(179w) Gold Nanoparticle Films with Varying Surface Roughness Obtained by A Gas-Expanded Liquid Deposition Process | AIChE

(179w) Gold Nanoparticle Films with Varying Surface Roughness Obtained by A Gas-Expanded Liquid Deposition Process



Alkanethiol-stabilized
gold nanoparticles (AuNPs) were deposited via a gas-expanded liquid (GXL)
technique utilizing CO2-expanded hexane onto different substrates.
The surfaces of the substrates were modified by coating silicon (100)
substrates with various organic self-assembled monolayers (SAMs). The films
were characterized and the rms surface roughness values were obtained to
determine the nanoparticle film deposition and growth characteristics. Based on
the critical surface tension of the SAMs, the film growth indicates a shift between
layer-by-layer deposition and island formation, which also results in a change in
the surface roughness. Moreover, the surface roughness is influenced by the
concentration of the nanoparticle solution, the average size, the size
distribution of AuNPs and the nature of the AuNP surface chemistry. The manner
in which the surface roughness was affected by each of the influences was
investigated and possible explanations for the results under different
conditions were developed. By varying the surface roughness, the real contact
surface area of the substrate will be changed as well. Therefore, the potential
exists to engineer nanoparticle films to provide reduction in adhesion that
occurs between surfaces due to interfacial forces of MEMS devices, and these
aspects will be discussed in detail.

See more of this Session: Interfacial Phenomena (Area 1c) Poster Session

See more of this Group/Topical: Engineering Sciences and Fundamentals