title: Synthesis and spectroscopic characterization of copper zinc aluminum nanoferrite particles.
abstract: Copper doped zinc aluminum ferrites CuxZn1-x.(AlxFe2-x)O4 are synthesized by the solid-state reaction route and characterized by XRD, TEM, EPR and non linear optical spectroscopy techniques. The average particle size is found to be from 35 to 90nm and the unit cell parameter "a" is calculated as from 8.39 to 8.89Å. The cation distributions are estimated from X-ray diffraction intensities of various planes. The XRD studies have verified the quality of the synthesis of compounds and have shown the differences in the positions of the diffraction peaks due to the change in concentration of copper ions. TEM pictures clearly indicating that fundamental unit is composed of octahedral and tetrahedral blocks and joined strongly. The selected area electron diffraction (SAED) of the ferrite system shows best crystallinity is obtained when Cu content is very. Some of the d-plane spacings are exactly coinciding with XRD values. EPR spectra is compositional dependent at lower Al/Cu concentration EPR spectra is due to Fe(3+) and at a higher content of Al/Cu the EPR spectra is due to Cu(2+). Absence of EPR spectra at room temperature indicates that the sample is perfectly ferromagnetic. EPR results at low temperature indicate that the sample is paramagnetic, and that copper is placed in the tetragonal elongation (B) site with magnetically non-equivalent ions in the unit cell having strong exchange coupling between them. This property is useful in industrial applications. Nonlinear optical properties of the samples studied using 5ns laser pulses at 532nm employing the open aperture z-scan technique indicate that these ferrites are potential candidates for optical limiting applications.
authors.affiliation: Dept. of Physics, SVD College, Cuddapah 516 003, India. Electronic address: drslreddy_in@yahoo.com.
authors.forename: S
authors.initials: S
authors.lastname: Lakshmi Reddy
authors.affiliation: Dept. of Physics, SVD College, Cuddapah 516 003, India.
authors.forename: T
authors.initials: T
authors.lastname: Ravindra Reddy
authors.affiliation: Dept. of Physics, Raman Institute of Science, Bangalore, India.
authors.forename: Nivya
authors.initials: N
authors.lastname: Roy
authors.affiliation: Dept. of Physics, Raman Institute of Science, Bangalore, India.
authors.forename: Reji
authors.initials: R
authors.lastname: Philip
authors.affiliation: Dept. of Physics, Universidad Nacional de Colombia, Bogota, DC, Colombia.
authors.forename: Ovidio Almanza
authors.initials: OA
authors.lastname: Montero
authors.affiliation: Faculty of Engineering, Mie University, TSU, Mie 514 8507, Japan.
authors.forename: Tamio
authors.initials: T
authors.lastname: Endo
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia. Electronic address: r.frost@qut.edu.au.
authors.forename: Ray L
authors.initials: RL
authors.lastname: Frost
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D005290:Ferric Compounds; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D015032:Zinc / Q000737:chemistry*
chemical_list: D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; C001215:ferrite; D003300:Copper; D000535:Aluminum; D015032:Zinc
keywords: Copper doped zinc aluminum ferrite; EPR; Synthesis solid state reaction route; TEM; Tetragonal symmetry; XRD