Role of nickel substitution in the structural, magnetic properties, and magnetocaloric effect in La0.67Ba0.22Sr0.11Mn0.95Ni0.05O3 sample

This paper presents a depth study of structural, magnetic, magnetocaloric effects, and critical behavior of the La 0.67 Ba 0.22 Sr 0.11 Mn 0.95 Ni 0.05 O 3 manganite compound. This material was synthesized using the solid–solid method. The crystallographic study shows that our compound crystallizes in a Pnma orthorhombic structure. The magnetic measurements M (T) show that our material has a transition from the ferromagnetic (FM) state to the paramagnetic (PM) state with increasing the temperature. Arrott plots ( μ 0 H M vs. M 2 ) show that our compound presents a second-order transition. The magnetic entropy change (−∆S M ) was determined by Relying on the Maxwell relation. The obtained results prove that our compound is a promising material which can be used in magnetic refrigeration application, operating over a wide range of temperatures. In addition, the magnetocaloric properties have been investigated using a phenomenological model. Finally, the estimated critical exponents values β, γ, and δ using through various techniques are comparable to those predicted by the mean-field model. The magnetic interaction nature in our samples is described by the calculation of exchange distance J(r).