The samples of Zn 0.5Cu xMg 0.5-xFe 2O 4 nanoparticle ferrites, with x= 0.0, 0.1, 0.2, 0.3, 0.4 were successfully synthesised. Structural and optical properties were investigated by X-ray Diffraction (XRD), Fourier Transform Infrared spectros-copy (FTIR) and UV-visible spectroscopy. The structural studies showed that all the samples prepared through the Co-precipitation method was a single phase of a face-cantered-Cubic (FCC) spinel symmetry structures with space group (SG): Fd-3m. In the series Zn 0.5Cu xMg 0.5-xFe 2O 4, the lattice parameter was found to be 8.382 Å for x = 0 and was found to increase with copper con-centration. The grain size obtained from the XRD data analyses was found to be in the range of 15.97 to 28.33 nm. The increased in the grain size may be due to the large ionic radius of Mg 2+ (0.86 Å) compared with Cu 2+ (0.73 Å). The FTIR spectroscopy confirmed the formation of spinel ferrite and showed the characteristics absorption bands around 580, 1112, 1382, 1682, 1632 and 2920 cm -1. The energy band gap was calculated for samples were found to be in the range 4.04 to 4.67 eV.
Nanotechnology is considered one of the modern sciences that look for designing the smallest apparatus and it concentrates basically on substituting the particle structures or the atomic parts of the material towards realizing new structures and with the economic cost which should not exceed the raw material [
In this work, Nano-ferrite samples of Zn0.5CuxMg0.5-xFe2O4 were synthesised using co-precipitation method. The structural and optical properties were studied using X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR) and UV-Visible spectroscopy. The main purpose is to study the effect of copper substituted magnesium in the Zn0.5CuxMg0.5-xFe2O4 Nano-ferrites.
The samples Zn0.5CuxMg0.5-xFe2O4 ferrites nano-crystalline powder with compositions (x = 0.0,0.1,0.2,0.3,0.4) were prepared using high purity (Sigma,98%) of zinc nitrate [Zn(NO3)2∙6H2O(96%)], magnesium nitrate [Mg(NO3)2(99%)] copper nitrate [Cu(NO3)2∙3H2O(99%)] Ferric nitrate [Fe(NO3)2∙9H2O(98%)] and Sodium hydroxide 96% were used as primary components. A Specified amount of Oleic acid was added to the solution as surfactant and coating material. The solution of Fe(NO3)3∙9H2O, 0.4 M (25 ml), Mg(NO3)2∙6H2O, 0.2 M (25 ml), Cu(NO3)2∙3H2O, and Zn(NO3)2∙6H2O were first mixed and then slowly added 3 molarities of NaOH. The PH of the solution was constantly monitored as the NaOH solution was added. The reactant was constantly stirred using magnetic stirrer unit a pH level of (11-12) [
X-ray diffraction (XRD) data collected by Shimadzu 6000 X-ray diffract meter with Cu-ka radiation of a wavelength of l = 1.5406 Å. At room temperature, with a nickel filter operating at 40 KV, 40 mA the data collected for the 2θ in 0.02-step size and five-second count time in 20˚ - 80˚ range. The MDI jade 0.5 programs used for the XRD date analysis. The crystallite size (D) calculated by Scherer equation [
At room temperature, the transmittance mode investigated for the sample by a (Satellite FTIR 5000 of the wavelength range of 400 to 4000 cm-1) where the important bands and peaks of spinel structure can be assigned. A Fourier transform infrared spectroscopy collected by KBr pellet method, the material mixed with KBr of ratio 1:100 for FTIR measurement between 400 and 2000 cm-1 [
The UV-Visible absorption was investigated by UV Mini 1240 manufactured by Shimadzu company-Japan. Hydrochloric acid HCl was used as a reference for 100% absorbance [
Symmetry is important in the study of structural and optical properties of the nanoparticle ferrites.
D = 0.94 λ β cos θ (1)
where D is the average crystallite size, q is the angle, l is the incident of X-ray wavelength, while b is the (FWHM) of the highest intensity peak (311). The results of X-ray diffraction are listed in table 1.
