Magnetic properties and large cryogenic low-field magnetocaloric effect of HoCo2 nanoparticles without core/shell structure
Source abstract
Abstract
The HoCo(2) nanoparticles are found to be stable in air without any shell protection. The HoCo(2) nanoparticles display superparamagnetic properties between their blocking temperature of 40 K and Curie temperature of 78 K. The magnetic-entropy change increases with decreasing temperature at a certain magnetic-field change, which is ascribed to the competition between the Zeeman energy and thermal-agitation energy at low temperatures. A large magnetic-entropy change of 19.4 J kg(-1) K(-1) was found at 7.5 K in an applied-field change from 1 to 7 T, while 6.1 J kg(-1) K(-1) was achieved in a low field change of 1 T. HoCo(2) nanoparticles are useful for application of magnetic refrigeration at low temperatures.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Magnetic and transport properties of perovskites and related materials · Physics of Superconductivity and Magnetism · Advanced Condensed Matter Physics
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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