ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Structural, photocatalytic, electromagnetic properties of rare-earth metal Gd-doped Mg nanoferrites synthesized by citrate gel auto-combustion method

Nakiraboina Venkatesh, D. Ravi Kumar, Shyamsunder Goud, Syed Ismail Ahmad, P. Veerasomaiah, and D. Ravinder

Department of Chemistry, Dr. B. R. Ambedkar Degree College, Baghlingampally, Hyderabad, India

E-mail: d.ravi397@gmail.com

Received: 20 October 2022  Accepted: 2 January 2023

Abstract:

Gadolinium-substituted magnesium nanoferrites with composition, MgGd_xFe_2−xO₄ (X = 0.0–1.0 with 0.025 variations), have been synthesized by citrate gel auto-combustion method. The effect of Gd³⁺ substitution on the structural, photocatalytic, electrical and magnetic of Mg nanoferrites was investigated. XRD, SEM, FTIR, UV–vis, VSM, and dielectric transport measurements were employed to investigate the structural, optical, magnetic, and electrical properties of the synthesized materials. Crystalline sizes, lattice parameters, the volume of the unit cell, and X-ray densities of samples were calculated using the XRD analysis method. The crystalline size obtained was in the range of 15–19 nm determined by Scherrer’s formula. FTIR spectroscopy revealed the formation of spinel structure showing two signature absorption bands, nearby 400 cm⁻¹ and higher wave number at near 600 cm⁻¹, at octahedral and tetrahedral positions, respectively. PL spectroscopy at 400 nm region peaks observed and exhibited fluorescence character. The photocatalytic activity of synthesized samples was analyzed with methylene blue and acid red, and pure Mg ferrite shows high degradation activity which contains low crystalline size. Sample changes from hard to soft magnetic materials could be revealed from VSM studies. The nanoferrites' frequency-dependent AC conductivity (ac) increased as a function of temperature. With increasing frequency, dielectric properties such as dielectric constant and dielectric loss (tan δ) decreased. The results of dielectric investigations show that dielectric dispersion occurs between Fe²⁺ and Fe³⁺ ions due to the hopping mechanism of electrons.

Keywords: Mg–Gd nanoferrites; XRD; Photocatalytic activity; VSM; Electrical studies

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-02664-z

Chemical Papers 77 (5) 2749–2767 (2023)