Effect of reaction condition on microstructure and properties of (NiCuZn)Fe2O4 nanoparticles synthesized via co-precipitation with ultrasonic irradiation

Nano-spinel ferrites synthesized via chemical co-precipitation method are small in size and have serious agglomeration phenomenon, which makes separation difficult in the subsequent process. Ni_0.4Cu_0.2Zn_0.4Fe₂O₄ ferrites nanoparticles were synthesized via co-precipitation assisted with ultrasonic irradiation produced by ultrasonic cleaner with 20 kHz frequency using chlorinated salts and KOH as initial materials. The effects of ultrasonic power (0, 40 W, 60 W, 80 W) and reaction temperature on the microstructure and magnetic properties of ferrite nanoparticles were investigated. The structure analyses via XRD revealed the successful formation of pure (NiCuZn)Fe₂O₄ ferrites nanospinel without any impurity. The crystallites sizes were less than 40 nm and the lattice constant was near 8.39 Å. The TEM showed ferrite particle polygonal. M−H analyses performed the saturation magnetization and coercivity of ferrite nanoparticles obtained at the reaction temperature of 25℃ were higher than at 50℃ with same power. The samples exhibited the highest values of Ms 55.67 emu/g at 25℃ and 47.77 emu/g at 50℃ for 60 W and the lowest values of Hc 71.23 Oe at 25℃ for 40 W and 52.85 Oe at 50℃ for 60 W. The squareness ratio (SQR) were found to be lower than 0.5, which revealed the single magnetic domain nature (NiCuZn)Fe₂O₄ nanoparticles. All the outcomes show the ultrasonic irradiation has positive effects on improving the microstructure and increasing magnetic properties.