Formation of Monodispersed Nano‐ and Micro‐Particles Controlled in Size, Shape, and Internal Structure

Abstract

Size control of monodispersed particles must normally be performed during the very short nucleation period, because the final particle number is determined by the end of the nucleation and it does not change until the end of the particle growth. On the other hand, the shape control is mainly performed by adsorption of shape controllers during the growth period, although in some cases the crystal structure of the nuclei may have essential influence on the morphology of the grown particles. The internal structure of each particle is often strongly affected by the action of shape controllers. This article deals with the fundamental mechanisms of the nucleation, growth, and structural formation of monodispersed nano-and micro-particles, leading to the control of their size, shape, and internal structure.

A closer look at the synthesis and formation mechanism of hematite nanocubes

“…Nanosized hematite has been synthesized in various shapes such as cubes [7][8][9], rods [10], spheres [11,12], pseudocubes [12], platelets [13], ellipsoids [14,15], nanobelts and dendrite micro pines [16,17]. The final hematite particle size and shape can be tuned by adjusting synthesis parameters such as the concentration of the reactants [7], duration of the reaction [18], ionic strength [19,20], reaction temperature, surfactants [10], presence of hematite seed [21] and pH of the solution [19]. The addition of organic additives to aqueous reaction mixtures was shown to have an appreciable effect on the geometry of hematite particles [22].…”

Size-Controlled Hydrothermal Synthesis of Bismuth Sodium and Bismuth Potassium Titanates Fine Particles and Application to Lead-Free Piezoelectric Ceramics

“…17,18) This synthetic systems will be expected to control precisely nano-structures of BNT-and BKT-based novel-types of piezoelectric ceramics. Recently, we have developed preparation technique of BNT fine particles from aqueous solutions by applying the Gel-Sol method, 19) which is one of a liquid phase particle synthesis system for the precise control of size, shape, composition, and structure of monodispersed particles in large quantities, developed by Sugimoto et al 20) The synthesis method has a better record on the preparation of monodispersed hematite, [21][22][23][24] TiO 2 , [25][26][27][28][29][30][31] and BaTiO 3 particles with perovskite-structure. 32) We have been applying this method to the preparation of various shapes of BNT fine particles controlled in their size and shape, such as sphere, rod, and nanotube.…”

Tailoring Porosity of Colloidal Boehmite Sol by Controlling Crystallite Size

“…This process is very similar to the gel-sol method developed by Sugimoto, since the boehmite nanoparticles were synthesized in the form of a stable sol from a gel. 24 In the gel-sol process, the nucleation rate is generally determined by the initial concentration of some specific precursor complexes as solute species. Consequently, this factor has influence on the particle growth for controlling final particle size.…”