Magnetic Microcapsules with Carbon Nanotubes-Fe₃O₄ for Enhanced Solar Thermal Energy Storage

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Phase-change materials (PCMs) are crucial for thermal energy storage.
• Developing multifunctional PCMs with enhanced properties remains a challenge.
• Integrating magnetic responsiveness and photothermal conversion is desirable for advanced applications.

Purpose of the Study:

• To fabricate multifunctional microcapsules for enhanced thermal energy storage and solar-to-thermal conversion.
• To incorporate CNTs-Fe3O4 composite for magnetic properties and improved thermal conductivity.
• To evaluate the photothermal conversion efficiency, latent heat, and cycling stability.

Main Methods:

• Pickering emulsion-templating method combined with in situ interfacial precipitation.
• Fabrication of n-eicosane@CNTs-Fe3O4/CaCO3 core-shell microcapsules.
• Characterization of morphology, structure, thermal properties, and magnetic behavior.

Main Results:

• Successfully synthesized microcapsules with core-shell structure and uniform morphology.
• Achieved high photothermal conversion efficiency (63.85%) and latent heat (131.2 J/g).
• Demonstrated superparamagnetic behavior, enhanced thermal conductivity, and excellent cycling stability (>400 cycles).

Conclusions:

• The developed microcapsules offer a promising solution for solar thermal harvesting and intelligent thermal management.
• The multifunctional design integrates magnetic responsiveness, efficient solar-to-thermal conversion, and high-capacity energy storage.
• This work presents a feasible strategy for advanced phase-change material design.