Kamla Nehru Mahavidyalaya or the Kamla Nehru College (known as the K.N. College) is a degree college located in Korba, Chhattisgarh, India. It was established by the Kamla Nehru Mahavidyalaya Samiti in 1971.
This communication covers the synthesis of magnesium-copper-zinc nanocrystalline spinel ferrites, with the general formula Mg0.55Cu0.15Zn0.30Fe2-xRx=0,0.2O4 (R=Sm3+, Nd3+, Al3+, Cr3+), using a microwave-assisted sol-gel auto-combustion method with a variety of rare earth (Sm3+, Nd3+) and trivalent (Al3+, Cr3+) elements. This paper is about connecting the different properties of nanocrystalline spinel ferrites that were made. These properties include their microstructure, spectroscopic, optical, magnetic, and dielectric. They were studied using powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The techniques used for analysis include Fourier-transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-Vis), vibrating sample magnetometry (VSM), and impedance analysis. The PXRD data verified the establishment of a single-phase cubic spinel structure. The crystallite size got smaller when Sm3+, Nd3+, Al3+, and Cr3+ ions were added to Mg-Cu-Zn spinel ferrites. The SEM micrographs revealed a nearly spherical, agglomerated, and granular structure of nanoferrites. Furthermore, the emergence of two significant absorption bands validated the spinel ferrite structure. According to the Tauc plot method, the UV-Vis analysis shows that the optical band-gap energy of the synthesized spinel ferrite is between 1.50 and 1.62 eV. This means that they can be used in optoelectronics. Magnetic characteristics were assessed utilizing a VSM with an applied magnetic field of up to +/- 15 kOe at 300 K. All generated samples demonstrate a progressive decline in dielectric constant, dielectric loss, and loss tangent with increasing frequency; a hallmark property of spinel ferrites.
Spinel ferrite nanoparticles (SFNPs), such as Mg0.2Ni0.6Zn0.2Fe2O4, have unique properties that are influenced by their synthesis methods. Different bottom-up approaches, including sol-gel, auto-combustion, hydrothermal, and co-precipitation method were used to prepare these nanoparticles. Structural, morphological, optical and magnetic properties were analysed using techniques like X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscope (TEM), scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). Crystallite sizes measured using Scherrer's formula were 28.9 nm, 20.2 nm, and 7.5 nm for the respective synthesis methods. FTIR spectra indicated metal-oxygen bond formation, TEM and SEM confirms cubical shaped morphology while VSM analysis revealed the pseudo-single domain nature of the synthesized SFNPs. The observed and estimated parameter strongly suggests that these materials could be used in biomedical and electronic applications.
A series of Sm3+ activated BaAl₂O₄ phosphors was effectively synthesized by a known combustion method. Structural and optical properties are investigated by using X-ray diffraction pattern (XRD), Fourier transform infrared (FTIR), and photoluminescence (PL) analysis. The XRD of the prepared sample exhibits that all the samples prepared are in a single phase and match with standard JCPDS no. 01–072-1331. The XRD pattern indicates a hexagonal structure. The FTIR spectra of the BaAl₂O₄ sample show the stretching vibrations of aluminum-oxygen, barium-oxygen, and barium-oxygen-aluminum bonds, confirming the presence of the BaAl₂O₄ structure. The luminescence properties are broadly investigated by recording their PL excitation and emission spectra. The BaAl₂O₄:Sm3+ phosphors show a strong absorption range in 340–420 nm, which is well suited for application in LEDs. Under the excitation wavelength of 403 nm, the BaAl₂O₄:Sm3+ phosphor emits yellow, orange, and red emissions along the Commission Internationale de l'Éclairage (CIE) chromaticity coordinates found at 565 nm (0.408, 0.589), 603 nm (0.640, 0.359), and 650 nm (0.725, 0.274) (0.615). The optimal doping concentration of Sm3+ doped BaAl₂O₄ is at 1 mol
Two series of Mn0.5Zn0.5Fe2–xO4Rx (where R = Ce, Y, and x = 0.00 to 0.15) spinel nanoferrites were synthesized via a co-precipitation approach. Methods including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), and scanning electron microscopy (SEM) were utilized to examine the samples’ structural, morphological, optical, and magnetic features. XRD confirmed a cubic spinel structure, with crystalline sizes lies between 16 and 24 nm for Ce3+ added and 15 and 19 nm for Y3+ added ferrite NPs. XRD analysis showed that Ce3+ and Y3+ ions were successfully incorporated into the Mn–Zn spinel structure. FTIR spectra validated the presence of tetrahedral (A) and octahedral (B) sites in all compositions of Mn0.5Zn0.5Fe2–xO4Rx nanoparticles, indicative of spinel ferrites exhibiting a face-centered cubic (FCC) structure. SEM studies revealed agglomerated nanoparticles with spherical morphology. Energy dispersive X-ray spectroscopy (EDS) verified that all elements are present in the composition. The TEM micrograph shows the existence of slightly agglomerated nanoparticles. Magnetic properties, including saturation magnetization and coercivity, were analyzed using M–H hysteresis curves, showing dependence on rare earth substitution and A–B exchange interactions. The lower value of coercivity (Hc) indicatied of soft nature of NPs. The multidomain nature of the nanoferrites indicates their potential for electronics applications.
