In-situ characterization of colloidal soft solution processes.

Technical Report · Sat Nov 01 04:00:00 EST 2003

DOI:https://doi.org/10.2172/918371· OSTI ID:918371

Tallant, David Robert; Rodriguez, Mark Andrew; Bell, Nelson Simmons

The purpose of this program was to investigate methods to characterize the colloidal stability of nanoparticles during the synthesis reaction, and to characterize their organization related to interparticle forces. Studies were attempted using Raman spectroscopy and ultrasonic attenuation to observe the nucleation and growth process with characterization of stability parameters such as the zeta potential. The application of the techniques available showed that the instrumentation requires high sensitivity to the concentration of the system. Optical routes can be complicated by the scattering effects of colloidal suspensions, but dilution can cause a lowering of signal that prevents collection of data. Acoustic methods require a significant particle concentration, preventing the observation of nucleation events. Studies on the dispersion of nanoparticles show that electrostatic routes are unsuccessful with molecular surfactants at high particle concentration due to electrostatic interaction collapse by counterions. The study of molecular surfactants show that steric lengths on the order of 2 nm are successful for dispersion of nanoparticle systems at high particle concentration, similar to dispersion with commercial polyelectrolyte surfactants.

• Research Organization: Sandia National Laboratories
• Sponsoring Organization: USDOE
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 918371
• Report Number(s): SAND2003-3868
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
COLLOIDS
ELECTROSTATICS
MEASURING METHODS
NANOSTRUCTURES
NUCLEATION
STABILITY
SURFACE POTENTIAL
SURFACTANTS
SYNTHESIS