title: Anisotropic Janus Si nanopillar arrays as a microfluidic one-way valve for gas-liquid separation.
abstract: In this paper, we demonstrate a facile strategy for the fabrication of a one-way valve for microfluidic (MF) systems. The micro-valve was fabricated by embedding arrays of Janus Si elliptical pillars (Si-EPAs) with anisotropic wettability into a MF channel fabricated in poly(dimethylsiloxane) (PDMS). Two sides of the Janus pillar are functionalized with molecules with distinct surface energies. The ability of the Janus pillar array to act as a valve was proved by investigating the flow behaviour of water in a T-shaped microchannel at different flow rates and pressures. In addition, the one-way valve was used to achieve gas-liquid separation. We believe that the Janus Si-EPAs modified by specific surface functionalization provide a new strategy to control the flow and motion of fluids in MF channels.
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, P. R. China. zjh@jlu.edu.cn.
authors.forename: Tieqiang
authors.initials: T
authors.lastname: Wang
authors.forename: Hongxu
authors.initials: H
authors.lastname: Chen
authors.forename: Kun
authors.initials: K
authors.lastname: Liu
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.forename: Peihong
authors.initials: P
authors.lastname: Xue
authors.forename: Ye
authors.initials: Y
authors.lastname: Yu
authors.forename: Shuli
authors.initials: S
authors.lastname: Wang
authors.forename: Junhu
authors.initials: J
authors.lastname: Zhang
authors.forename: Eugenia
authors.initials: E
authors.lastname: Kumacheva
authors.forename: Bai
authors.initials: B
authors.lastname: Yang