Critical behaviour and magnetocaloric effect of nano crystalline La0.67Ca0.33Mn1−xFexO3 (x = 0.05, 0.2) synthesized by nebulized spray pyrolysis

Effect of Ni-doping on critical behavior of La0.6Pr0.1Ba0.3Mn1−xNixO3 nanocrystalline manganites

“…In particular, the authors in Refs. [23][24][25][26] show an increase of the critical exponent β and a decrease of γ and δ exponents (same trend as our results) when increasing the transitionmetal content into the Mn site. In most cases, the authors in Refs.…”

“…In most cases, the authors in Refs. [23][24][25][26] On the other hand, we can attribute the increase of the critical exponent  to the reduction of the average grain size which decreases as Ni-content increases [11]. This may be explained, as we mentioned in our previous work [11], to the presence of a nonmagnetic surface layer (which destabilizes the magnetic order) that is more important as the average grain size decreases.…”

“…Eq. (8) The values of the critical exponents of our samples and the theoretical values based on the standard models [7,19], besides some of other manganites [23][24][25][26], are summarized in table 1 for comparison. We can see from table 1 that the values of the critical exponents of our samples are in good agreement with those found in Refs.…”

“…We can see from table 1 that the values of the critical exponents of our samples are in good agreement with those found in Refs. [23][24][25][26] for some transition metaldoped manganites. In these references, it is observed that the critical behavior of samples can be affected by partial replacement of Mn ions by some transition-metals such as Ni, Co, Fe and Cr.…”

Magnetic and magnetocaloric properties of nano-sized La0.8Ca0.2Mn1−x Fe x O3 manganites prepared by sol–gel method

“…Another interesting feature in the MCE plot is its asymmetric shape, especially under high field. Similar behavior is observed in Fe-substituted lanthanum calcium manganite [30]. For comparison, the maximum magnetic entropy change, the Curie temperature, and the relative magnetic cooling efficiency of several manganese perovskites considered useful for room-temperature magnetic refrigerators are summarized in Table 3.…”