Effect of La3+ substitution with Gd3+ on the resistive switching properties of La0.7Sr0.3MnO3 thin films

Abstract

This study demonstrated that the resistive switching voltage of perovskite manganite material could be controlled by A-site cation substitution in “A” MnO3 perovskite manganite structure. A partial substitution of La3+ in La0.7Sr0.3MnO3 with smaller cation Gd3+ induced A-site vacancy of the largest Sr2+ cation with surface segregation of SrOy due to ionic size mismatch, and the induced vacancies reduced migration energy barrier. The operating voltage decreased from 3.5 V to 2.5 V due to a favorable condition for electrochemical migration and redox of oxygen ions. Moreover, surface-segregated SrOy was enhanced with Gd-substitution and the SrOy reduced Schottky-like barrier height and resistive switching ratio from the potential drop and screening effect. The relationship between A-site vacancy generation resulting in surface segregation of SrOy and resistive switching behavior was also investigated by energy resolved x-ray photoelectron spectroscopy, O 1s near edge x-ray absorption spectroscopy, and current voltage measurement.

Effects of annealing on structure and composition of LSMO thin films

“…For the Sr 3d 5/2 spectra, two peaks are observed at ca. 133.3 eV (Sr1) and 131.3 eV (Sr2), corresponding to those in SrO-like secondary phases [31] and perovskite lattice [32][33][34] respectively. Roughly, the Sr1/Sr2 ratio is decreasing from LSMO-0-LSMO-4, indicating more segregation of strontium at higher annealing temperature.…”

Synthesis and ESR Study of Transition from Ferromagnetism to Superparamagnetism in La0.8Sr0.2MnO3 Nanomanganite

“…Magnetic nanoparticles (MNPs) display physical and chemical properties different those found in their corresponding bulk materials. These properties make them attractive in widespread applications such as energy, electronics, sensor designs of all kinds, catalysts, magnetic refrigeration, optics, and in various biomedical applications [1][2][3][4][5][6].…”

Unfolding BOB Bonds for an Enhanced ORR Performance in ABO3‐Type Perovskites

“…Valence band spectra for perovskite oxides doped with different A‐site ions radius are shown in Figure b. It is mainly associated with contributions from the bonding states of Mn 3d–O 2p, O 2p nonbonding states, Mn 3d t 2g states and Mn e g states at ≈6.0, ≈3.2, ≈1.8, and ≈0.5 eV, respectively . It can be found that the increase in BO hybridization will contribute to the shift of O 2p nonbonding states toward the Fermi Level.…”