La0.7Sr0.3MnO3 composites with the La0.7Sr0.3MnO3 mass ratio of 18% was prepared by solid state reaction method, and the magnetic properties under pressure (P) were studied. As P < 0.21 GPa, the grain spacing was reduced by the pressure, resulting in the simultaneous enhancement of the exchange coupling interaction and the dipole interaction between the grains. The results are as follows: (1) the temperature region (ΔT) in which the exchange coupling dominates in the field-colding magnetization (MFC) curve broadens with the pressure. (2) The MFC value at 10 K, i.e., MFC(10 K) increases with pressure. (3) The difference between the zero-field-colding magnetization (MZFC) as P > 0 and as P = 0 was denoted as ΔMZFC(T); it shows the result of ΔMZFC(T) > 0, i.e., the pressure increases the magnetization. Moreover, the values of ΔMZFC(T) increases with the increase in pressure. As P > 0.21 GPa, ΔT and MFC(10 K) hardly change with the pressure; the ΔMZFC(T) curve approximately coincides; the strength of inter-grain exchange-coupling hardly changes with the pressure. These results show that the 0.21 GPa pressure compresses the grain spacing to the greatest degree, and the magnetic moments between grains or within the grain boundaries were arranged in parallel to the greatest extent. In addition, the paramagnetic-ferromagnetic transition temperature Tc of La0.7Sr0.3MnO3 in the composite changes faster with pressure than the Tc of the single-phase La0.7Sr0.3MnO3 sample does. Finally, the pressure can improve the magnetic performance; specifically, the 0.21 GPa pressure increases the saturation magnetization Ms and the remanence ratio Mr/Ms by 3.5% and 17.9%, due to the contribution of grain boundary magnetization. [ABSTRACT FROM AUTHOR]

Hexagonal Y1 - x Hox Mn0.8 Fe0.2O3 polycrystalline samples were synthesized by high-temperature solid-state reaction method. The effects of Ho3+ doping on microstructure and magnetic properties of YMn0.8 Fe0.2O3 were investigated in this paper. X-ray diffraction (XRD) and Raman spectra (RS) show that all samples are of single-phase hexagonal structure without another impurity phase. When the doping concentration (x) of Ho3+ is lower than 0.15, the lattice constants, unit cell volume and bond length between the Mn--O of the samples decrease with x increasing. The decrease of the lattice constants may be related to the interaction between the Mn3+ / Fe3+ 3d orbital and the Ho3+ 4f orbital, resulting in lattice distortion and electron loss. The displacements of the rare-earth atoms at the A-site relative to the plane and the inclination of the MnO5 bipyramids are suppressed with increasing doping concentration, which is demonstrated by the shift deviations of the rare-earth atoms and the variations of the Raman phonon modes. At the same time, the trimerization of Mn3+ at the B-site is weakened. The magnetic properties of the samples were measured using the superconductor quantum interference device (SQUID). Results show that the antiferromagnetic (AFM) order decreases upon Ho3 + doping, consistent with the reduced superexchange interaction between Mn3+ --O2- --Mn3+. The AFM transition temperature TN decreases. Besides, the magnetization of the samples and the weak ferromagnetic (WFM) order at low temperature are significantly enhanced, which is attributed to the suppressed magnetic resistance behavior of the system and the ferromagnetic order generated by the spin exchange interaction between Ho3+ --O2- --Mn3+. These provide an idea for us to further explore room temperature multiferroic materials. [ABSTRACT FROM AUTHOR]

The composite of yttrium iron garnet (YIG) and erbium iron garnet (ErIG; i.e., ErIG(x)/YIG(1−x) (x = 0.5)) was prepared by facile mechanical blending method. X-ray diffraction study reveals the pure phase formation of YIG, ErIG and ErIG(x)/YIG(1−x). Field-emission scanning electron microscope micrographs were used to calculate grain size of the samples. Impedance analyser was used to study dielectric property of YIG, ErIG and ErIG(x)/YIG(1−x). The composite ErIG(x)/YIG(1−x) has larger values of dielectric constant and lower values of tangent losses ∼0.05 at 1 MHz. Calculated ac conductivity of ErIG(x)/YIG(1−x) composite is low, which implies its resistive nature. The value of coercivity (Hc) is lesser and value of magnetic saturation (Ms) is high for composite as compare to parent YIG and ErIG. The calculated value of microwave operating frequency (ωm) for composite was found to be 4.5 GHz. The good dielectric property, low dielectric losses and enhanced magnetic property of ErIG(x)/YIG(1−x) composite suggest a better option over parent garnet ferrites to be used in microwave devices such as dielectric antennas. [ABSTRACT FROM AUTHOR]

