Multicaloric Cryocooling Using Heavy Rare-Earth Free La(Fe,Si)₁₃-Based Compounds.

Area of Science:

• Materials Science
• Thermodynamics
• Sustainable Energy Technologies

Background:

• Renewable energy transition necessitates energy-efficient technologies like magnetocaloric cooling.
• Current magnetocaloric materials rely on critical rare-earth elements, limiting global sustainability.
• Cryogenic gas liquefaction requires advanced, environmentally friendly cooling solutions.

Purpose of the Study:

• To explore the potential of multicaloric cooling using a La$_{0.7}$Ce$_{0.3}$Fe$_{11.6}$Si$_{1.4}$ multiferroic material.
• To mitigate the reliance on resource-critical materials in magnetocaloric refrigeration.
• To investigate the use of combined isotropic pressure and magnetic field stimuli for inducing phase transitions.

Main Methods:

• Utilized a multicaloric cooling concept combining isotropic pressure and magnetic field.
• Employed La$_{0.7}$Ce$_{0.3}$Fe$_{11.6}$Si$_{1.4}$, a low-cost, low-criticality multiferroic material.
• Measured isothermal entropy changes across a wide temperature range (190 K to 30 K).

Main Results:

• Achieved maximum isothermal entropy changes of up to -28 J (kg K)$^{-1}$.
• Demonstrated the feasibility of multicaloric cryocooling in the specified temperature range.
• Explored the unique properties and challenges of this novel cooling approach.

Conclusions:

• Multicaloric cooling provides an additional degree of freedom for tailoring phase transition properties.
• This approach can lead to energy-efficient and environmentally friendly gas liquefaction.
• Designed-for-purpose, noncritical multiferroic materials are key for sustainable cryogenic technologies.