Lee, SW Ryu, YG Yang, KJ Jung, KD An, SY Kim, CS 2024-01-21T10:38:34Z 2024-01-21T10:38:34Z 2021-09-01 2002-05-15 0021-8979 https://pubs.kist.re.kr/handle/201004/139535 Ultrafine Co1-xZnxFe2O4 (0less than or equal toxless than or equal to1.0) particles are fabricated by a sol-gel method. The magnetic and structural properties of powders were investigated with x-ray diffraction, vibrating samples magnetometer and Mossbauer spectroscopy. The lattice parameter (a(0)) increases linearly with increasing Zn concentration (x) and follows Vegard's law approximately. Co0.9Zn0.1Fe2O4 powders that were annealed at and above 673 K have only a single phase spinel structure and behave ferrimagnetically. Powders annealed at 523 K and 573 K have a typical spinel structure and are simultaneously paramagnetic and ferrimagnetic in nature. The magnetic behavior of Co0.9Zn0.1Fe2O4 powders annealed at and above 573 K shows that an increase of the annealing temperature yields a decrease of the coercivity and an increase of the saturation magnetization. The maximum coercivity and the saturation magnetization of Co0.9Zn0.1Fe2O4 ferrite powders are 1328 Oe and 81.1 emu/g, respectively. Mossbauer spectra of Co-Zn ferrite have been taken at various temperatures from 20 to 800 K. The isomer shifts indicate that the iron ions were ferric at the tetrahedral [A] and the octahedral [B]. The Neel temperature of Co0.9Zn0.1Fe2O4 was determined to be T-N=790 K and It is found that Debye temperature for the A and B sites of the sample annealed at 1123 K is found to be Theta(A)=756+/-5 K and Theta(B)=199+/-5 K, respectively. The Neel temperature dramatically decreased with increasing x from about T-N=870 K for x=0.0 to T-N=35 K for x=1.0. (C) 2002 American Institute of Physics. English AMER INST PHYSICS MOSSBAUER Magnetic properties of Zn2+ substituted ultrafine Co-ferrite grown by a sol-gel method Article 10.1063/1.1452215 1 JOURNAL OF APPLIED PHYSICS, v.91, no.10, pp.7610 - 7612 JOURNAL OF APPLIED PHYSICS 91 10 7610 7612 scie scopus 000175575100262 2-s2.0-0037095291 Physics, Applied Physics Article; Proceedings Paper MOSSBAUER sol-gel method