Temporally Anticorrelated Motion of Nanoparticles at a Liquid Interface.
Quantum dots at the hexane-glycerol interface exhibited unexpected behavior including highly dynamic adsorption/desorption, where the lateral nanoparticle motion was anomalously fast immediately after adsorption and prior to desorption. At the interface, particles exhibited pseudo-Brownian lateral motion, in which the instantaneous diffusion coefficient was temporally anticorrelated, in agreement with our simulations involving fractional Brownian motion in the surface-normal direction. These phenomena suggest that, in contrast to the conventional picture for colloidal particles, nanoparticles explore a landscape of metastable interfacial positions, with different exposures to the two adjacent phases.
Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80309, United States.
Dapeng
D
Wang
Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80309, United States.
Renfeng
R
Hu
Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80309, United States.
Michael J
MJ
Skaug
Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80309, United States.
Daniel K
DK
Schwartz
Brownian motion; anticorrelation; interfacial diffusion; nanoparticles