Electrodeposited Heusler Alloys-Based Nanowires for Shape Memory and Magnetocaloric Applications

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Functional Heusler alloys are critical for advanced magnetic applications.
• Downsizing Heusler alloys into nanowires presents unique challenges and opportunities.
• Previous research on Ni-Fe-Ga nanomaterials showed functional behavior above room temperature.

Purpose of the Study:

• To investigate the fabrication and properties of novel Heusler alloy nanowires.
• To explore the magnetocaloric effect in nanostructured Heusler materials.
• To develop new methods for creating nanodimensional alloys from immiscible elements.

Main Methods:

• Theoretical guidance for nanowire fabrication.
• Electrochemical synthesis of Heusler alloy nanowires.
• Characterization of magnetic properties and phase transitions.

Main Results:

• Fabrication of three novel Heusler alloy nanowires: Ni₆₆Fe₂₁Ga₁₃, Ni₅₈Fe₂₈In₁₄, and Ni₅₀Fe₃₁Sn₁₉.
• Ni₆₆Fe₂₁Ga₁₃ nanowires exhibit a phase transition at ≈375 K with a magnetocaloric response of |ΔS| ≈ 0.12 J·kg^-1·K^-1 at 1 T.
• First-time analysis of magnetic properties for Ni₅₈Fe₂₈In₁₄ and Ni₅₀Fe₃₁Sn₁₉ nanowires.

Conclusions:

• Novel Heusler alloy nanowires can be successfully fabricated using electrochemical methods.
• The Ni-Fe-Ga nanowires demonstrate significant magnetocaloric potential.
• This work introduces a viable approach for nanostructuring alloys from immiscible elements.