Title :

Large magnetocaloric effect due to spin-glass behavior in the (Mn_1/3R_2/3)₂(Mn_1/3Sb_2/3)₂O₇ pyrochlore series

Author(s) :

Solana-Madruga, E. [Auteur]
Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] [UCM]
Dos Santos-Garcã­a, A. J. [Auteur]
Universidad Politécnica de Madrid [UPM]
Ritter, C. [Auteur]
Institut Laue-Langevin [ILL]
Arevalo Lopez, Angel [Auteur]
Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181
Avila-Brande, D. [Auteur]
Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] [UCM]
Urones-Garrote, E. [Auteur]
Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] [UCM]
Sã¡ez-Puche, R. [Auteur]
Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] [UCM]

Journal title :

Solid State Sci.

Abbreviated title :

Solid State Sci.

Volume number :

150

Pages :

107499

Publication date :

2024-05-06

ISSN :

1293-2558

English keyword(s) :

Magnetocaloric effect
Magnetic refrigeration
Cryo-cooling
Hydrogen energy
Spin-glass
Pyrochlore

HAL domain(s) :

Chimie/Chimie inorganique

English abstract : [en]

The synthesis, structural characterization and magnetic properties of the (Mn1/3R2/3)2(Mn1/3Sb2/3)2O7 pyrochlore series are detailed herein. The R3+ (Rare earth) and Sb5+ cations occupy the A and B sites respectively, due ...
Show more >The synthesis, structural characterization and magnetic properties of the (Mn1/3R2/3)2(Mn1/3Sb2/3)2O7 pyrochlore series are detailed herein. The R3+ (Rare earth) and Sb5+ cations occupy the A and B sites respectively, due to their charge/size ratio. Mn is found to be located in a 1/3 ratio in both positions with selective oxidation state due to size restrictions. Mixed valence in Mn2+/Mn3+ was confirmed from EELS spectroscopy. According to their geometric frustration and R3+-Mn2+/Sb5+-Mn3+ disorder, spin glass behavior is observed from dc and ac magnetic susceptibility data and no long-range magnetic order could be observed from NPD data down to 1.5 K. The magnetic entropy variation calculated from field dependent magnetization curves reveals large magnetocaloric effect (MCE) for these compounds, suggesting its relation to the dynamics of the frozen state. These values reach up to ΔSM ∼20.7 J/kgK for the Rdouble bondGd sample, which is comparable to other materials with large MCE induced by FM order. This renders these materials competitive in magnetic refrigeration and opens the path for new enhanced magnetocaloric materials exploiting this mechanism.Show less >

Language :

Anglais

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

Université de Lille
CNRS
Centrale Lille
ENSCL
Univ. Artois

Collections :

• Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181

Research team(s) :

Matériaux inorganiques, structures, systèmes et propriétés (MISSP)

Submission date :

2024-05-18T21:08:12Z
2024-05-31T08:12:35Z