Studies on the structural, magnetic and electrochemical properties of GdMn1−xFexO3 (x = 0, 0.1 and 0.2) perovskite compounds

Abstract

The tunable physical properties of the rare earth manganite GdMnO₃ hold significant promise for different applications. Herein, we systematically investigate the modification of the structure, magnetic properties, and electrochemical performance of GdMn_1−xFe_xO₃ (x = 0, 0.1, and 0.2). The X-ray diffraction (XRD) patterns of GdMn_1−xFe_xO₃ (x = 0, 0.1, and 0.2) confirm the existence of a pure orthorhombic structure with the space group P_bnm. Rietveld refinement establishes the existence of an O′-type orthorhombic structure independent of x. With an increase in x, the lattice volume and the Jahn–Teller (J–T) distortion factor decrease. The reduction in lattice volume is attributed to the presence of Mn⁴⁺ ions accompanied by oxygen vacancies, as confirmed via XPS and XANES studies, and the decrease in the J–T distortion factor is reflected through a reduction in the intensity of the asymmetric stretching band located at 487 cm⁻¹ in Raman spectroscopy studies. Temperature-dependent magnetization measurements reveal that the Néel temperature, T_N, considerably enhances from ∼42 K at x = 0 to ∼84 K at x = 0.2, which is essentially due to improved antiferromagnetic interactions involving Mn/Fe–O–Mn/Fe. The spin dynamics of GdMn_1−xFe_xO₃, discussed using phenomenological models, such as Néel-Arrhenius, Vogel–Fulcher, and Power law models, reveal a spin-glass nature. Further, the feasibility of using GdMn_1−xFe_xO₃ for potential supercapacitor applications has been confirmed due to a 2-fold increase in the specific capacitance owing to enhanced oxidation–reduction reactions between the electrode and electrolyte. We conclude here that GdMn_1−xFe_xO₃ is a potential multifunctional material.