Source abstract
Abstract
Magnetic refrigeration, resulting from the magnetocaloric effect of a material around the magnetic phase-transition temperature, is a topic of great interest as it is considered to be an alternate energy solution to conventional vapor-compression refrigeration. The viability of a magnetic refrigeration system for magnetic cooling can be tested by exploiting materials in various forms, from bulk to nanostrucutres. In this study, magnetocaloric properties of self-assembled Mn3O4-La(0.7)Sr(0.3)MnO3 nanocomposites, with varying doping concentrations of Mn3O4 in the form of nanocrystals embedded in the La(0.7)Sr(0.3)MnO3 matrix, are investigated. The temperatures corresponding to the paramagnetic-to-ferromagnetic transitions are higher, and the values of change in magnetic entropy under a magnetic field of 2 T show an enhancement (highest being ∼130%) for the nanocomposites with low doping concentrations of Mn3O4, compared to that of pure La(0.7)Sr(0.3)MnO3 thin films. Relative cooling power remain close to those of La(0.7)Sr(0.3)MnO3. The enhanced magnetic phase-transition temperature and magnetocaloric effect are interpreted and evidenced in the framework of interfacial coupling between Mn3O4 and La(0.7)Sr(0.3)MnO3. This work demonstrates the potentiality of self-assembled nanostructures for magnetic cooling near room temperature under low magnetic fields.
Source: openalex_inverted_index · Quality: baseline
Affiliations
Department of Physics, National Cheng Kung University, Tainan 701, Taiwan
Department of Materials Science and Engineering, National Chiao Tung University, HsinChu 300, Taiwan
School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
Department of Physics, Durham University, Durham DH1, United Kingdom
Institute of Physics, Academia Sinica, Taipei 105, Taiwan
Funding
Ministry of Science and Technology, Taiwan