Influence of preparation method on structural and magnetic properties of nickel ferrite nanoparticles

• DOI: 10.1007/s12034-011-0326-7
• Publication Date: 2012-06-18T12:07:48Z
• Authors: Binu P. Jacob; Ashok Kumar; R. P. Pant; Sukhvir Singh; E. M. Mohammed
• Keywords: Ferrimagnetism; Superparamagnetism

Nickel ferrite nanoparticles of very small size were prepared by sol-gel combustion and co-precipitation techniques. At the same annealing temperature sol-gel derived particles had bigger crystallite size. In both methods, crystallite size of the particles increased with annealing temperature. Sol-gel derived nickel ferrite particles were found to be of almost spherical shape and moderate particle size with a narrow size distribution; while co-precipitation derived particles had irregular shape and very small particle size with a wide size distribution. Nickel ferrite particles produced by sol-gel method exhibited more purity. Sol-gel synthesized nanoparticles were found to be of high saturation magnetization and hysteresis. Co-precipitation derived nickel ferrite particles, annealed at 400°C exhibited superparamagnetic nature with small saturation magnetization. Saturation magnetization increased with annealing temperature in both the methods. At the annealing temperature of 600°C, co-precipitation derived particles also became ferrimagnetic.