Magnetic phenomena at the atomic scale were discovered in the early twentieth century, whereas the discovery of the first known magnetic material (Fe3O4) revolutionized the field of magnetism. The magnetic properties of a material depend on temperature, the applied magnetic field, and pressure. A change in these variables will result in the existence of two or more forms of magnetism. Ferroand ...

It is difficult to fabricate high-purity amorphous FeCo alloys by traditional physical methods due to their weak glass forming ability. In this work, the fully amorphous FeCo nanoalloys with high purity and good stability have been prepared by a direct chemical reduction of Fe2+ and Co2+ ions with NaBH₄ as the reducing agent and polyvinylpyrrolidone (PVP) as the surfactant. The morphologies, su...

Nuclear magnetic resonance (NMR) spectroscopy is one of the most powerful experimental tools to probe the local atomic order of a wide range of solid-state compounds. However, due to the complexity of the related spectra, in particular for amorphous materials, their interpretation in terms of structural information is often challenging. These difficulties can be overcome by combining molecular ...

The effect of Cu addition on the soft magnetic properties of Fe­Zr­Si amorphous alloy was investigated by X-ray analysis, TEM observation, and B-H curve tracer. As a melt-spun amorphous ribbon sample was annealed above the crystallization onset temperature, very fine ¡-Fe particles smaller than 315 nm were precipitated and uniformly distributed in an amorphous matrix. Cu addition to Fe­Zr­Si am...

The discovery of improved physical and mechanical properties of amorphous and nanocomposite metallic materials respect to their crystalline counterparts [1], has led to an increasing interest and research activity in the study of these materials during the last two decades. The possibility of tailoring amorphous metallic alloys at cooling rates of 1-100 K/s [2], enables these structurally metas...

For crystalline materials, the microscopic origin of plasticity is well understood in terms of the dynamics of topological defects. For amorphous materials, the underlying structural disorder prevents such a description. Therefore identifying and characterizing the microscopic plastic events in amorphous materials remains an important challenge. We show direct evidence for the coexistence of re...

Recent work shows that nanoparticulate and amorphous molybdenum and tungsten sulfide materials are active catalysts for hydrogen evolution in aqueous solution. These materials hold promise for applications in clean hydrogen production technologies. In this perspective, the syntheses, structures and catalytic activities of nanoparticulate MoS2 and WS2, incomplete cubane-type [Mo3S4] 4+ and amorp...

objective(s): this paper describes coating of magnetite nanoparticles (mnps) with amorphous silica shells.   materials and methods: first, magnetite (fe3o4) nps were synthesized by co-precipitation method and then treated with stabilizer molecule of trisodium citrate to enhance their dispersibility. afterwards, coating with silica was carried out via a sol-gel approach in which the electrostati...