Microstructural study and size control of iron oxide nanoparticles produced by microemulsion technique

Abstract

In this paper we study the possibility to control the size of iron oxide (Fe 3 O 4 ) nanoparticles by the microemulsion technique. We used a water-in-oil reverse microemulsion system with n-hexadecil trimethylammonium bromide (CTAB) as a cationic surfactant, n-butanol as a co-surfactant, n-hexanol as a continuous oil phase, and aqueous phase. The magnetite nanopowders were synthesized by a single microemulsion technique in which the aqueous phase contains only metal ions (Fe 2+ and Fe 3+). The particle size of the powders varied in the range of 14-36 nm depending on the preparation conditions. We studied the influence of changing the water/surfactant ratio (W 0 = 5, 10, 15, 20) and the metallic ion (Fe 2+ and Fe 3+ ) concentration on the particle size distribution and crystallinity of Fe 3 O 4 .

Simulation of the kinetics of nanoparticle formation in microemulsions

“…However, several different types of behaviour have been observed when the droplet size increases: increasing of particle size [25][26][27], bimodal distributions [28,29], and essentially no control by droplet size [29][30][31][32]. Although water droplets are not real templates, the combination of the droplet size with the parameters discussed above can be used to obtain very precise control of the final particle size.…”

Characterization of iron hydroxide/oxide nanoparticles prepared in microemulsions stabilized with cationic/non-ionic surfactant mixtures

“…The weak and broad peak at 400°C indicate the small (nanosize) crystallite size but upon calcination, a crystallite growth is evident from the increase in the sharpness of the peaks. It is worth mentioning here that, as per the literature, some microemulsion mediated iron oxide syntheses yield magnetite, Fe 3 O 4 , when mixed-valency iron ions were used [41]. Uncalcined powder prepared using the NH 3 route is amorphous and the three peaks for uncalcined powder shown in Fig.…”

Surfactant effects on the particle size of iron (III) oxides formed by sol–gel synthesis

“…Nanomaterials represent a new class of materials that possess distinctive physical and chemical properties that differ substantially from their micron-size and bulk counterparts [3][4][5]7,8,10,[12][13][14][15][16][17][18][19]. In order to harvest and translate the fascinating properties of materials at the nanoscale size domain into viable, affordable new technologies, it is imperative that new, facile synthesis and manufacturing methods could be developed in order to create the fundamental building blocks of the nanomaterials and their subsequent assembly into useful devices.…”

“…Of the multitude materials of interest, iron oxide nanoparticles offer a potential compatibility as material building blocks for a particularly broad range of applications, such as magnetic materials, catalysts, sensors (chemical, electronic and biological), data storage materials, MRI contrast agents and drug delivery facilitators [7,8,10,[12][13][14][15]17,19,21]. Hence, the design, synthesis and large scale manufacturing of various types iron oxides with tight control on particle size, size distribution and particle geometry and morphology, has become one the most important research avenues in the area of nanomaterials synthesis.…”

“…The design, development, manufacturing and utilization of nanomaterials have become very broad and vigorously growing fields of research in recent years [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. Nanomaterials represent a new class of materials that possess distinctive physical and chemical properties that differ substantially from their micron-size and bulk counterparts [3][4][5]7,8,10,[12][13][14][15][16][17][18][19].…”