title: Nanoparticle-Mediated, Light-Induced Phase Separations.
abstract: Nanoparticles that both absorb and scatter light, when dispersed in a liquid, absorb optical energy and heat a reduced fluid volume due to the combination of multiple scattering and optical absorption. This can induce a localized liquid-vapor phase change within the reduced volume without the requirement of heating the entire fluid. For binary liquid mixtures, this process results in vaporization of the more volatile component of the mixture. When subsequently condensed, these two steps of vaporization and condensation constitute a distillation process mediated by nanoparticles and driven by optical illumination. Because it does not require the heating of a large volume of fluid, this process requires substantially less energy than traditional distillation using thermal sources. We investigated nanoparticle-mediated, light-induced distillation of ethanol-H2O and 1-propanol-H2O mixtures, using Au-SiO2 nanoshells as the absorber-scatterer nanoparticle and nanoparticle-resonant laser irradiation to drive the process. For ethanol-H2O mixtures, the mole fraction of ethanol obtained in the light-induced process is substantially higher than that obtained by conventional thermal distillation, essentially removing the ethanol-H2O azeotrope that limits conventional distillation. In contrast, for 1-propanol-H2O mixtures the distillate properties resulting from light-induced distillation were very similar to those obtained by thermal distillation. In the 1-propanol-H2O system, a nanoparticle-mediated, light-induced liquid-liquid phase separation was also observed.
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Physics and Astronomy, §Department of Civil and Environmental Engineering, ∥Department of Mechanical Engineering, ⊥Department of Chemistry, and #Laboratory for Nanophotonics and the Smalley-Curl Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Oara
authors.initials: O
authors.lastname: Neumann
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Physics and Astronomy, §Department of Civil and Environmental Engineering, ∥Department of Mechanical Engineering, ⊥Department of Chemistry, and #Laboratory for Nanophotonics and the Smalley-Curl Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Albert D
authors.initials: AD
authors.lastname: Neumann
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Physics and Astronomy, §Department of Civil and Environmental Engineering, ∥Department of Mechanical Engineering, ⊥Department of Chemistry, and #Laboratory for Nanophotonics and the Smalley-Curl Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Edgar
authors.initials: E
authors.lastname: Silva
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Physics and Astronomy, §Department of Civil and Environmental Engineering, ∥Department of Mechanical Engineering, ⊥Department of Chemistry, and #Laboratory for Nanophotonics and the Smalley-Curl Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Ciceron
authors.initials: C
authors.lastname: Ayala-Orozco
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Physics and Astronomy, §Department of Civil and Environmental Engineering, ∥Department of Mechanical Engineering, ⊥Department of Chemistry, and #Laboratory for Nanophotonics and the Smalley-Curl Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Shu
authors.initials: S
authors.lastname: Tian
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Physics and Astronomy, §Department of Civil and Environmental Engineering, ∥Department of Mechanical Engineering, ⊥Department of Chemistry, and #Laboratory for Nanophotonics and the Smalley-Curl Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Peter
authors.initials: P
authors.lastname: Nordlander
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Physics and Astronomy, §Department of Civil and Environmental Engineering, ∥Department of Mechanical Engineering, ⊥Department of Chemistry, and #Laboratory for Nanophotonics and the Smalley-Curl Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Naomi J
authors.initials: NJ
authors.lastname: Halas
keywords: azeotrope; distillation; ethanol; illumination; nanoparticles; propanol