|Particle dispersion and lattice distortion induced magnetic behavior of La1-xSrxMnO3 perovskite nanoparticles grown by salt-assisted solid-state synthesis|
: 91 : 2020.07.04 00:00
|MATERIALS CHEMISTRY AND PHYSICS|
|Pal, Umapada 2020.05.01|
Particle dispersion and lattice distortion induced magnetic behavior of La1-xSrxMnO3 perovskite nanoparticles grown by salt-assisted solid-state synthesis
Ortiz-Quinonez, JL (Ortiz-Quinonez, Jose-Luis)[ 1 ] ; Garcia-Gonzalez, L (Garcia-Gonzalez, Lorena)[ 1 ] ; Cancino-Gordillo, FE (Enrique Cancino-Gordillo, Francisco)[ 1 ] ; Pal, U (Pal, Umapada)[ 1,2,3 ]
La1-xSrxMnO3 perovskites are of enormous current interest due to their superior magnetoresistance and application as cathode material for solid oxide fuel cells. However, practical applications of these perovskites critically depend on size, composition, and concentration of La3+ vacancies at their surfaces. Here we present the fabrication of size controlled (90-255 nm average size), highly crystalline La1-xSrxMnO3 (x = 0, 0.3, 0.5, and 1) nanoparticles, simply by ball-milling of metal acetylacetonate precursors in NaCl and subsequent air-annealing. The size of the nanoparticles increased in the order LaMnO3+delta < La0.7Sr0.3MnO3. La0.5Sr0.5MnO3 < SrMnO3. While LaMnO3+delta particles remain well dispersed, a fraction of particles containing Sr remains partially interconnected after air-annealing (900 degrees C). A change in site symmetry of the Mn3+-O-6 octahedron promoted by the Jahn-Teller distortion of LaMnO3+delta lattice was detected. Substitution of La3+ ions by Sr2+ increases the ferromagnetic interaction in La1-xSrxMnO3 (x = 0, 0.3, 0.5) nanostructures, increasing their Curie temperature and magnetization (M-s) progressively. Effect of particle dispersion due to Sr2+ incorporation on the lattice and magnetic behavior of the nanostructures is discussed considering the Jahn-Teller distortion and La3+ vacancy induced Mn3+ ion oxidation (to Mn4+) in the lattice.