Self-assembly of gold nanoparticles at the oil-vapor interface: From mono- to multilayers

Journal
Langmuir : the ACS journal of surfaces and colloids  
Volume
30
Issue
44
Start Page
13176
End Page
13181
Citation
Langmuir 30 (44): 13176-13181 (2014-11-11)
Publisher DOI
10.1021/la503551d
Scopus ID
2-s2.0-84911447116
Alkylthiol-coated gold nanoparticles spontaneously segregate from dispersion in toluene to the toluene-vapor interface. We show that surface tension drops during segregation with a rate that depends on particle concentration. Mono- and multilayers of particles form depending on particle concentration, time, and temperature. X-ray reflectometry indicates fast monolayer formation and slow multilayer formation. A model that combines diffusion-limited segregation driven by surface energy and heterogeneous agglomeration driven by dispersive van der Waals particle interactions is proposed to describe film formation.