The widespread use of electronic devices leads to Electromagnetic Interference (EMI), which reduces equipment's performance and even threatens human health. Consequently, attempts have been made to develop shields against EMI using magnetic and conductive components. In this study, one of the most industrially prominent polypropylene (PP) nonwoven was converted to an EMI shield through the deposition of conductive polyaniline (PAn) and various magnetic (nano)particles (MPs), such as Fe3O4, CoFe2O4, and MnFe2O4. The preparation of PP composite was ensured by polymerization of the aniline in the presence of different MPs impregnated-PP fabrics. The MPs' crystal structures and magnetic properties, and morphological changes of the PP were revealed by XRD, Vibrating Sample Magnetometer (VSM), and SEM techniques. The EMI shielding property of the fabrics was examined within 30 MHz-3 GHz. Accordingly, the double-coated PP/MnFe2O4/PAn composite showed the highest absorption-dominant attenuation (94.2% at 2.11 GHz) with a 12.4 dB EMSE value. [ABSTRACT FROM AUTHOR]

Hexagonal Y1 - x Hox Mn0.8 Fe0.2O3 polycrystalline samples were synthesized by high-temperature solid-state reaction method. The effects of Ho3+ doping on microstructure and magnetic properties of YMn0.8 Fe0.2O3 were investigated in this paper. X-ray diffraction (XRD) and Raman spectra (RS) show that all samples are of single-phase hexagonal structure without another impurity phase. When the doping concentration (x) of Ho3+ is lower than 0.15, the lattice constants, unit cell volume and bond length between the Mn--O of the samples decrease with x increasing. The decrease of the lattice constants may be related to the interaction between the Mn3+ / Fe3+ 3d orbital and the Ho3+ 4f orbital, resulting in lattice distortion and electron loss. The displacements of the rare-earth atoms at the A-site relative to the plane and the inclination of the MnO5 bipyramids are suppressed with increasing doping concentration, which is demonstrated by the shift deviations of the rare-earth atoms and the variations of the Raman phonon modes. At the same time, the trimerization of Mn3+ at the B-site is weakened. The magnetic properties of the samples were measured using the superconductor quantum interference device (SQUID). Results show that the antiferromagnetic (AFM) order decreases upon Ho3 + doping, consistent with the reduced superexchange interaction between Mn3+ --O2- --Mn3+. The AFM transition temperature TN decreases. Besides, the magnetization of the samples and the weak ferromagnetic (WFM) order at low temperature are significantly enhanced, which is attributed to the suppressed magnetic resistance behavior of the system and the ferromagnetic order generated by the spin exchange interaction between Ho3+ --O2- --Mn3+. These provide an idea for us to further explore room temperature multiferroic materials. [ABSTRACT FROM AUTHOR]

New types of microwave absorption (MA) materials are urgently demanded in military radars and communication satellites working in the frequency of 8–12 GHz (X band) and 12–18 GHz (Ku band). However, it remains a challenge to make a material completely satisfy the MA requirements in the whole frequency bands. Here, two-dimensional (2D) Ti3CNTx nanolayered flakes were produced by HF etching of the Ti3AlCN precursor and exhibited an attractive MA performance in the X and Ku bands. The minimum reflection loss (RL) of Ti3CNTx was −41.36 dB at 11.76 GHz with a sample thickness of 1.94 mm. Meanwhile, an effective absorption band (EAB) of 4.24 GHz (in the frequency range 13.76–18 GHz) was achieved when the sample thickness was 1.5 mm. Spin-polarized density functional theory calculations confirmed that Ti3CNTx possesses magnetic moments. The magnetic moments mainly originate from the severe asymmetric spin of electrons of Ti atoms located between N and functional groups induced by the unpaired electrons of N atoms. The synergetic effects of dielectric loss and magnetic loss mechanisms contribute to the MA performance of Ti3CNTx. 2D nanosheets of Ti3CNTx are a promising candidate for MA applications. [ABSTRACT FROM AUTHOR]

