Microwave losses of nanostructure Li-Ni ferritesin X-band and Ku-band

Abstract

The molar ratio)x( of Li-Ni ferrites in the formula Li0.5-0.5xNixFe2.5-0.5xO4 was varied in range 0.1-1.0 by hydrothermal process. The XRD, SEM, and TEM tests were conducted to examine the samples crystalline phase and to characterize the particles shapes and sizes. Thehigh purity spinel structure was obtained atmed and high x values.SEM and TEMimages showed the existence of different ferrite particles shapes like nanospheres and nanorods.The maximum particle size is around (20nm). These size encourage occurrence of super paramagnetic state. The reflection loss and insertion loss as microwave losses of Li-Ni ferrite-epoxy composite of 1mm thickness and mixing ratio 39.4 wt was investigated. The minimum reflection loss in x-band and in Ku band was about -8dB around 10GHz and lower than -18dB respectively. The insertion loss exceeded -6dB in the two band for some samples.