Neodymium (Nd3+)-doped yttrium iron Garnet (YIG) nanoparticles, with compositional variation of NdxY3−xFe5O12 (0.0 ≤ x ≤ 3.0), were prepared by co-precipitation method. The prepared nanoparticles were characterized using TGA, XRD, TEM, SEM, EDX, and FTIR. The calcination temperature was chosen according to the maximum decomposition temperature (˃ 810 °C) achieved in TGA. XRD confirmed the successful phase formation, at the chosen sintering temperature (1100 °C), of Garnet for x < 3.0 (cubic Ia3d symmetry), after which the orthoferrite phase NdFeO3 at x = 3.0 (orthorhombic Pnma symmetry) was formed. The incorporation of Nd3+ increased the lattice parameters (12.3833–12.5020 A), porosity (34.127–39.549%) and crystallite size (82.66–129.99 nm). Agglomerated, distorted, and irregularly shaped nanoparticles were observed in TEM and SEM with the elemental composition confirmed by EDX, inconsistency with the proposed NdxY3−xFe5O12. The FTIR analysis revealed the characteristic bands at 657, 600, and 565 cm−1 with Nd3+ doping concentration between 0.0 and 1.5. These bands disappeared at x = 3.0, where the orthoferrite phase of NdFeO3 dominated. UV–Vis spectroscopy revealed the semiconducting behavior of the prepared samples with energy gaps ranging between 2.89 and 3.02 eV. A broad emission band was observed, in the range 500–550 nm, in the PL spectra of all the prepared samples in agreement with the calculated band energies. The transport properties were studied by DC conductivity measurements and analyzed by the Arrhenius plots, from which two activation energies were determined for each sample. The magnetic properties, investigated by VSM, showed that isovalent substitution of Y3+ by Nd3+ dramatically influenced room temperature parameters, such as saturation magnetization, coercivity, and remanence magnetization.

Effects of neodymium substitution on the structural, optical, and magnetic properties of yttrium iron garnet nanoparticles

Intelligent Control of Microwave Heating Temperature for Smart City Road Deicer Considering Ambient Temperature

Yttrium iron garnet (YIG) nano powders have been successfully synthesized by a chemical co-precipitation plus microwave heating method. The particle sizes of the synthesized YIG powders ranged from 15 nm to 30 nm. Their heating behaviors indicated that small YIG nano crystallites in the synthesized powders started to melt and form liquid phase at a low temperature about 947°C. By using the synthesized powders as the starting materials, the dense YIG ceramics were sintered at the temperature of about 1050–1100°C, which was much lower than the sintering temperature for the powder derived from traditional solid reactions. The liquid phase from melting of small particles promoted the diffusion and re-crystallization, resulting in the low temperature sintering of YIG ceramics.

Microwave-Assisted Synthesis of Yttrium Iron Garnet Nano Powders for Low Temperature Sintering

Disclosed is a Nd-Fe-Bferrite composite flexible magnet prepared by modifying Nd-Fe-B magnetic powder with modifying liquid, preparing the modified Nd-Fe-Bferrite composite flexible magnet with rub binder and ferrite, and preparing the modified Nd-Fe-Bferrite composite flexible magnet with rubber binder and ferrite. The modified liquid is composed of epoxy resin, aminopropyltriethylsilane and dioctyl phthalate. A magnetic powder modifying liquid is use for modifying the surface of the Nd-Fe-B magnetic powder, as the ferrite is taken as the second fil magnetic powder phase, the use amount of the Nd-Fe-B magnetic powder is reduced, the corrosion resistance of the final flexible magnet is improved, and a composite flexible magnet with excellent magnetic properties, good mechanical propertiesand good corrosion resistance is obtain.

Maofang Ren

Papers

Microwave-Assisted Synthesis of Yttrium Iron Garnet Nano Powders for Low Temperature Sintering

NdFeBferrite composite flexible magnet and preparation method thereof