Synthesis and studies of Zn-doped LaMnO_3+dnanoperovskite by sol–gel processing

Abstract

Nanoparticles with high surface area of LaMn 1−x Zn x O 3+d (LMZ) (0.0 ≤ x ≤ 0.38) were synthesized by the Pechini-type polymerizable complex technique based on in situ polyesterification between citric acid (CA) and ethylene glycol (EG). Heating at 90 • C of a mixed solution of CA, EG, H 2 O, and nitrates of La, Mn, and Zn, gave a polymeric resin. The polymeric resin or citrate-derived gel was preheated at 450 • C for 2 h to give a powdered precursor of LMZ. The final heat treatment of the powdered precursor was done in static air at a temperature range 700-800 • C for 6 h. After calcinations of the dried gels, the products were characterized by the X-ray powder diffraction technique, Fourier transform infrared analysis, and scanning electron microscopy. The products are of considerable interest both for utilization as catalysts and for their exceptional magnetotransport properties.

Preparation, characterization and luminescent properties of europium oxide doped nano LaMn0·9Zn0·1O3+d by sol-gel processing

“…Europium doped LaMn 0⋅9 Zn 0⋅1 O 3+d were prepared by Pechini sol-gel method (Alemi et al 2008) employing the corresponding metal nitrates and Eu 2 O 3 weighed and dissolved in acid to form europium nitrate. Then aqueous solutions of metal nitrates with nominal atomic ratios La : Eu : Mn : Zn = (1 -x): x : 0⋅9 : 0⋅1, with x = 0⋅00, 0⋅1, 0⋅2, and 0⋅32 were mixed together in de-ionized water to give a concentrated solution.…”

“…Various methods have been tested to synthesize lanthanum manganite, LaMnO 3+d , including the conventional solid-state reaction (Inaguma et al 2006), co-precipitation (Philip andKutty 2000), sol-gel (Gaudon et al 2002;Alemi et al 2008), hydrothermal synthesis (Zenati et al 2005) and molten salts reactions.…”