Magnetocaloric properties of hydrogenated Gd, Tb and Dy

0520941 - FZÚ 2020 RIV NL eng J - Journal Article
Chzhan, V.B. - Tereshina, I. S. - Tereshina-Chitrova, Evgenia - Burkhanov, G.S. - Politova, G.A. - Drulis, H.
Magnetocaloric properties of hydrogenated Gd, Tb and Dy.
Journal of Magnetism and Magnetic Materials. Roč. 470, Jan (2019), s. 41-45. ISSN 0304-8853. E-ISSN 1873-4766
R&D Projects: GA ČR GA16-03593S
Institutional support: RVO:68378271
Keywords : rare-earth metals * hydrogenation * magnetocaloric effect * Curie temperature * Neel temperature
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 2.717, year: 2019
Method of publishing: Limited access
https://doi.org/10.1016/j.jmmm.2017.11.128

The influence of hydrogen on magnetocaloric properties of three high purity heavy rare earths (R), gadolinium, terbium and dysprosium is studied. Hydrogenation procedure is performed using high purity hydrogen in a Sievert-type apparatus. In addition to the main α-RHx phase (where x is the hydrogen concentration), appearance of the second phase RH2 or its traces is detected in nearly all hydrogenated samples. In the samples where the main α-RHx phase prevails and only traces of the dihydride phase are found, the magnetocaloric effect (MCE) remains of the same magnitude as in the hydrogen-free samples. With the increase of hydrogen concentration (and with a corresponding increase of the RH2 phase content), the MCE values decrease. Only Gd samples demonstrate the increased Curie temperatures related to the increase of exchange interactions in the Gd-Gd pairs. The Néel temperatures of Tb and Dy retain their values after hydrogenation.
Permanent Link: http://hdl.handle.net/11104/0305616