Magnetic and Mssbauer effect studies of ZnO thin film implanted with iron ions to high fluence

We present the results of magnetic and Mssbauer effect studies of zinc oxide thin film obtained by RF magnetron sputtering and implanted with 40 keV iron ions to a fluence of 1.5?1017 ion/cm2. As-implanted and post-annealed sample shows ferromagnetic properties at room temperature and consists of paramagnetic and ferromagnetic phases according to Mssbauer spectroscopy

Magnetic and Mssbauer effect studies of ZnO thin film implanted with iron ions to high fluence

We present the results of magnetic and Mssbauer effect studies of zinc oxide thin film obtained by RF magnetron sputtering and implanted with 40 keV iron ions to a fluence of 1.5?1017 ion/cm2. As-implanted and post-annealed sample shows ferromagnetic properties at room temperature and consists of paramagnetic and ferromagnetic phases according to Mssbauer spectroscopy

Growth of invar nanoparticles on a grapheme oxide support

Binary nanoparticles, composed of two different metals, attract significant attention because they possess properties not typical for their respective single-component nanoparticles. In the bulk form, iron and nickel form an alloy called invar in which the two metals are mixed in a ratio of Fe : Ni = 2 : 1. In this work, we demonstrate the formation of alloyed nanoparticles of invar, as opposed to the theoretically possible formation of particles from the two individual metals. The formation of the alloyed nanoparticles is conducted in a two-step process: liquid phase impregnation of graphene oxide with the salts of the metals, and subsequent annealing of the as-formed dry composite. Unlike the solution phase reaction conditions, in this approach, the binary nanoparticles are assembled under conditions where the metal atoms are immobilized on the surface of the decomposing graphene oxide, and at temperatures significantly lower than the melting points of the two metals. The structure of the as-grown nanocrystals is investigated by Mössbauer spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The majority of the Fe/Ni nanoparticles are in a magnetically ordered state, and the composite is a soft magnet.4092-409

Iron oxidation state in La0.7Sr1.3Fe0.7Ti0.3O4 and La0.5Sr1.5Fe0.5Ti0.5O4 layered perovskites: Magnetic properties

La0.5Sr1.5Fe0.5Ti0.5O4 and La0.7Sr1.3Fe0.7Ti0.3O4 solid solutions with the layered perovskite structure were synthesized using a solid state method. Structural properties of obtained samples were characterized using X-ray diffraction and X-ray fluorescence analyses. Magnetic properties were investigated using magnetometry, electron spin resonance (ESR) and M¨ossbauer spectroscopy methods. Based on magnetization and ESR measurements it was suggested the presence of Fe4+ ions in addition to trivalent iron ions that was exactly confirmed by M¨ossbauer spectroscopy investigations. Based on all experimental results one can suggest the presence of the electronic phase separation in the investigated samples - the simultaneous existence of the paramagnetic phase and magnetically correlated regions, which form due to the mixed-valence iron ions. So the paramagnetic phase with strong antiferromagnetic correlation exists in both samples, while the second phase is ferromagnetically and ferrimagnetically correlated regions in La0.5Sr1.5Fe0.5Ti0.5O4 and La0.7Sr1.3Fe0.7Ti0.3O4, respectively.109994-1-109994-