Synthesis of alkyl sulfonate/alcohol-protected γ-Fe2O3 nanocrystals with narrow size distributions

Synthesis of iron oxide nanoparticles in a polyimide matrix

“…Among those materials, γ -Fe 2 O 3 has been extensively studied due to its excellent magnetic properties [4,5]. Although γ -Fe 2 O 3 nanoparticles have been produced through different synthesis routes [6][7][8][9][10][11][12], it was observed that the nanoparticles manifested very different physical properties depending on their microstructure, such as size uniformity and crystallinity. Therefore, developing a synthesis method that can maintain size uniformity and crystallinity is critical for the application of these nanoparticles [9].…”

Complexation of the Fe(III) and Fe(II) sulphates with diphenyl-4-amine barium sulphonate (DAS) Synthesis, thermogravimetric and spectroscopic studies

“…For Fe 3 O 4 , the methods described are various, such as precipitation in the presence of polyvinyl alcohol, chemical reduction of a-Fe 2 O 3 , decomposition of oxalates, citrates and hydroxides [3][4][5][6]. Production of a-Fe 2 O 3 nanoparticles involves from application of thermal transformations of metallic iron under oxidizing atmospheres, thermal oxidation of Fe 3 O 4 , iron salts hydrolysis until the use of surfactants containing large carboxylate alkyl chains [1,2,5,7,8]. Surfactants act in order to prevent the aggregation of a-Fe 2 O 3 nanoparticles into clusters generated by the anisotropy of the dipolar attraction, which, by changing, causes loss of properties associated to the single domain.…”

“…Surfactants act in order to prevent the aggregation of a-Fe 2 O 3 nanoparticles into clusters generated by the anisotropy of the dipolar attraction, which, by changing, causes loss of properties associated to the single domain. In the last years, successful protection of a-Fe 2 O 3 nanoparticles have sometimes been achieved by using anionic alkyl-sulphonate surfactants such as dodecylbenzene sulphonate and 1-undecane sulphonic acid, besides 1-octanol (alcohol) [7]. It has been emphasized that surfactants may stabilize the morphology of Fe 3 O 4 , even though it depends on the initial amount of Fe(II) present in the process.…”

“…However, particle sizes are between 2 and 20 nm in order to control these factors. Despite the advances, the points of view are not unanimous about the exact role of surfactants [1,7]. Some inconveniences from the use of surfactants have been pointed out due to the difference on the interaction between the latter and the surface and inside of the particles [1].…”

Nanoparticles fabricated by selective reaction of Fe100−xPtx alloy films during imidization of polyamic acid

“…Although many different methods of synthesizing nanoparticles have been developed over the years, in order to consistently reproduce and utilize the size-dependent properties of these nanoparticles, particle size, size distribution, structure, and composition must be precisely controlled [1,2]. Many researchers have been successful in fabricating monodisperse metal and oxide particles in the size range of 1-20 nm, arranged in a regular superlattice [3][4][5]; however, the selfassembling process, largely relying on the weak van der Waals force of organic surfactants, is difficult to control.…”