Influence of Ru-doping on structure, defect chemistry, magnetic interaction and carrier motion of the La1-xNaxMnO3+delta manganite

TL;DR

This study investigates how Ru-doping influences the structure, defect chemistry, magnetic interactions, and carrier motion in La1-xNaxMnO3+delta manganites, revealing improvements in electrical and magnetic properties with specific doping levels.

Contribution

It provides new insights into the effects of Ru-doping on the structural, magnetic, and electrical properties of La1-xNaxMnO3+delta manganites, highlighting the role of oxygen content and Ru oxidation state.

Findings

Ru-doping enhances magnetic transition temperature (TC) and magnetoresistance.

Oxygen content and Ru oxidation state significantly affect material properties.

Ru addition improves electrical conductivity and magnetic behavior in low-doped manganites.

Abstract

In this work we report a structural, electrical and magnetic characterization of the La1-xNaxMn1-yRuyO3+d (LNMRO) system with x = 0.05, 0.15 and y = 0, 0.05, 0.15, also comprising an investigation of the role of the oxygen content on the related redox properties. The experimental investigation has been realized with the aid of X-ray powder diffraction, electron microprobe analysis, thermogravimetry, electrical resistivity and magnetization measurements, and electron paramagnetic resonance. We demonstrate that the effect of ruthenium doping on the studied LNMRO compounds is not only directly related to the Ru/Mn substitution and to the Ru oxidation state but also indirectly connected to the oxygen content in the sample. Our data show that ruthenium addition can improve electrical and magnetic properties of non-optimally (low) cation doped manganites, causing an increase of the TC value and the insurgence of MR effect, as observed for the x = 0.05 and y = 0.05 sample.