NIRT: Nanometer Stoichiometric Particle Compound Solutions and Control of their

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NIRT Nanometer Stoichiometric Particle Compound
Solutions and Control of their Self-Assembly
into the Condensed Phase Chris Sorensen, C.
Aakeröy, A. Chakrabarti, K. Klabunde and B.
Law Departments of Physics and Chemistry, Kansas
State University

• Goals
• Synthesize a library of monodisperse functional
  nanoparticles (NP).
• Study NP solution phase behavior and nucleation.
• Controlled assembly of NP into 2d and 3d
  superlattices and gels.
• Study NP solution surface and interfacial
  properties.
• 1. Synthesis

3. NP-NP Interactions
2. Solution Phase and Nucleation

• Core-core
• Core-ligand
• Ligand-ligand
• All mediated by the solvent

Solvated Metal Atom Dispersion Reactor
One phase individual, dissolved 5.5nm NPs.
Two phase clusters of NPs.
Au/C12SH NP (5.5nm) colloidal solution at
different temperatures, solvent t-butyltoluene
2-butanone. The phase transition is
reversible!
Static and dynamic light scattering to observe
cluster formation via nucleation as quench NP
solution from one phase to two.
x 1.3 is found in Au/C12SH NP superlattices.
4. Surface Interactions
Deep quench yields lots of small clusters,
shallow quench a few big clusters.
Droplets of Au/3-mercapto-1, 2-propanediol NP in
H2O on glass. Left no NP, contact angle 7o
right with NP, contact angle 23o.
Fat Fractals Solution of Au/SHC11COOH in DMSO
yields fractal/superlattice hybrid, with hydrogen
bonds when quenched.
NPs of Au, Ag, CdSe, In. Dia. 4 to
10nm Ligands. Nonfunctionalized CnSH, CnNH2,
P(C8)3 Functionalized HSCnCOOH, HSCnOH, HSCn
polyols
bis(8-imidazol-1-yloctyl)disulfide
Solvents toluene, t-butyltoluene, 2-butanone,
CH3OH, water, DMSO.
NPs affect wetting.