Synthesis of iron oxide nanoparticles via biopolymer method

Abstract

Due to its properties like low cost and uncomplicated methods to produce, iron (III) alginate is used to produce crystalline Fe2O3 nanoparticles. Iron (III) alginate gels were prepared and then thermal decomposition technique is used to convert the gels into iron oxide nanoparticles. After the synthesis, the effect of the annealing on the crystallite size was investigated. X-ray diffractometry is used to characterize the produced powder. The size of iron oxide nanoparticles changed relying on temperature and time, between 22 to 32 nm. The grain size distribution was calculated using a numerical method, considering the full width at 1/5 and 4/5 of maximum (FW1/5M) and (FW4/5M) of the XRD peaks. In order to observe the effect of annealing, samples were annealed at two different temperatures, 600 and 800oC and at two different times 2 and 4 h. The results showed that the grain size distribution (GSD) became non-symmetrical when the post-annealing applied with increasing temperature and time, and this method considered has low effect on the width of distribution for powder produced under heat treatment.