Ferromagnetic Cr₂Te₃ nanorods with ultrahigh coercivity

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Ferromagnetic materials are crucial for magnetic storage and spintronic devices.
• Controlling the magnetic properties of nanostructures is key to developing next-generation technologies.
• Chromium telluride (Cr2Te3) is a promising material with tunable magnetic characteristics.

Purpose of the Study:

• To synthesize ferromagnetic Cr2Te3 nanorods using a facile one-pot method.
• To investigate the influence of precursor ratios on crystalline phases and magnetic properties.
• To understand the coexistence of hard and soft magnetic phases within nanorods.

Main Methods:

• One-pot high-temperature organic-solution-phase synthesis of Cr2Te3 nanorods.
• Systematic variation of chromium (Cr) and tellurium (Te) precursor molar ratios.
• Characterization of crystalline phases and magnetic properties (e.g., coercivity).
• Density-functional theory (DFT) calculations to verify magnetocrystalline anisotropy.

Main Results:

• Ferromagnetic Cr2Te3 nanorods were successfully synthesized.
• A magnetically hard phase (ordered Cr2Te3) dominates at Cr:Te ratios of 1:1.2–1:1.8.
• A magnetically soft phase, due to disorder, forms under Cr-rich or Te-rich conditions.
• A high coercivity of 9.6 kOe was achieved at a Cr:Te ratio of 1:1.8.
• Coexistence of hard and soft phases within nanorods was observed, exhibiting temperature-dependent magnetic behavior.

Conclusions:

• The synthesis method allows for systematic tuning of Cr2Te3 nanorod magnetic properties.
• Ordered Cr2Te3 nanorods possess significant magnetocrystalline anisotropy, leading to high coercivity.
• The co-existence of distinct magnetic phases within single nanorods presents unique magnetic phenomena.