Two new Cu(II) complexes [Cu2(L)2(mb)](ClO4)·0.5H2O (1) and [Cu4(L)4(sq)(H2O)2](ClO4)2·2H2O (2) (HL = 2‐[(2‐morpholine‐4‐yl‐ethylimino)‐methyl]‐phenol); mb = 4‐methyl benzoate; sq2− = C4O42− squarate dianion) have been synthesized and characterized by single crystal X‐ray analysis, electrospray ionization mass spectrometry, and infrared spectroscopic technique. The structural determination showed the Schiff base acting as tridentate ligand coordinating the copper(II) atoms by the phenoxo, imino and morpholine nitrogen donors to give comparable Cu(L) entities in both complexes 1 and 2. Complex 1 is a dinuclear cationic species built by a 4‐methylbenzoate anion coordinating two Cu(L) moieties. The two Cu(II) centers are chemically equivalent exhibiting a distorted square pyramidal geometry. Complex 2 is tetranuclear and it is formed by a centrosymmetric squarate core connected to four Cu(L) complex units to give a cationic complex counterbalanced by perchlorate anions. Of the two independent Cu(II) atoms, Cu1 exhibits a square pyramidal coordination sphere, whereas Cu2 is better described as square planar. The crystal packing of complex 2 shows a polymeric arrangement through H‐bonding. Magnetic measurements show antiferromagnetic coupling in both the complexes. The interaction of complexes with hen egg lysozyme has been investigated by using UV–vis absorption and 2D/3D fluorescence spectroscopic techniques and the calculated values of binding constants, Kbin, are (5.9 ± 0.11) × 104, (17.39 ± 0.04) × 104, and (10.1 ± 0.07) × 104 M−1 for HL, 1, and 2, respectively. [ABSTRACT FROM AUTHOR]

Since the discovery of graphene, various two-dimensional materials with novel properties have attracted more and more attention. Janus two-dimensional materials have asymmetric surface properties. These special structures often have peculiar electrical, magnetic and optical properties, which have become a research hotspot in the field of material science in recent years. In this paper, the structures of Janus two-dimensional materials CrXX'(X/X'= S,Se,Te)(CrSSe, CrSTe, CrSeTe) were built, their electronic, magnetic, optical properties were studied, and the effect of biaxial strain on above properties was studied. In terms of electronic structure, the results show that CrSSe, CrSTe and CrSeTe are metallic and excellent conductors of electrons. Biaxial strain does not change their metallicity, which means their electronic structure has good robustness. In terms of magnetic properties, due to the contribution of unpaired electrons in the 3d orbital of Cr atom, CrXX'(X/X' = S,Se,Te) have long range magnetic ordering. By applying tensile strain, their magnetic moments increase, and by applying compressive strain, their magnetic moments decrease. In addition, CrXX'(X/X' = S,Se,Te) have higher Curie temperature. The Curie temperature of CrSSe is 165 K, that of CrSeTe is 195 K, and that of CrSTe is 310 K, which is above the room temperature. For optical properties, the results show that CrXX'(X/X' = S,Se,Te) have excellent absorption capacity of visible and ultraviolet light, which is about 50% higher than that of typical light absorption material graphene. Their light absorption coefficients can be adjusted by applying strain, compressive strain and tensile strain can move the absorption spectrum to short wave and long wave respectively. In conclusion, this work provides theoretical guidance for the further study of the application of two-dimensional monolayer CrXX' (X/X' = S,Se,Te) in the field of new room temperature spintronic devices. [ABSTRACT FROM AUTHOR]

The electronic structures and magnetic properties of the bulk Fe2 Ge and its (001) surfaces were calculated by the pseudo-potential plane wave method based on the first-principle of density functional theory. Here, two types of the terminated (001) surfaces were considered: Ge(I)-(001) surface and Ge(II)-(001) surface. For the electronic structures, the different types of the Fe2Ge (001) surfaces all show metallic characteristics, which are in agreement with the bulk counterpart. For the magnetism, the Ge atoms are ferromagnetic spin ordering in the bulk and Ge(II)-(001) surface, while the Ge atoms are ferrimagnetic spin ordering in the first layer of the Ge(I)-(001) surface. Moreover, the spin magnetic moment of the Ge atoms in the Ge(II)-(001) surface are better than those of the bulk and Ge(I)-(001) surface. These results are related to the hybridization between the Fe d and Ge p states, which were discussed by analyzing their density of states. [ABSTRACT FROM AUTHOR]

In this paper, the crystal structure, vacancies, magnetoelectric properties and magneto-thermal properties of Gd 1- x Dy x CrO 3 (0 ≤ x ≤ 0.5) samples were reported. In crystal structure analysis, after doping Dy3+, the lattice constant and the grain size of the sample decreases. The results of positron annihilation lifetime study indicates that the overall electron density near defect increases and that appeared as a gradual decreasing trend of τ 2 with Dy3+ concentration. The ferromagnetism of the sample gradually decreased after doping, and the T N (Cr) of the sample decreased systematically with increasing concentration of Dy3+. Moreover, the introduction of Dy3+ inhibited the magneto-electric coupling and weakened the magneto-thermal properties of the samples. This result reveals the effect of Dy3+ doping on the structure, magnetic properties, magnetothermal and dielectric properties of GdCrO 3. • Dy3+ doping decreases the antiferromagnetic transition temperature of the sample. • Magnetoelectric coupling gradually disappears in Dy3+ doped samples. • The magneto-thermal properties of Dy3+ doped samples are gradually weakened. [ABSTRACT FROM AUTHOR]