Formation during glycine-nitrate combustion and magnetic properties of YFe1–xNixO3 nanoparticles

The synthesis of FeO3 and YFe1–xNixO3 (x = 0.1; 0.15; 0.2; 0.3; 0.5) nanocrystals was performed under the conditions of a self-propagating wave of glycine-nitrate combustion and their characterization and determination of the effect of Ni2+ doping of yttrium ferrite on the magnetic properties of nanopowders. The technology for the synthesis of yttrium orthoferrite nanoparticles (with and without doping with Ni2+ ions) by the glycine-nitrate combustion method at a ratio of G/N = 1 and 1.5 without adding a gelling agent to the reaction mixture and using ethylene glycol/glycerol is described. For the characterization of nanopowders based on YFeO3, the following were determined: phase composition and crystal structure (X-ray diffraction (XRD) method); size and structure of nanocrystal particles (transmission electron microscopy (TEM)); elemental composition of the samples (local X-ray spectral microanalysis (LXSMA)); magnetic characteristics (field dependences of specific magnetization). Thermal annealing of the synthesized samples at 800°C for 60 min led to the formation of the о-YFeO3 main phase. Undoped samples of yttrium orthoferrite were characterized by a particle diameter in the range of 5-185 nm, depending on the gelling agent used. YFe1-xNixO3 particles had a predominantly round shape with a size of 24 to 31 nm; the non-monotonic dependence of the average particle diameter on the dopant content was revealed: as the amount of dopant added increased, the average crystallite size tended to decrease. Nanopowders of undoped yttrium orthoferrite exhibit antiferromagnetic behaviour of magnetic susceptibility with temperature. The change in the magnetic properties of the nickel-doped YFeO3 nanocrystalline powders was due to the incorporation of Ni2+ into the Fe3+position, which led to the formation of a material with more pronounced soft magnetic properties at a substitution degree of 0.1. Samples with high degrees of substitution (x = 0.15 and 0.3) were also characterized by paramagnetic behaviour at temperatures above 100 K

Simple Synthesis of NdFeO3 Nanoparticles By the Co-Precipitation Method Based on a Study of Thermal Behaviors of Fe (III) and Nd (III) Hydroxides

In this study, a nanostructured NdFeO3 material was synthesized via a simple process of the hydrolysis of Nd (III) and Fe (III) cations in hot water with 5% NaOH as a precipitating agent. According to the results of the thermal behaviors of each hydroxide, either containing Fe (III) or Nd (III), the perovskite type of neodymium orthoferrite NdFeO3 was simply synthesized by annealing a mixture of Fe (III) and Nd (III) hydroxides at 750 °C. The nanostructured NdFeO3 was obtained in spherical granules with diameters of around 30 nm. The magnetic properties of the material were a coercive force (Hc) of 136.76 Oe, a remanent magnetization (Mr) of 0.68 emu·g–1, and a saturation magnetization (Ms) of 0.79 emu·g–1