Sodium-hydroxide molarities influence the structural and magnetic properties of strontium-substituted cobalt ferrite nanoparticles produced via co-precipitation

Abstract

The Sr-substituted CoFe2O4 nanoparticles have been synthesized using the co-precipitation technique with three different molarities of the sodium-hydroxide. The XRD analysis reveals the increase in molarities (1.5 ​M, 3 ​M, 4.8 ​M) causing a decrease in crystallite size (33.9, 30.6, and 28.6 ​nm) and an increase in lattice strain (3.36 x 10−3, 3.71 x 10−3, and 3.98 x 10−3). The results of grain size measurements with Scanning Electron Microscopy were inversely proportional with crystallite sizes, namely 36 ​nm, 43 ​nm, and 47 ​nm. Meanwhile, the larger particle size is obtained for the higher molarities, which conforms with the lower Raman intensity for the higher molarities. Furthermore, the base solution molarity significantly controls the magnetic properties of Sr-substituted CoFe2O4. The increase in molarities leads to a decrease in coercivity, magnetization saturation, and magnetic remanent.