• Correa, Eduardo
• Hijazi, Hussein
• Moffat, Thomas
• Kasaei, Leila
• Rus, Eric

Abstract

<jats:p>Pt<jats:sub>1-x</jats:sub>Ni<jats:sub>x</jats:sub> (x = 0.25 to 0.92) thin films were examined for possible application as magnetic thermometers. The alloys were prepared by potentiostatic electrodeposition from aqueous chloride-based solutions in the presence and absence of 0.5 mol dm<jats:sup>−3</jats:sup> B(OH)<jats:sub>3</jats:sub>. Alloy composition was controlled by the deposition potential with the Ni concentration increasing towards more reducing potentials. Films with x &gt; 0.45 were ferromagnetic with the magnetization at 300 K increasing with nickel content. Magnetization vs temperature (M vs T) at 8 kA m<jats:sup>−1</jats:sup> (100 Oe) showed an increase in the Curie temperature from less than 200 K to above 400 K for the alloys investigated. For films deposited at potentials &gt;−0.6 V vs the saturated calomel electrode (SCE), boric acid had negligible effect on the magnetization at the maximum applied field in M vs H measurements. In contrast, for depositions at more reducing potentials &lt;−0.6 V vs SCE the presence of boric acid resulted in diminished magnetization. This effect was attributed to elevated incorporation of oxygen (up to ∼4 atomic %), along with boron incorporation of about 400 μmol mol<jats:sup>−1</jats:sup>.</jats:p>

Topics

• nickel
• thin film
• Oxygen
• laser emission spectroscopy
• Boron
• electrodeposition
• magnetization
• alloy composition
• Curie temperature