Large magnetic entropy change near room temperature in the LaFe11.5Si1.5H1.3 interstitial compound

The LaFe 11.5 Si 1.5 H 1.3 interstitial compound has been prepared. Its Curie temperature T C (288 K) has been adjusted to around room temperature and the maximal magnetic entropy change (|Δ S |~17.0 J·kg -1 ·K -1 at T C ) is larger than that of Gd (|Δ S |~9.8 J·kg -1 ·K -1 at T C =293 K) by ~73.5% under a magnetic change from 0 to 5 T. The origin of the large magnetic entropy change is attributed to the first-order field-induced itinerant-electron metamagnetic transition. Moreover, the magnetic hysteresis of LaFe 11.5 Si 1.5 H 1.3 under the increase and decrease of the field is very small, which is favourable to magnetic refrigeration application. The present study suggests that the LaFe 11.5 Si 1.5 H 1.3 compound is a promising candidate as a room-temperature magnetic refrigerant.