Synthesis and properties of barium ferrite nano-powders by chemical co-precipitation method

•Ba-ferrite nanoparticles with good properties are synthesized by optimized process.•These nanoparticles show high coercivity and good thermal stability.•Excessive Ba ions is necessary for the synthesis of single phase particles.•The particle sizes are well controlled in the single domain size range. Nano-powders with controllable particle size, excellent magnetic properties and thermal stability of barium hexaferrite (BaFe12O19) have been synthesized via a co-precipitation/calcination technique. The phase composition, morphology and magnetic/thermal properties of the products were systematically studied. XRD patterns reveal that a long co-precipitation reaction time (5 h) and high calcination temperature (1100 °C) are beneficial for the formation of BaFe12O19 phase and decreasing the tendency to agglomeration. SEM micrographs show that the products show a hexagonal flake-like particle shape and the size are well controlled and maintained at single-domain particle size range area (