Rapid Synthesis of Monodispersed .ALPHA.-Fe2O3 Nanoparticles from Fe(NO3)3 Solution by Microwave Irradiation

Abstract

Monodispersed aFe 2 O 3 nanoparticles were prepared at 100 , 120 , and 140 C using 0.02, 0.05, and 0.1 MFe(NO 3 ) 3 E9H 2 O solutions by microwavehydrothermal (MH) and conventionalhydrothermal(CH) reac tions. Compared to the formation of monodispersed aFe 2 O 3 particles using the CH reaction, the MH reaction led to increased rate of formation by 3 times at 120 C and 5 times at 140 C from 0.1 MFe(NO 3 ) 3 solutions. aFe 2 O 3 nanoparticles of 2325 nm in diameter were obtained from 0.02 M solution at 100 C after treatment for 4 h by applying microwaves, which led to the formation of smaller sized particles with a narrow particle size distribution. The coagulation of nanosized single crystals of 5 to 6 nm in diameter was enhanced by increasing the concentration of Fe(NO 3 ) 3 solutions.