https://doi.org/10.1140/epjp/i2016-16010-2
Regular Article
Magnetocaloric effect in 
(with x = 0.1 , 0.2 and 0.3)
1
Laboratoire de Physico-Chimie des Matériaux Minéraux et leurs Applications, Centre National de Recherches en Sciences des Matériaux, B.P. 95, 2050, Hammam-Lif, Tunisia
2
Laboratoire des Sciences des Matériaux et de l’Environnement, Département de chimie, Faculté des Sciences de Sfax, 3000, Sfax, Tunisia
3
Institut Européen des Membranes, Université de Montpellier II, Montpellier, France
* e-mail: n_rammeh@yahoo.fr
Received:
11
May
2015
Accepted:
23
November
2015
Published online:
14
January
2016
The present paper is aimed to analyze the effects of sodium substitution on the magnetic entropy change between 
and 
polycrystalline samples. Evaluation of the potential magnetocaloric effects is sought through identifying the magnetic entropy change 
, which was basically determined from the magnetic field dependences of magnetization at different temperatures 
near 
. Interestingly, the substitution of a small amount of Na in nanocrystalline samples (with 
, 0.2 and 0.3) reduced the maximum magnetic entropy 
from 2.2 J kg-1K-1 (for to 0.8 Jkg-1K-1 (for 
for a field change 
T. The relative cooling power (RCP) decreases with increasing Na content reaching 53.13J kg^-1 for ( T), respectively.
© Società Italiana di Fisica and Springer-Verlag Berlin Heidelberg, 2016
