Dispersion control of Fe2O3 nanoparticles using a mixed type of mechanical and ultrasonic milling

Abstract

alpha-Fe2O3 nanoparticles with controlled dispersion were obtained by using a mixed type of mechanical and ultrasonic milling with the addition of surfactant, in which particle refinement was done mechanically, and dispersion was done physically and chemically. The particle refinement and dispersion degree of the alpha-Fe2O3 were examined by TEM observation and analyses of turbidity as well as FT-IR spectra of the particle-dispersed solution. Smaller particle size and addition of 1% n-octyl alcohol surfactant make the dispersion effect better. This improved dispersion of the nanoparticles was attributable to increased adsorption of hydroxide ions on alpha-Fe2O3 nanoparticle surfaces as its area increased. (C) 2002 Elsevier Science B.V. All rights reserved.