Controlling formation and assembling of nanoparticles by control of electrical charging, polarization, and electrochemical potential

Abstract

The well-known concept of electrical charging for the stabilization of colloidal solutions is extended to a general concept for explanation of behavior of nanoparticles during their formation, in their response behavior on chemical or electrochemical stress, and in particle/ particle interactions. This concept helps to understand the formation of polynuclear sphere-like plasmonic nanoparticles of gold, the surprising high stability of extended flat silver nanoprisms, and their switch-like transformation as well as the formation of special types of nanoparticle assemblies. It can be used for controlling the size of nanoparticles, for the synthesis of composite micro and nanoparticles, and for the generation of different classes of nonspherical polymer particles by particle/particle interactions during the process of particle growth. The reported experimental examples were mainly obtained by microfluidic experiments, which supplied a high homogeneity of the product particles. This high homogeneity is an excellent basis for studying the nanoparticle behavior in analogy to molecular processes and helps to get new insights in to the importance of electrical effects for nanoparticle synthesis and nanoparticle assembling.

Phase change materials for building construction: An overview of nano-/micro-encapsulation

“…Thereby, the polymerisation reaction gets initiated in the aqueous phase, which results in the growth of formed polymer particles due to progression of the polymerisation reaction [121]. This method is beneficial for the polymerisation of polymers and can be used to encapsulate designated PCM within a shell; thus, for the synthesis of nanocapsules (e.g.…”

Hierarchical Assemblies of Polymer Particles through Tailored Interfaces and Controllable Interfacial Interactions

“…[ 81 ] The formation of the systematically controlled linear and branched assembling polymer nanoparticles in a single‐step is based on the limited polarizability, partial electrostatic control, moderate repulsion, and hydrophobic interactions. [ 23,81,82 ] A systematic tuning in linear assembly and their surface charge has been systematically tuned in case of poly(methyl methacrylate) (PMMA) nanoparticles by using anionic polyelectrolytes polystyrene sodium sulfonate (PSSS) through semi‐microfluidic emulsion polymerization (Figure 2F). [ 23,81–83 ] While specific proteins—fusogens—plays the main role in cell membrane fusion, the role of polyelectrolytes in the case of assembling polymer nanoparticles is of central importance.…”

The Mixed-Electrode Concept for Understanding Growth and Aggregation Behavior of Metal Nanoparticles in Colloidal Solution

“…In general, electrical charges and self-polarization of charged non-spherical nanoparticles are key issues for the local deposition (or corrosion) rates of metal nanoparticles and can control the finally formed particle geometry. The concept of self-polarization can be used for the interpretation of experimental data on the growth of silver nanotriangles with sharp corners by growth of silver seeds in the presence of the polyanionic macromolecule Polystyrene sulfonic acid [22]. The negative functional groups of the polyanionic molecules push the negative charges into the corners of the triangles and cause an enhanced attraction of silver ions by the particle corners and the preferential deposition of silver in the corner region.…”

“…As well as composed spherical metal nanoparticles [19], metal rods, cubes, polyeders [20] as well as flat nanotriangles had been prepared to a high quality using microfluidic techniques [21]. The control of electrical surface charges also allowed the preparation of different types of polymer/polymer and polymer/metal composite particles [22]. Some examples are shown in Figure 1.…”