Magnetocaloric properties of shape-dependent nanostructured Gd2O3 oxide particles

Single-phase Gd2O3 nanostructures with different morphologies, such as nanoparticles, nanorods, nanospheres, and nanoplates, were synthesised. Gd2O3 1D nanorods and 2D nanoplate architectures were prepared via the hydrothermal method, while 3D hollow nanospheres were synthesised via homogeneous precipitation. The magnetic and magnetocaloric properties of Gd2O3 nanostructured particles were studied as functions of temperature and field. The material demonstrated typical paramagnetic behaviour in the measured temperature range of 3-300 K. The magnetic entropy change (-Delta S-M) was determined from the magnetic isotherms measured in the 3-38 K temperature range in the field up to 5 T. The maximum change in magnetic entropy (Delta S-M(max)) value 11.2 J kg(-1) K-1 for the nanoplate, 9.4 J kg(-1) K-1 for the nanorod, 9.2 J kg(-1) K-1 for the nanosphere, and 10.7 J kg(-1) K-1 for the nanoparticle sample was observed at temperature 5 K for the magnetic field of 5 T. Owing to large Delta S-M(max), these Gd2O3 nanostructured particles would be considered promising materials for magnetic refrigeration at cryogenic temperatures.

Automated summary

Single-phase Gd2O3 nanostructures with various morphologies were synthesized, including nanoparticles, nanorods, nanospheres, and nanoplates. The magnetic and magnetocaloric properties of these nanostructures were studied at different temperatures and magnetic fields. The maximum change in magnetic entropy (Delta S-M(max)) values were observed at 5 K and 5 T for the nanoplate (11.2 J kg(-1) K-1), nanorod (9.4 J kg(-1) K-1), nanosphere (9.2 J kg(-1) K-1), and nanoparticle (10.7 J kg(-1) K-1) samples. These Gd2O3 nanostructures show potential for magnetic refrigeration at cryogenic temperatures due to their large Delta S-M(max) values.