Electrical and magnetic properties of ε-Fe3N nanoparticles synthesized by chemical vapor condensation process

Preparation of ε-Fe(Si)3N Powder Using a Salt Bath Nitriding Reaction and a Study on the Soft Magnetic Properties of the Powder

“…The vibration is a saturation magnetization of about ±1 emu/g, and the maximum amplitude increase of the saturation magnetization is 8.8%. In the range of 400 to 600 K, the saturation magnetization decreases from 141.29 to 102.40 emu/g with increasing temperature, which is obviously superior to that of Fe 3 N powders [20,21].…”

Dielectric behavior of Bi–Fe3O4 nanocomposite and Fe3O4 nanoparticles prepared via mechanochemical processing

“…4 for both samples the variation of log(ρ AC ) with respect to log f measured at the Verwey transition temperature (120 K) and temperatures lower than 120 K is presented. A peak can be seen around 2 kHz at 120 K and temperatures lower than that, which is attributed to the Verwey transition [29][30][31][32]. Above the Verwey transition temperature (T v ), a thermally activated hopping process describes the electronic conduction [29][30][31][32].…”

“…While the decrease in ε′ with frequency is a natural phenomena due to the fact that any species contributing to polarizability is bound to show lagging behind the applied field at higher frequencies. Koops gave the phenomenological theory for the dielectric dispersion in ferrites at low frequencies [31,32]. He interpreted the result by considering the dielectric material as an inhomogeneous medium of a Maxwell-Wagner type.…”

Nanoscale Metastable ε-Fe3N Ferromagnetic Materials by Self-Sustained Reactions

“…30−36 For example, chemical vapor condensation in the Fe(CO) 5 + NH 3 system produces ε-Fe 3 N particles with sizes of 10−40 nm. 30,31 Thermal treatment of ferric nitrate and gelatin mixtures in nitrogen also forms ε-Fe 3 N. 32 In situ synchrotron X-ray diffraction suggests that FeO forms first at ∼500 K, which then converts to ε-Fe 3 N at ∼800 K, followed by an Fe 3 N → Fe 3 C transformation at 850 K. 33 A mixture of Fe(CO) 5 vapor and Ar/NH 3 gas was passed through a synthetic oil containing a surfactant maintained at 450 K to obtain ε-Fe 3 N magnetic fluids. 34,35 An amorphous material obtained by low temperature (195 K) reaction of sodium with iron(II) bromide in liquid ammonia was annealed at 573 K to obtain ε-Fe 3 N nanoparticles.…”

“…Reactive sputtering and chemical vapor deposition are the two primary methods to fabricate ε-Fe 3 N thin films. − Phase purity of the films, however, is a concern, as other iron nitride phases readily form during deposition. Chemical vapor condensation, sol–gel, liquid ammonia reduction, or electrospraying techniques are the most frequently used methods for preparation of ε-Fe 3 N nanoparticles. − For example, chemical vapor condensation in the Fe­(CO) 5 + NH 3 system produces ε-Fe 3 N particles with sizes of 10–40 nm. , Thermal treatment of ferric nitrate and gelatin mixtures in nitrogen also forms ε-Fe 3 N . In situ synchrotron X-ray diffraction suggests that FeO forms first at ∼500 K, which then converts to ε-Fe 3 N at ∼800 K, followed by an Fe 3 N → Fe 3 C transformation at 850 K .…”