Large reversible magnetocaloric effect in TbCoC2 in low magnetic field

Abstract

A large reversible negative magnetic-entropy change ⌬S M has been observed in TbCoC 2 , accompanied by a second-order phase transition at 28 K. The maximum value of −⌬S M is 15.3 J kg −1 K −1 at 30 K for a magnetic-field change from 0 to 5 T, with the refrigerant capacity of 354 J kg −1. In particular, also the large −⌬S M max of 7.8 J kg −1 K −1 , is obtained for a small field change from 0 to 2 T. The large reversible ⌬S M and the high reversible refrigerant capacity in low magnetic field indicate that TbCoC 2 may be a promising candidate for magnetic refrigeration at low temperatures.

Magnetic Properties and Magnetocaloric Effect in Layered NdMn_1.9Ti_0.1Si₂

“…3, the -∆S M values (from increasing and decreasing field) have a small different respectively. The changes in magnetic entropy for NdMn 1.9 Ti 0.1 Si 2 ferromagnetic ordering temperatures are indicated in this paper as calculated from decreasing applied fields in order to satisfy the suitability of different experimental and related analytical approaches to establish the isothermal entropy change [18] [19,20] in the temperature region below 100 K; particularly important is the very small field hysteresis losses of the compound.…”

Reversible magnetocaloric effect and refrigeration capacity enhanced by two successive magnetic transitions in DyB2

“…Moreover, a giant MCE around room temperature has been observed in several first-order magnetic transition (FOMT) systems such as Gd 5 (Si 2 Ge 2 ) [8], LaFe 11.4 Si 1. 6 [9] MnFeP 0.45 As 0.55 [10] and MnAs-based compounds [11,12]. However, for applications, a reversible MCE based on a SOMT is much more promising due to less thermal hysteresis and a relatively wide working-temperature window.…”

“…This effect has been attracting much attention due to potential application in magnetic refrigeration. Since a large MCE was observed in gadolinium, the MCE has been extensively investigated of many magnetic materials that exhibit a second-order magnetic transition (SOMT) [4][5][6][7]. Moreover, a giant MCE around room temperature has been observed in several first-order magnetic transition (FOMT) systems such as Gd 5 (Si 2 Ge 2 ) [8], LaFe 11.4 Si 1.…”

Magnetic Properties and Magnetocaloric Effect in Layered NdMn1.9V0.1Si2

“…Never the less it is noted that the MCE values of -∆S M ~ 21.4 J kg -1 K -1 for NdMn 1.9 V 0.1 Si 2 at 0-5 T applied field is higher than with MCE values for other materials with small hysteresis that exhibit transitions in the temperature region below 100 K. These materials include: TbCoC 2 [14] (-∆S M =15 J kg -1 K -1 at 28K), GdCoAl [15](-∆S M =10.4 J kg -1 K -1 at 100K) and TbCoAl [15] (-∆S M =10.5 J kg -1 K -1 at 70K), all of which -in common with NdMn 1.9 V 0.1 Si 2 -importantly very small field hysteresis losses. The magnetic entropy change, -∆S M (T,B) has also been derived from heat calorimetric measurements of the field dependence of the heat capacity using the expression [2,16,17]:…”