Effect of synthesis route on structural, magnetic and magnetocaloric aspects and critical behavior of La0.6Ca0.3Ag0.1MnO3

Abstract

The La0.6Ca0.3Ag0.1MnO3 compound was elaborated using two different methods: solid state (S1) reaction and sol-gel (S2) route. Single-phase compound formation was confirmed by preliminary X-ray structural analysis and all samples crystallized in the orthorhombic system with a Pnma space group. The average crystallite size of conventionally processed sample is significantly large as compared to the Pechini sol-gel sample. The obtained results showed a paramagnetic-ferromagnetic transition in all samples. The Banerjee criterion revealed a second order magnetic transition of all samples. The compound elaborated by sol-gel reaction underwent a larger magnetocaloric effect (MCE). The exhibited large relative cooling power (RCP) of 230.35 J/Kg under 5 T indicated that the La0.6Ca0.3Ag0.1MnO3 compound is a good candidate for magnetic refrigeration application. Moreover, β and γ critical exponents were investigated through modified Arrott plots and Kouvel- Fisher (KF) according to the static magnetic measurements around the temperature transition. Also there are found to follow scaling equation with the magnetization data scaled into two different curves below and above TC, which implies the reliability and accuracy of the exponents. The critical exponents find are comparable to the values theoretical predicted for the tricritical mean-field for both samples.