American Journal of Materials Science and Application 2019; 7(1): 13-18 http://www.openscienceonline.com/journal/ajmsa ISSN: 2381-6074 (Print); ISSN: 2381-6090 (Online) Curie Points and Direct Current Electrical Conductivity for Inverse Li-Spinel Ferrite Replaced by Zn 2+ Ion Hussein Dawoud * , Zana Abu Mosa, Samy Shaat Department of Physics, Faculty of Science, Islamic University, Gaza, Palestine Email address * Corresponding author To cite this article Hussein Dawoud, Zana Abu Mosa, Samy Shaat. Curie Points and Direct Current Electrical Conductivity for Inverse Li-Spinel Ferrite Replaced by Zn 2+ Ion. American Journal of Materials Science and Application. Vol. 7, No. 1, 2019, pp. 13-18. Received: August 1, 2018; Accepted: August 27, 2018; Published: April 29, 2019 Abstract The conventional ceramic double sintering method was used to prepare a series of mixed Li-Zn spinel ferrites (SFs) Direct electric (DC) electrical conductivity (σ) and inductance (L) were studied for the prepared series of samples from room temperature to well beyond the Curie point (T C ). σ was measured as a function of temperature, the relation between lnσ with 1/T indicated that σ was increased with increasing of the temperature, which proves that the prepared samples have a semiconductor behavior. The maximum value of the σ was reported for the sample of x = 0.8. The σ results were interpreted in terms of hopping model. The relation between lnσT and 1/T showed a change in the slope which is attributed to the change of samples from ferrimagnetic to paramagnetic at T C . The values of L increased exponentially from room temperature up to T C , and then they decreased sharply. The calculated activation energy E a in the ferromagnetic region was less than that in paramagnetic region. The calculated activation energy (E a ) decreased with increasing of Zn content. The values of the T C for the prepared samples were determined from σ and L measurements, which decreased with increasing of Zn content. Keywords Spinel Ferrite, DC Electric Conductivity, Curie Point, Inductance, Activation Energy, Defect, Vacancies 1. Introduction Spinel ferrites have received immense attention due to their novel magnetic, optical, electric, dielectric and catalytic properties [1-5], chemical and thermal stability, mechanical hardness, memory storage capacity, easy to synthesize and reasonable cost [5-9]. Spinel ferrites have wide extended applications encompass an impressive in different fields due to their interesting electrical properties [10, 11]. The electrical properties of spinel ferrites are sensitive to their composition and microstructure, which in turn are sensitive to their processing conditions. Lithium and substituted lithium ferrite are gaining importance because of their technological applications ranging from microwave to radio frequency. It was reported that Li–Zn ferrites showed a reversible loss of oxygen, on the other hand irreversible volatilizations of the Zn and the Li above approximately 1000°C [12]. The loss of Zn and Li imply to appearance of α- Fe 2 O 3 , which is linked to the excess Fe content. As a result, this leads to a cation-non-deficient spinel phase, therefore, the reduction of Fe 3+ to Fe 2+ increases. Therefore, for the most part, the conductivity increases with sintering temperature. Furthermore, the high-temperature spinel phase is maintained by quenching (fast cooling) [12]. Where during slow cooling, oxygen atoms can return to the cubic lattice and re-oxidize most of the Fe 2+ and Fe 3+ but not all. In addition, the conductivity of the precipitated α-Fe 2 O 3 has extremely high conductivity. The results give an account of electrical conductivity which is decreased not only an account of electrical conductivity which is decreased not only by the oxygen reintegration and the re-oxidation of Fe 2+ ions during slow cooling, but also by the nature of precipitation of above approximately 1000°C [12]. In this study, the composition and cation distribution of the mixed Li-Zn spinel ferrites exhibits various electric properties. Therefore, a