Impact of Tm³⁺ and Tb³⁺ Rare Earth Cations Substitution on the Structure and Magnetic Parameters of Co-Ni Nanospinel Ferrite

• Main Authors: Munirah A. Almessiere, Yassine Slimani, İsmail A. Auwal, Sagar E. Shirsath, Ayyar Manikandan, Abdulhadi Baykal, Bekir Özçelik, İsmail Ercan, Sergei V. Trukhanov, Denis A. Vinnik, Alex V. Trukhanov
• Format: Article
• Language: English
• Published: MDPI AG 2020-11-01
• Series: Nanomaterials
• Subjects: nanospinel ferrites; rare-earth elements; microstructure; morphology; magnetic features
• Online Access: https://www.mdpi.com/2079-4991/10/12/2384

Tm-Tb co-substituted Co-Ni nanospinel ferrites (NSFs) as (Co_0.5Ni_0.5) [Tm_xTb_xFe_2−2x]O₄(x = 0.00–0.05) NSFs were attained via the ultrasound irradiation technique. The phase identification and morphologies of the NSFs were explored using X-rays diffraction (XRD), selected area electron diffraction (SAED), and transmission and scanning electronic microscopes (TEM and SEM). The magnetization measurements against the applied magnetic field (M-H) were made at 300 and 10 K with a vibrating sample magnetometer (VSM). The various prepared nanoparticles revealed a ferrimagnetic character at both 300 and 10 K. The saturation magnetization (M_s), the remanence (M_r), and magneton number () were found to decrease upon the Tb-Tm substitution effect. On the other hand, the coercivity (H_c) was found to diminish with increasing x up to 0.03 and then begins to increase with further rising Tb-Tm content. The H_c values are in the range of 346.7–441.7 Oe at 300 K to 4044.4–5378.7 Oe at 10 K. The variations in magnetic parameters were described based on redistribution of cations, crystallites and/or grains size, canting effects, surface spins effects, super-exchange interaction strength, etc. The observed magnetic results indicated that the synthesized (Co_0.5Ni_0.5)[Tm_xTb_xFe_2−x]O₄ NSFs could be considered as promising candidates to be used for room temperature magnetic applications and magnetic recording media.