Effect of Ni substitution on phase transition, crystal structure and magnetic properties of nanostructured YFeO3 perovskite

X-ray Absorption Spectroscopy Study of Iron Site Manganese Substituted Yttrium Orthoferrite

In this work, manganese (Mn)-doped YFeO3, i.e., YFMxO powders with 0 ≤ x ≤ 0.1, was synthesized by a hydrothermal method to study the influences of doping on its structural, morphological, optical, magnetic, and local electrical properties. The experimental results show that all the samples exhibit an orthorhombic structure with space group Pnma. Refined structure parameters are presented. Morphology images show the shape evolution from layered to multilayered with increasing Mn content. Infrared spectra reveal the characteristic vibrations of the obtained YFMxO samples. From the magnetic study, an increased magnetic moment in the range of 0 ≤ x ≤ 0.075 is observed. The Fe and Y K-edge local structure studies indicate that the valency of Fe and Y is mainly found in the trivalent state, which also indicates that the substitution of Mn ions not only affects the nearest neighbor atomic shell of Fe but also affects the nearest neighbor’s local structure of Y atoms. Our results show that the addition of Mn exhibits an evident influence on the local structural and magnetic properties.

Multiferroic, Phonon and Optical Properties of Pure and Ion-Doped YFeO3 Nanoparticles

The magnetic, electric, phonon and optical properties of pure and ion-doped orthorhombic YFeO3 nanoparticles are studied for the first time theoretically. The spontaneous magnetization Ms in YFeO3 decreases with decreasing particle size. Ms is also shape dependent. The magnetization increases by Co and Er ion doping and decreases by Ti doping, which is caused by the different strain which appears in the nanoparticles and changes the exchange interaction constants in the doped states. The phonon energy for the Ag mode ω = 149 cm−1 and their damping decreases or increases with increasing temperature, respectively. Both show a kink near the Neel temperature, TN, which disappears by applying an external magnetic field. The influence of different ion doping on the band gap energy is also discussed. The doping effects can be used for different applications.

Co-Doped NdFeO3 Nanoparticles: Synthesis, Optical, and Magnetic Properties Study

In this work, single-phase nanostructured NdFe_1-xCo_xO₃ (x = 0, 0.1, 0.2, and 0.3) perovskite materials were obtained by annealing stoichiochemistry mixtures of their component hydroxides at 750 °C for 60 min. The partial substitution of Fe by Co in the NdFeO₃ crystal lattice leads to significant changes in the structural characteristics, and as a consequence, also alters both the magnetic and optical properties of the resulting perovskites. The low optical band gap (E_g = 2.06 ÷ 1.46 eV) and high coercivity (H_c = 136.76 ÷ 416.06 Oe) give Co-doped NdFeO₃ nanoparticles a huge advantage for application in both photocatalysis and hard magnetic devices.

Low-Temperature Co-Precipitation Synthesis of HoFeO3 Nanoparticles

In this research, we investigate and discuss the characteristics of HoFeO3 nanoparticles synthesized by the co-precipitation method at low temperature (t° ≤ 4 °C). The single-phase HoFeO3 samples with the orthorhombic structure formed after annealing of the precipitates at different temperatures up to 950 °C. The annealed HoFeO3 nanoparticles have an average crystal size of 10–20 nm (SEM, TEM). UV-Vis spectrum of HoFeO3 sample annealed at 750 °C showed strong UV and Vis absorption with small optical energy gap (Eg = 1.56 eV). In the range temperature of 100–300 K, the HoFeO3 samples showed superparamagnetic behaviour at 5 kOe with high magnetization (Ms = 1.3–2.4 emu/g) and very low susceptibility (χ << 1).

The synthesis of novel heterojunction h-YbFeO3/o-YbFeO3 photocatalyst with enhanced Fenton-like activity under visible-light

A simple solution combustion approach followed by heat treatment was used to successfully synthesize a novel h-YbFeO₃/o-YbFeO₃ nanocrystalline heterojunction with an enhanced photo-Fenton-like activity in the decolorization process of methyl violet.