Revealing the interfacial self-assembly pathway of large-scale, highly-ordered, nanoparticle/polymer monolayer arrays at an air/water interface.
The pathway of interfacial self-assembly of large-scale, highly ordered 2D nanoparticle/polymer monolayer or bilayer arrays from a toluene solution at an air/water interface was investigated using grazing-incidence small-angle scattering at a synchrotron source. Interfacial-assembly of the ordered nanoparticle/polymer array was found to occur through two stages: formation of an incipient randomly close-packed interfacial monolayer followed by compression of the monolayer to form a close-packed lattice driven by solvent evaporation from the polymer. Because the nanoparticles are hydrophobic, they localize exclusively to the polymer-air interface during self-assembly, creating a through thickness asymmetric film as confirmed by X-ray reflectivity. The interfacial self-assembly approach can be extended to form binary NP/polymer arrays. It is anticipated that by understanding the interfacial self-assembly pathway, this simple evaporative procedure could be conducted as a continuous process amenable to large area nanoparticle-based manufacturing needed for emerging energy technologies.
Department of Chemical and Nuclear Engineering, University of New Mexico/NSF Center for Micro-Engineered Materials, Albuquerque, New Mexico 87131, United States.
Shisheng
S
Xiong
Darren R
DR
Dunphy
Dan C
DC
Wilkinson
Zhang
Z
Jiang
Joseph
J
Strzalka
Jin
J
Wang
Yongrui
Y
Su
Juan J
JJ
de Pablo
C Jeffrey
CJ
Brinker