title: Ordered Micro/Nanostructures with Geometric Gradient: From Integrated Wettability "Library" to Anisotropic Wetting Surface.
abstract: Geometric gradients within ordered micro/nanostructures exhibit unique wetting properties. Well-defined and ordered microsphere arrays with geometric gradient (OMAGG) are successfully fabricated through combining colloidal lithography and inclined reactive ion etching (RIE). During the inclined RIE, the graded etching rates in vertical direction of etcher chamber are the key to generating a geometric gradient. The OMAGG can be used as an effective mask for the preparation of micro/nanostructure arrays with geometric gradient by selective RIE. Through this strategy, a well-defined wettability "library" with graded silicon cone arrays is fabricated, and the possibility of screening one desired "book" from the designated wettability "library" is demonstrated. Meanwhile, the silicon cone arrays with geometric gradient (SCAGG) can be applied to control the wetting behavior of water after being modified by hydrophilic or hydrophobic chemical groups. Based on this result, a temperature-responsive wetting substrate is fabricated by modifying poly n-isopropyl acrylamide (PNIPAM) on the SCAGG. These wettability gradients have great potential in tissue engineering, microfluidic devices, and integrated sensors.
authors.affiliation: State Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
authors.forename: Peihong
authors.initials: P
authors.lastname: Xue
authors.affiliation: State Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
authors.forename: Jingjie
authors.initials: J
authors.lastname: Nan
authors.affiliation: Research Center for Molecular Science and Engineering, Northeastern University, Shenyang, 111004, P. R. China.
authors.forename: Tieqiang
authors.initials: T
authors.lastname: Wang
authors.affiliation: State Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
authors.forename: Shuli
authors.initials: S
authors.lastname: Wang
authors.affiliation: State Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
authors.forename: Shunsheng
authors.initials: S
authors.lastname: Ye
authors.affiliation: State Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
authors.forename: Junhu
authors.initials: J
authors.lastname: Zhang
authors.affiliation: State Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
authors.forename: Zhanchen
authors.initials: Z
authors.lastname: Cui
authors.affiliation: State Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
authors.forename: Bai
authors.initials: B
authors.lastname: Yang
keywords: anisotropic wetting behavior; colloidal lithography; gradient materials; ordered micro/nanostructures; wettability “library”