Enhancement of giant refrigerant capacity in Ho1-xGdxB2 alloys (0.1 ≤ x ≤ 0.4)

2020/11/25 by Pedro Baptista de Castro, Kensei Terashima, Takafumi D Yamamoto +10
Materials Science · Physics and Astronomy · #Chemical engineering #Magnetic Properties of Alloys #Magnetic and transport properties of perovskites and related materials #Magnetic field #Magnetic refrigeration #Magnetization #Materials science #Metallurgy #Nanotechnology #Physics #Rare-earth and actinide compounds #Refrigerant #Thermodynamics #cond-mat.mtrl-sci

paper · pdf · doi:10.1016/j.jallcom.2021.158881

12 pages, 4 figures and 1 table

arxiv created 2020/11/25 · openalex created_date 2020/12/07 · openalex publication_date 2021/01/22 · arxiv updated 2021/04/15 · openalex updated_date 2026/08/05

Abstract

Intending to optimize the giant magnetocaloric properties of HoB₂, we synthesized and magnetocalorically characterized Ho_1-xGd_xB₂(0.1 ≤ x ≤ 0.4) alloys. We found out that Gd enters stoichiometrically and randomly into the Ho site, leading to a Vegard-type structural change. The addition of spherical S^7/2 Gd³⁺ moments prompts an enhancement in Curie temperature, a reduction in peak value of the magnetic entropy change while still being relatively high, and a broadening of the magnetic entropy change curves. The overall influence is a relatively high refrigerant capacity and relative cooling power, and an extension of the thermal working range to higher temperatures; thus, electing Ho_1-xGd_xB₂(as potential candidates for cryogenic refrigeration applications.

Citations

• On a generalised approach to first and second order magnetic transitions
• Recent developments in magnetocaloric materials