Nanoscale monodispersity

Polymer-protected, monodisperse, nanoscale silver particles (Fig. 9.2.1c and d) have been obtained through spontaneous nucleation by the polyol process as follows (23). PVP (1-25 g) and AgNOj (50-3200 mg) were dissolved in EG (75 mL) at room temperature. Then the solution was heated up to 120°C at a constant... 

Ag-Pd Alloy Powders (7,27). Bimetallic colloids, namely, Ag-Pd and Au-Pt, can be obtained by the polyol process. The composition Ag7oPdx> is of particular interest to make the internal electrodes of multilayer ceramic capacitors (MLCC). Polymer-protected, monodisperse, nanoscale Ag70Pd30 particles have been obtained... 

Metal clusters have been considered as models for monodispersed nanoscale metal particles in a dielectric matrix or as precursors for nanoscale particles (see Chapter 12.03 for organometallic-derived metals, colloids, and nanoparticles). The number of metal atoms in well-defined molecular compounds can be varied from 2 to 3 up to hundreds, and the physical properties change from localized molecular to nearly bulk metal. They offer the advantage that clusters can be studied by a wide variety of experimental techniques. 

Korpe DA, Malekghasemi S, Aydin U, Duman M. Fabrication of monodispersive nanoscale alginate-chitosan core-shell particulate systems for controlled release studies. J Nanopart Res 2014 16(12) 9. 

In the above two independent studies, the feasibility of CPMV as a nanobuilding block for chemical conjugation with redox-active compounds was demonstrated. The resulting robust, and monodisperse particles could serve as a multielectron reservoir that might lead to the development of nanoscale electron transfer mediators in redox catalysis, molecular recognition, and amperometric biosensors and to nanoelectronic devices such as molecular batteries or capacitors. 

The volume is closed with a contribution by J. Bibette who describes and illustrates a simplified process of making monodisperse emulsions and emulsion based particles with predictable size and size distribution by a simple shearing device. I regard this very flexible route as important for the conception of many future particle-based systems, devices and procedures, and it is rather the rule than the exception that colloid chemistry nicely integrates mechanical and engineering procedures to access the nanoscale in a rational way. 

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