Effect of Yttrium Addition on Structure and Magnetic Properties of Co60Fe20Y20 Thin Films

In this paper, a Co₆₀Fe₂₀Y₂₀ film was sputtered onto Si (100) substrates with thicknesses ranging from 10 to 50 nm under four conditions to investigate the structure, magnetic properties, and surface energy. Under four conditions, the crystal structure of the CoFeY films was found to be amorphous by an X-ray diffraction analyzer (XRD), suggesting that yttrium (Y) added into CoFe films and can be refined in grain size and insufficient annealing temperatures do not induce enough thermal driving force to support grain growth. The saturation magnetization (M_S) and low-frequency alternate-current magnetic susceptibility (χ_ac) increased with the increase of the thicknesses and annealing temperatures, indicating the thickness effect and Y can be refined grain size and improved ferromagnetic spin exchange coupling. The highest Ms and χ_ac values of the Co₆₀Fe₂₀Y₂₀ films were 883 emu/cm³ and 0.26 when the annealed temperature was 300 °C and the thickness was 50 nm. The optimal resonance frequency (f_res) was 50 Hz with the maximum χ_ac value, indicating it could be used at a low frequency range. Moreover, the surface energy increased with the increase of the thickness and annealing temperature. The maximum surface energy of the annealed 300 °C film was 30.02 mJ/mm² at 50 nm. Based on the magnetic and surface energy results, the optimal thickness was 50 nm annealed at 300 °C, which has the highest Ms, χ_ac, and a strong adhesion, which can be as a free or pinned layer that could be combined with the magnetic tunneling layer and applied in magnetic fields.

Ni3Co/G alloy as an earth-abundant robust and stable electrocatalyst for the hydrogen evolution reaction

Nickel-rich nickel–cobalt–graphene alloy was fabricated with outstanding catalytic activity and stability towards HER in alkaline media.

Nanoparticles of Cu–Co alloy derived from layered double hydroxides and their catalytic performance for higher alcohol synthesis from syngas

A series of layered double hydroxides (LDHs) with different Cu/Co ratios were prepared according to the co-precipitation method and used as catalyst precursors for higher alcohol synthesis.

Synthesis, structure and magnetic properties of graphite carbon encapsulated Fe3C nanoparticles for applications as adsorbents

This paper reports the synthesis of graphite carbon encapsulated Fe₃C nanoparticles (Fe₃C/GC NPs).