title: Directional wetting in anisotropic inverse opals.
abstract: Porous materials display interesting transport phenomena due to restricted motion of fluids within the nano- to microscale voids. Here, we investigate how liquid wetting in highly ordered inverse opals is affected by anisotropy in pore geometry. We compare samples with different degrees of pore asphericity and find different wetting patterns depending on the pore shape. Highly anisotropic structures are infiltrated more easily than their isotropic counterparts. Further, the wetting of anisotropic inverse opals is directional, with liquids filling from the side more easily. This effect is supported by percolation simulations as well as direct observations of wetting using time-resolved optical microscopy.
authors.affiliation: Department of Chemistry and Chemical Biology, ‡School of Engineering and Applied Sciences, and ∥Wyss Institute for Biologically Inspired Engineering, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: Katherine R
authors.initials: KR
authors.lastname: Phillips
authors.forename: Nicolas
authors.initials: N
authors.lastname: Vogel
authors.forename: Ian B
authors.initials: IB
authors.lastname: Burgess
authors.forename: Carole C
authors.initials: CC
authors.lastname: Perry
authors.forename: Joanna
authors.initials: J
authors.lastname: Aizenberg
mesh_terms: D016880:Anisotropy; D016062:Porosity; D017155:Wettability