Abstract

An aqueous solution of tapioca starch was successfully used as a chelating agent in the solegel synthesis of Co0.7M-0.3Fe2O4, where Me denotes Co, Mn, Cu, Ni, or Zn. The hysteresis loops of all sintered ferrites revealed ferrimagnetic properties. The saturation magnetization was reduced in Co0.7Cu0.3Fe2O4 and Co0.7Ni0.3Fe2O4 because of the ion substitutions with smaller magnetic moments. Interestingly, Co0.7Cu0.3Fe2O4 exhibited the highest saturation magnetization and the lowest coercive field. This result demonstrates the value addition of local agricultural products in controlling nanoparticle formation during solegel synthesis.