Studies on characteristic properties of superparamagnetic La 0.67 Sr 0.33−x K x MnO 3 nanoparticles

Large magnetocaloric effect near room temperature in $${\mathbf{L}\mathbf{a}}_{0.67}{(\mathbf{S}\mathbf{r},\mathbf{K}/\mathbf{P}\mathbf{b})}_{0.33}{\mathbf{M}\mathbf{n}\mathbf{O}}_{3}$$ manganite nanomaterials

“…The quality of the refinement is confirmed by the fitting parameter, v 2 , which is obtained in the range of 1.02-1.15. In our previous papers, more detailed study on the crystal structure of these compositions has been reported [20,24]. The observed crystallographic behavior is found to be in good agreement with others [19].…”

“…1a-c. The data were analyzed using the Rietveld refinement technique [24,36] with the help of FullProf software. The obtained results are shown in the same figures, which show an excellent agreement in the observed (I obs ) and calculated (I cal ) diffraction profiles with no unindexed peaks.…”

“…According to the literature survey, there are several methods to synthesize the perovskite compounds. The most commonly used chemical methods are solid-state synthesis [32,33], co-precipitation [34], sol-gel [20,24], hydrothermal [35], etc. For this paper work, the sol-gel method was used for synthesizing the powder samples of LSMO, LSPMO, and LSKMO.…”

“…Out of different perovskite manganites, La 0:67 Sr 0:33 MnO 3 (LSMO) has a large T C of 370 K [18]. An enhancement of its T C as well as magnetization occurs by the substitution of divalent (e.g., Pb 2þ , Ca 2þ ) [19][20][21] and monovalent (e.g., K 1þ , Na 1þ ) [22][23][24] elements in (La, Sr) site. There are few other reports on LSMO compounds, which show maximum magnetic entropy change (DS max M ) between 2:03 [25] to 5:15 [18] J/kg K under l 0 H ¼ 5 T at T C ¼ 375 K. Vadnala et al [26] have reported that due to the doping of Eu 3þ in the (La, Sr) site of LSMO manganites, DS M increases from 3.88 J=kgK (for x ¼ 0:0 at T C ¼ 357K) to 5.03 J=kgK (for x ¼ 0:3 at T C ¼ 296KÞ under the field of 6 T. For the similar compositions, Dhahri et al have found that DS max M (under 5T magnetic field) increases from 4.06 J=kgK (for x ¼ 0:1, at T C ¼ 296KÞ to 4.26 J=kgK (for x ¼ 0:2, at T C ¼ 263KÞ [27].…”

High entropy induced structural stabilization, anisotropy transition and magnetization enhancement effect in La2Co17

“…4(a) and (b), respectively. (La 1/4 Pr 1/4 Nd 1/4 Sm 1/4 ) 2 Co 17 shows ferromagnetic characteristics, and its magnetizing process follows a Langevin model 31 at 5 K and a Brillouin model 32 at 300 K, as listed in eqn (5) and (6):where M , N , μ , H , k B , T , and J correspond to the magnetization, atomic number, atomic magnetic moment, applied magnetic field, Boltzmann constant, temperature, and quantum number, respectively. The fitted magnetizing parameters of (La 1/4 Pr 1/4 Nd 1/4 Sm 1/4 ) 2 Co 17 are listed in Table 3.…”