Tailoring the optical bandgap and magnetization of cobalt ferrite thin films through controlled zinc doping

Abstract

In this report, the tuning of the optical bandgap and saturation magnetization of cobalt ferrite (CFO) thin films through low doping of zinc (Zn) has been demonstrated. The Zn doped CFO thin films with doping concentrations (0 to 10%) have been synthesized by ultrasonic assisted chemical vapour deposition technique. The optical bandgap varies from 1.48 to 1.88 eV and saturation magnetization varies from 142 to 221 emu/cc with the increase in the doping concentration and this change in the optical and magnetic properties is attributed to the change in the relative population of the Co2+ at the tetrahedral and octahedral sites. Raman study confirms the decrease in the population of Co2+ at tetrahedral sites with controlled Zn doping in CFO thin films. A quantitative analysis has been presented to explain the observed variation in the optical bandgap and saturation magnetization.

Synthesis, structural investigation, dielectric and magnetic properties of Zn2+-doped cobalt ferrite by the sol–gel technique

“…16 Recently the researchers are doing enormous study on Zn doped cobalt ferrites in terms of their optical properties alongside with dielectric and magnetic properties. [17][18][19] In the present work, we used to investigate the synthesis, structural, electrical and magnetic properties of Zn substituted cobalt ferrite Co 1Àx Zn x Fe 2 O 4 (x ¼ 0:0, 0.2, 0.4, 0.6) prepared by sol-gel method. In this method both exothermic and self-propagating auto combustion redox reaction occurred to form xerogel.…”

Correlating the size and cation inversion factor in context of magnetic and optical behavior of CoFe2O4 nanoparticles

“…This behavior is general characteristics of ferrites nanoparticles and is observed by number of researchers. 21,22,28,46 The saturation magnetization of these nanoparticles are 52 AE 2, 66 AE 2, 70 AE 2 and 81 AE 2 emu g À1 for annealing temperature of 300, 500, 700 and 900 C (Fig. 5a).…”

“…XRD patterns of these nanoparticles were rened using FullProf program based on Rietveld analysis. 22 The space group Fd3m was assumed, with the 8a, l6d cation sites and 32e O sites all fully occupied. 14 Values of goodness of factor (GOF) obtained for these rened patterns vary from 1.1 to 1.5.…”

“…Thus, distribution of metal ions play an important to control magnetic behavior that provide an opportunity to optimize this material for particular applications. [19][20][21] Additionally, optical behavior of this material is no less important, 14,22,23 however, it's size dependence and correlation with metal ion distribution remains obscure.…”

High Curie temperature and enhanced magnetoelectric properties of the laminated Li0.058(Na0.535K0.48)0.942NbO3/Co0.6 Zn0.4Fe1.7Mn0.3O4 composites

“…Simple Li-doped KNN is still a good candidate for use in the lead-free piezoelectric ceramics2425. Compared with the classical cobalt ferrite (CFO), Zn and Mn doped cobalt ferrite (Co 0.6 Zn 0.4 Fe 1.7 Mn 0.3 O 4 ) possess enhanced ferromagnetic and magnetostrictive properties2627. Hence, Li 0.058 (Na 0.535 K 0.48 ) 0.942 NbO 3 (LKNN) was chosen to be the ferroelectric phase and Co 0.6 Zn 0.4 Fe 1.7 Mn 0.3 O 4 (CZFM) with 0.3 wt% Li 2 CO 3 was used as the magnetic phase.…”