eprintid: 2229 rev_number: 2 eprint_status: archive userid: 1 dir: disk0/00/00/22/29 datestamp: 2023-11-09 15:50:26 lastmod: 2023-11-09 15:50:26 status_changed: 2023-11-09 15:42:17 type: article metadata_visibility: show creators_name: Yahya, N. creators_name: Al Habashi, R.M. creators_name: Koziol, K. creators_name: Borkowski, R.D. creators_name: Akhtar, M.N. creators_name: Kashif, M. creators_name: Hashim, M. title: Morphology and magnetic characterisation of aluminium substituted yttrium-iron garnet nanoparticles prepared using sol gel technique ispublished: pub keywords: 1.8 GHz; Aluminum atoms; Compositional variation; D-spacing; High purity; High-resolution transmission electron microscopes; Initial permeability; Moderate value; Nanocrystalline particle; Resonance frequencies; Sintering temperatures; Sol-gel technique; Structural change; Sub-lattices; Super-exchange interactions; Superexchange interaction; Tetrahedron; Yttrium iron garnets, Aluminum; Computational mechanics; Electron diffraction; Exchange interactions; Garnets; Gels; Geometry; Morphology; Nanomagnetics; Nanoparticles; Single crystals; Sintering; Sols; Transmission electron microscopy; X ray diffraction; Yttrium, Yttrium alloys, aluminum; iron; nanomaterial; yttrium, article; chemistry; crystallization; magnetism; materials testing; methodology; particle size; phase transition; ultrastructure, Aluminum; Crystallization; Iron; Magnetics; Materials Testing; Nanostructures; Particle Size; Phase Transition; Yttrium note: cited By 11 abstract: Aluminum substituted yttrium iron ga rnet nano particles with compositional variation of Y 3.0-x Al xFe 5O 12, where x = 0.0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 were prepared using sol gel technique. The X-ray diffraction results showed that the best garnet phase appeared when the sintering temperature was 800 °C. Nano-crystalline particles with high purity and sizes ranging from 20 to 100 nm were obtained. It was found that the aluminum substitution had resulted in a sharp fall of the d-spacing when x = 2, which we speculated is due to the preference of the aluminum atoms to the smaller tetrahedron and octahedron sites instead of the much larger dodecahedron site. High resolution transmission electron microscope (HRTEM) and electron diffraction (ED) patterns showed single crystal nanoparticles were obtained from this method. The magnetic measurement gave moderate values of initial permeability; the highest value of 5.3 was shown by sample Y 3Fe 5O 12 at more than 100 MHz which was attributed to the morphology of the microstructure which appeared to be homogeneous. This had resulted in an easy movement of domain walls. The substitution of aluminum for yttrium is speculated to cause a cubic to rhombodedral structural change and had weakened the super-exchange interactions thus a fall of real permeability was observed. This might have created a strain in the sub-lattices and had subsequently caused a shift of resonance frequencies to more than 1.8 GHz when x > 0.5. © 2011 American Scientific Publishers. date: 2011 official_url: https://www.scopus.com/inward/record.uri?eid=2-s2.0-79955826465&doi=10.1166%2fjnn.2011.2723&partnerID=40&md5=7be53c7a09702b405cf0b4ce408fac13 id_number: 10.1166/jnn.2011.2723 full_text_status: none publication: Journal of Nanoscience and Nanotechnology volume: 11 number: 3 pagerange: 2652-2656 refereed: TRUE issn: 15334880 citation: Yahya, N. and Al Habashi, R.M. and Koziol, K. and Borkowski, R.D. and Akhtar, M.N. and Kashif, M. and Hashim, M. (2011) Morphology and magnetic characterisation of aluminium substituted yttrium-iron garnet nanoparticles prepared using sol gel technique. Journal of Nanoscience and Nanotechnology, 11 (3). pp. 2652-2656. ISSN 15334880