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This paper represents a detailed study of Gd3+ substitutions on Structural, Dielectric, Spectroscopic, Raman, and Photo luminance Properties of Ba 0.4 Sr 0.6 Co 2 Fe 16 O 27 magnetic oxides were prepared using the sol-gel auto combustion method. All of these specimens were sintered at 1100 °C for 5 h. X-ray diffraction analysis (XRD) confirmed the single-phase detection and structural analysis. The lattice parameters a and c show the insignificant behavior 5.893–5.933 Å, and 32.049–32.476 Å with the concentration of gadolinium ions. The crystallite size ranged from 25 to 30 nm, demonstrating a growing tendency as Gd-substitution was enhanced. The discrepancy in the ionic radii of iron (Fe3+) and substituent elements (Gd3+) is the cause of the variation in cell volume and lattice constants. FTIR spectroscopy confirmed the presence of absorption bands (590 and 3000 cm−1) for prepared BaSr-based W-type hexa-ferrites. The vibrational bands of metal oxide ions are responsible for the 590 and 685 cm−1 peaks. The Raman spectrum showed six discrete, brittle peaks: 320, 440, 620, 690, 1300, and 1600 of synthesized nanomaterials—the dielectric constant and dielectric loss increase by substituting the Gd3+ ion. The dielectric parameters and dielectric loss at higher frequencies suggest that the prepared material may be excellent for switching, sensing, and high-frequency applications. [Display omitted] • Gd substituted Ba 0.4 Sr 0.6 Co 2 Fe 16 O 27 were prepared via sol-gel auto technique. • The crystallite size was optimised from 25 to 30 nm. • FTIR evidenced absorption bands (590 and 3000 cm−1) for these materials. • Raman spectra showed six discrete peaks: 320, 440, 620, 690, 1300, and 1600. • These may have potential for switching, sensing, and high-frequency applications. [ABSTRACT FROM AUTHOR]

Laminated metal composites have become a key strategy for the design and manufacture of metal parts with multiple combinations of excellent properties. This paper utilizes the differences in mechanical properties and recrystallization behavior of component metals to prepare a novel 316 L/(316 L-2.5 wt%Gd)/316 L neutron shielding laminated metal composites (LMCs) through composite rolling and solution treatment processes. LMCs have an excellent combination of properties: high strength (tensile strength: 571.36 MPa), sufficient tensile ductility (fracture elongation: 60 %) and high neutron shielding properties (thermal neutron shielding rate: > 90 %). Specifically, compared to the non-composite 316 L-2.5 wt%Gd neutron shielding material, the strength of the hot-rolled LMCs has increased by 2.0 times, and the elongation at fracture has improved by 3.3 times. After solid solution treatment, the elongation of LMCs is further increased, which is 6 times higher than non-composite 316 L-2.5 wt%Gd neutron shielding materials. The specially designed soft-hard matched 316 L/(316 L-2.5 wt%Gd) heterogeneous interfaces achieved good metallurgical bonding, with significant differences in grain sizes and strains. The main reasons for the enhanced strength and plasticity of LMCs are the geometric constraints caused by the layered structure composed of ductile and brittle metallic components, as well as the back-stress strengthening and strain hardening induced by deformation incompatibility at the heterogeneous interface. • 316 L/(316 L-2.5 wt%Gd) heterogeneous interfaces with different grain sizes and obvious differences in strains were constructed. • Heterogeneous structure and interfacial constraints synergistically enhance the strength and plasticity of 316 L/(316 L-2.5 wt%Gd)/316 L laminated composites. • Provides a promising solution to the difficult problem of mutual constraints between neutron shielding properties and mechanical properties. [ABSTRACT FROM AUTHOR]

• In-plane magnetic properties and anisotropy of Tm 3 Fe 5-x Sc x O 12 films were studied. • Tm 3 Fe 4.25 Sc 0.75 O 12 film prepared by LPE is (1 1 1) oriented single crystal structure. • Tm 3 Fe 4.25 Sc 0.75 O 12 film has excellent soft magnetic properties in the (1 1 1) plane. • In-plane anisotropy of Tm 3 Fe 5-x Sc x O 12 films is mainly caused by stress. • In-plane anisotropy of Tm 3 Fe 5-x Sc x O 12 films reduces as Sc3+ substitution decreases. In-plane easily magnetized scandium substituted thulium iron garnet films(Tm 3 Fe 5-x Sc x O 12) with soft magnetic properties have recently attracted attention for fluxgate magnetometer applications. In this paper, thin Tm 3 Fe 5-x Sc x O 12 films were prepared on gadolinium gallium garnet substrates by liquid phase epitaxial(LPE) method. Microstructural properties, composition, magnetic properties and the in-plane anisotropy of the films were discussed. We found that the films turned from tensile stress to compressive stress as the Sc3+ substitution decreased, and the in-plane anisotropy was mainly caused by stress reducing as Sc3+ declined. By analyzing the in-plane magnetic hysteresis loops, the magnetic performance was the best when x = 0.75. Tm 3 Fe 4.25 Sc 0.75 O 12 film had the lowest in-plane coercive field(0.006 Oe) and the highest initial magnetic permeability(3 7 8), which was more beneficial to realize fluxgate magnetometers. [ABSTRACT FROM AUTHOR]

