title: Biomimetic creation of hierarchical surface structures by combining colloidal self-assembly and Au sputter deposition.
abstract: Surfaces of hexagonally packed silica spheres have been functionalized with silanes containing different hydrocarbon or fluorocarbon chains. The resulting chemical and physical structures were studied to establish the effect of surface hydrophobicity on the measured contact angles on the rough surfaces. The results were used to assess the effects of surface modifications on the parameters in the Cassie equation. To achieve superhydrophobicity via a biomimetic approach, we created two-scale structures by first forming hexagonally packed SiO2 spheres, followed by Au deposition on the spheres and heat treatment to form Au nanoparticles on sphere surfaces. Contact angles over 160 degrees were achieved. This work provides improved understanding of the effect of the surface roughness and solid surface fraction on superhydrophobicity.
authors.affiliation: Department of Chemical and Biomolecular Engineering, Georgia Institute of Technology, 771 Ferst Drive, Atlanta, Georgia 30332-0245, USA.
authors.forename: Yonghao
authors.initials: Y
authors.lastname: Xiu
authors.forename: Lingbo
authors.initials: L
authors.lastname: Zhu
authors.forename: Dennis W
authors.initials: DW
authors.lastname: Hess
authors.forename: C P
authors.initials: CP
authors.lastname: Wong
mesh_terms: D032701:Biomimetics; D003102:Colloids; D006046:Gold / Q000737:chemistry* / Q000145:classification; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D010316:Particle Size; D012822:Silicon Dioxide / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature
chemical_list: D003102:Colloids; D006046:Gold; D012822:Silicon Dioxide