Effect of organic solvents on iron oxide nanoparticles by the solvothermal method

gamma-Iron oxide nanoparticles were produced by the solvothermal method at 250-300 degrees C. Phase identification, crystal size analysis, and morphology were performed using X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The influences of iron(III) acetylacetonate concentration and reaction time on nanoparticles suggested differences in the crystallization pathway of products prepared in 1,4-butanediol and in toluene. Iron oxides prepared in 1,4-butanediol have been proposed to crystallize and precipitate from glycoxide, while those prepared in toluene are obtained by thermal decomposition of iron(III) acetylacetonate. The calcinations of nanoparticles at 350 degrees C indicated that iron oxides prepared in 1,4-butanediol have a higher thermal stability than those prepared in toluene due to phase transformation from gamma- to alpha-iron oxides in samples prepared in toluene.