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Cu-Doping Induced Structural Transformation and Magnetocaloric Enhancement in CoCr2O4 Nanoparticles
Ming-Kang Ho1,2, Yun-Tai Yu1, Hsin-Hao Chiu1,2
1Department of Physics, National Dong Hwa University, Hualien 974301, Taiwan.
Copper doping transforms CoCr2O4 nanoparticles
Area of Science:
- Materials Science
- Solid State Physics
- Nanotechnology
Background:
- Spinel ferrites are crucial for magnetic applications.
- Tuning properties of CoCr2O4 nanoparticles is key for advanced materials.
- Understanding structure-property relationships in doped nanomaterials is essential.
Purpose of the Study:
- To investigate the effect of Cu2+ doping on Cu_xCo_1-xCr_2O_4 nanoparticles.
- To analyze structural, magnetic, and magnetocaloric property changes.
- To explore potential applications in magnetic refrigeration.
Main Methods:
- Solution combustion synthesis for nanoparticle preparation.
- X-ray diffraction and Raman spectroscopy for structural analysis.
- Magnetic measurements and Arrott plot analysis for magnetic and phase transition characterization.
Main Results:
- Cu doping induced a structural transformation from cubic spinel to trigonal corundum.
- Increased Cu content led to enhanced ferrimagnetism and higher Curie temperatures (up to 140.2 K).
- Significant enhancement in magnetocaloric effect (MCE) observed, with 20% Cu doping yielding -ΔSM = 2.015 J/kg-K and RCP = 58.87 J/kg.
Conclusions:
- Cu doping effectively tunes the magnetostructural properties of CoCr2O4 nanoparticles.
- The modified nanoparticles exhibit promising characteristics for low-temperature magnetic refrigeration.
- This study highlights a viable strategy for developing advanced magnetic materials.
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