An evaluation of the impact of Ca substitution on the structural and magnetic properties of GdMnO3 ceramics. Issue 5 (1st April 2020)

• Record Type: Journal Article
• Authors: Chen, J.; Dai, H.Y.; Wang, M.M.; Ye, F.J.; Li, T.; Xu, M.S.; Chen, Z.P.
• Is Part Of: Ceramics international. Volume 46:Issue 5(2020)
• Page Start: 6360
• Page End: 6367
• Publication Date: 2020-04-01
• Subjects: Gd1-xCaxMnO3 -- Structure -- Magnetic properties -- Defects; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2019.11.112
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: To investigate the effects of structural modulation induced by Ca substitution on the magnetic properties of GdMnO3 systems, Gd1- x Ca x MnO3 ( x = 0.00–0.30) multiferroic ceramic samples were prepared via a solid-state reaction. The XRD, Raman, backscattered electron images results indicated that all of the synthesized compounds formed single-phase structures, without other detectable impurity phases. Ca 2+ ions had fully incorporated into the lattice position of the GdMnO3, resulting in structural distortion. XPS results indicated that Mn 4+ ions were introduced in all of the samples, while oxygen vacancies were introduced in the x > 0.10 samples. SEM images showed that the microstructure of the prepared samples was dense, and the grain size was approximately a few microns and changed with the amount of Ca substitution. Positron annihilation lifetime spectroscopy revealed that large amounts of cation vacancies were present in the Gd1- x Ca x MnO3 ceramics; the vacancies concentration obviously changed as the Ca content increased. Magnetic properties measurements showed that Ca substitution obviously modified the low-temperature magnetic behaviors of the Gd1- x Ca x MnO3, and the appropriate substitution amount of Ca improved the magnetic properties due to Mn 4+ ions in GdMnO3 system introduced by Ca substitution. The investigations demonstrated that the evolution of magnetic properties was closely associated with the concentration of cation vacancies and Mn 4+ ions in the Gd1- x Ca x MnO3 samples.