In this paper, we present a green synthesis method that allows the obtained cubic-Gd 2 O 3 :Er3+,Yb3+ nanothermometers without using precursors derived from inorganic acids unlike other traditional methods. The performed TEM/HRTEM images, SAED patterns, and XRD analyses confirm the formation of cubic phase Gd 2 O 3 : Er3+,Yb3+ with average particle size about of 15 ± 1 nm after annealing the nanoscale metal-organic frameworks of gadolinium co-doped with 2% mol Er3+ and 20% mol Yb3+ ions (Gd-BTC:Er3+,Yb3+ NMOF) at 700 °C for 1 h. The process of formation of the Gd-BTC:Er3+,Yb3+ NMOF was also investigated in detail by SEM, XRD, EDS, BET, FT-IR and STA/TGA-DSC techniques. The up-conversion emission of the obtained cubic-Gd 2 O 3 :Er3+,Yb3+ nanothermometers were investigated in the 83–773 K temperature range upon 980 nm excitation. As it was proved the red to green emission intensities ratio of Er3+ ions changes monotonically in the whole analyzed temperature range. The calculated relative sensitivity of the luminescence thermometer based on the 2H 11/2 /4S 3/2 → 4I 15/2 to the 4F 9/2 → 4I 15/2 of the obtained cubic-Gd 2 O 3 :Er3+,Yb3+ nanothermometers reached 0.75%/K at 500 K. Additionally the faster thermal quenching of the 4F 9/2 → 4I 15/2 emission band in respect to the 4F 9/2 → 4I 15/2 of Er3+ results in the thermally induced change of the emission colour from red through yellow to green. Thus the chromatic relative sensitivities reached S Rx = 0.2%/K and S Ry = 0.225%/K at 710 K. Furthermore, the magnetic measurements also proved the soft magnetic property of Gd 2 O 3 :Er3+,Yb3+ with saturation magnetization (J s) reached of 8 emu/g at temperature of 150 K Obtained results confirms the application prospects of the multifunctional cubic-Gd 2 O 3 :Er3+,Yb3+ nanothermometers in the biomedical fields. • A green synthesis method that allows the obtained cubic-Gd 2 O 3 :Er3+,Yb3+ is presented. • A visual luminescent thermometer was presented-change in the chromatic coordinates. • Multimodal luminescent thermometer based on Gd 2 O 3 :Er3+,Yb3+ is demonstrated. [ABSTRACT FROM AUTHOR]

Gadolinium oxyhydride GdHO is a photochromic material that darkens under illumination and bleaches back by thermal relaxation. As an inorganic photochromic material that can be easily deposited by magnetron sputtering, GdHO has very interesting potential applications as a functional material, specially for smart glazing applications. However, the underlying reasons behind the photochromic mechanism – which can be instrumental for the correct optimisation of GdHO for different applications – are not completely understood. In this paper, we rely on the well-established magnetic properties of Gd 3 + to shed light on this matter. GdHO thin films present paramagnetic behaviour similar to other Gd 3 + compounds such as Gd 2 O 3. Illumination of the films result in a reversible increase of the Curie–Weiss temperature pointing to Ruderman–Kittel–Kasuya–Yosida RKKY interactions, which is consistent with the resistivity decrease observed in the photodarkened films. • Gadolinium oxyhydride thin films, deposited by magnetron sputtering, exhibit excellent photochromic properties: transparent films significantly darken reversibly by the action of UV light. • Before illumination, the susceptibility of gadolinium oxyhydride aligns well with that of a paramagnetic material, similar to gadolinium oxide. • In the photo-darkened state, ferromagnetic interactions arise pointing to magnetic interactions via conducting electrons. • Our results align well with the widely accepted hypothesis by which photodarkening in oxyhydrides is caused by the formation of metallic-like domains upon illumination. [ABSTRACT FROM AUTHOR]