Effect of aluminum substitution on the structural and magnetic properties of cobalt ferrite synthesized by sol–gel auto combustion process

摘要: Abstract Aluminum substituted cobalt ferrite powders (CoFe2−xAlxO4) with varying composition from 0.0 to 1.0 in the step of 0.2 have been obtained by sol–gel auto combustion technique using citric acid as a fuel. The metal nitrate fuel ratio was maintained 1:4 throughout synthesis CoFe2−xAlxO4. thermal analysis prepared samples is done TGA technique. compositional stoichiometry confirmed Energy dispersive X-ray Single phase cubic spinel structure and nano synthesized were diffraction (XRD) scanning electron microscopy (SEM). crystallite size 16–26 nm Scherrer formula. SEM shows formation uniform grain growth. results order 30 nm. Maximum specific surface area observed be 52 m2/gm. highest value saturation magnetization coercivity for pure sample it decreases aluminum content x increases. A strong co-relation between observed. decrease magnetic properties due substitution ions place Fe3+.