Tunable investigation optical, electrical and magnetic behaviors of Gd3+ substituted lanthanum strontium manganite La0.5-x Sr0.5GdxMnO3 nanopowders facilely synthesized through citrate precursor technique

Abstract

In this report, gadolinium-substituted lanthanum strontium manganite (LSM) system, La0.5Sr0.5-xGdxMnO3 (0.1 ≤ x ≤ 0.4), was synthesized using the citrate precursor processing. The influence of Gd3+ ions content on the structure, optical, electrochemical and magnetic properties of LSM was studied. Evidently, in all compositions, a single monoclinic perovskite phase was obtained after calcination at 1000 °C for 2 h. All powders exhibited crystallite sizes in the range of 25.6–35.1 nm. The formed LSM nanopowders has great optical reflectance of 20–40% from 200 to 800 nm for all substituted samples by Gd3+ ions. Furthermore, the LSM possesses good optical absorbance of 0.65 from 200 to 800 nm. The optical band gap energy was decreased from 2.45 to 1.63 eV by increasing the Gd3+ ions molar ratios from 0.1 to 0.4. Meanwhile, the electrochemical impedance spectroscopy displayed the good results. The ohmic resistance (Rs) and the polarization resistance (Rp) of the electrode were increased by increasing the Gd3+ ions concentration from 0.1 to 0.4. Otherwise, both the ohmic resistance (Rs) and polarization resistance in the doped samples were higher than the pure LSM sample. Finally, the saturation magnetization was increased by increasing Gd3+ ions molar ratios. The saturation magnetization was found to be increased from 1.61 A m2/kg for pure LSM to 28.61 A m2/kg for 0.4 Gd3+ ion substituted LSM sample.