No | Samples | Crystallite size (nm) | Lattice constant (Å) | Volume (nm3) | Space groups | Density (g/cm−3) |
---|---|---|---|---|---|---|
1 | Zn0.5mg0.5Fe2O4 | 15.97 | 8.382 | 588.90 | Fd-3m(227) | 0.656 |
2 | Zn0.5mg0.4Cu0.1Fe2O4 | 23.96 | 8.375 | 587.4 | Fd-3m(227) | 0.634 |
3 | Zn0.5mg0.3Cu0.2Fe2O4 | 20.94 | 8.380 | 588.5 | Fd-3m(227) | 0.650 |
4 | Zn0.5mg0.2Cu0.3Fe2O4 | 20.94 | 8.381 | 588.7 | Fd-3m(227) | 0.655 |
5 | Zn0.5mg0.1Cu0.4Fe2O4 | 28.33 | 8.397 | 591.1 | Fd-3m(227) | 0.657 |
Mg2+ (0.86 Å) compared with Cu2+ (0.73 Å) [
From table 1 we can observe that the density and volume increase with increasing Cu content. The increase in density and volume may be due to the ionic of constituent ions. After analysing the XRD data, the structural studies showed that all the samples prepared through the co-precipitation method are single phase of a face-centred Cubic (FCC) spinel and the symmetry structures with space group SG: Fd-3m.
Functional groups of the synthesize Zn0.5CuxMg0.5-xFe2O4are investigated by FTIR spectroscopy in the range of 400 to 4000 cm−1.
Eg (eV) | ν5 | ν4 | ν3 | ν2 | ν1 | Nano composites |
---|---|---|---|---|---|---|
4.67 | 2926 | 1637 | 1386 | 1112 | 576 | Zn0.5mg0.5Fe2O4 |
4.63 | 2923 | 1633 | 1387 | 1114 | 576 | Zn0.5mg0.4Cu0.1Fe2O4 |
4.07 | 2922 | 1632 | 1384 | 1112 | 576 | Zn0.5mg0.3Cu0.2Fe2O4 |
4.29 | 2921 | 1630 | 1382 | 1116 | 583 | Zn0.5mg0.2Cu0.3Fe2O4 |
4.04 | 2922 | 1633 | 1387 | 1117 | 576 | Zn0.5mg0.1Cu0.4 Fe2O4 |
Respectively for the all samples; the single-phases spinel structure having two lattices tetrahedral (A) site and octahedral (B) of site [
The diffused UV-visible absorption spectrum is recorded in order to obtain the optical band gap values of Zn0.5CuxMg0.5-xFe2O4 as shown in figure 5. The Maximum absorption displayed for sample 2 Zn0.5Cu0.2Mg0.3Fe2O4 was occurred at 245 Cm−1. However, with the doping of Cu2+ ion, the optical absorption properties of Nano-ferrites follow the band edge of equation (2) (table 2). In addition to that, the band gap energy was calculated for samples by Tauc plot [
[ F ( ( R ∞ ) h ν ) ] n = A ( h ν − E g ) (2)
where a, h,n, Eg and A are the absorption coefficient, plank constant, light frequency, band gap, and proportionality constant, respectively. The band gap values were found to be 4.67, 4.63, 4.07, 4.29 and 4.04 eV for X = 0.0, 0.1, 0.2, 0.3, and 0.4, respectively. This significant change in the band energies is due to the doping effects of Cu2+ ions crystal lattice [
Nano-ferrites samples which prepared by co-precipitation were investigated by XRD, FTIR and UV-vis. The lattice parameter was found to increase with copper concentration. Similarly, the size of crystals was found to increase from 15.97 nm to 28.33 nm. The FTIR bending vibration band of the samples confirmed the formation of spinal ferrite structure. The band gap energy calculated using Tauc plot and the absorption edge cut-off indicated that the samples possess insulator behavior.
Ali, B.M., Siddig, M.A., Alsabah, Y.A., Elbadawi, A.A. and Ahmed, A.I. (2018) Effect of Cu2+ Doping on Structural and Optical Properties of Synthetic Zn0.5CuxMg0.5-xFe2O4 (x = 0.0, 0.1, 0.2, 0.3, 0.4) Nano-Ferrites. Advances in Nanoparticles, 7, 1-10. https://doi.org/10.4236/anp.2018.71001