Gadolinium-oxide nanoparticles for cryogenic magnetocaloric applications
A Zeleňáková1, P Hrubovčák2,3, A Berkutova2
1Institute of Physics, P.J. Šafárik University, Park Angelinum 9, 04001, Košice, Slovakia. adriana.zelenakova@upjs.sk.
Scientific Reports
|February 11, 2022
Summary
Advanced nanocomposites with gadolinium oxide nanoparticles in a silica matrix show high magnetocaloric effects for cryogenic refrigeration. These materials exhibit significant magnetic entropy changes without thermal hysteresis, making them promising for cooling applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Nanocomposites offer tunable properties by combining different materials at the nanoscale.
- Magnetocaloric materials are crucial for developing efficient solid-state cooling technologies.
Purpose of the Study:
- To investigate the structural and magnetocaloric properties of Gd2O3 nanoparticles embedded in a porous SiO2 matrix.
- To evaluate the potential of these nanocomposites for cryogenic refrigeration applications.
Main Methods:
- Small-angle neutron scattering (SANS) to determine structural characteristics.
- Transmission electron microscopy (TEM) for visualizing nanoparticle distribution and matrix structure.
- Magnetic measurements to quantify magnetocaloric properties, including magnetic entropy change.
Main Results:
- Regular nanopores organized in cubic or hexagonal superlattices were observed.
- Gadolinium oxide nanoparticles (Gd2O3 NPs) were successfully embedded within the porous silica (SiO2) matrix at varying concentrations.
- Extraordinarily high magnetic entropy change values (up to 70 J kg−1 K−1) were achieved at low temperatures.
- Absence of thermal hysteresis was confirmed, indicating efficient magnetic cooling potential.
Conclusions:
- The investigated nanocomposites demonstrate excellent magnetocaloric performance suitable for cryogenic refrigeration.
- The application of scaling laws to magnetic entropy change data provided novel insights into magnetic properties and phase transitions.
- These findings highlight the potential of Gd2O3/SiO2 nanocomposites as advanced materials for next-generation cooling technologies.
