Synthesis and Characterization of Nanocrystalline Ca₂Cu₂Fe_(12-x)Al_xO₂₂ Y-Type Hexaferrites by the Sol–Gel Combustion Method

Abstract

Nano-size Y-type hexaferrites powders are synthesized by using the sol–gel combustion method in nitrate urea systems. The X-ray diffraction patterns of Ca₂Cu₂Fe_(12-x)Al_xO₂₂ annealed above 800 °C manifest that all the species have hexagonal crystal structure. TEM observation of as-burnt powders of Ca₂Cu₂Fe_(12-x)Al_xO₂₂ shows the powder particles have an average particle size of 23 nm. Magnetic hysteresis loop measurements of the series Ca₂Cu₂Fe_(12-x)Al_xO₂₂ exhibit that the saturation magnetization (M_s), the remanent magnetization (M_r) and the coercitivity (H_c) of compounds depend strongly on the chemical composition of materials. The maximum values of M_s (1.2898E-3 emu/g) and M_r (87.099E-3 emu/g) and the areas of magnetic hysteresis loop of compounds decrease with increasing the value of Al.

Keywords:

• Hexaferrites
• Ca-M ferrites substitutions
• magnetic properties
• VSM
• TEM
• PXRD
• dielectric loss

Acknowlegment

The authors acknowledge IIT Powai, IIT Madras, SAIF Kochi, and Delhi University for providing instrumental facility.