title: Superhydrophobic and Slippery Lubricant-Infused Flexible Transparent Nanocellulose Films by Photoinduced Thiol-Ene Functionalization.
abstract: Films comprising nanofibrillated cellulose (NFC) are suitable substrates for flexible devices in analytical, sensor, diagnostic, and display technologies. However, some major challenges in such developments include their high moisture sensitivity and the complexity of current methods available for functionalization and patterning. In this work, we present a facile process for tailoring the surface wettability and functionality of NFC films by a fast and versatile approach. First, the NFC films were coated with a layer of reactive nanoporous silicone nanofilament by polycondensation of trichlorovinylsilane (TCVS). The TCVS afforded reactive vinyl groups, thereby enabling simple UV-induced functionalization of NFC films with various thiol-containing molecules via the photo "click" thiol-ene reaction. Modification with perfluoroalkyl thiols resulted in robust superhydrophobic surfaces, which could then be further transformed into transparent slippery lubricant-infused NFC films that displayed repellency against both aqueous and organic liquids with surface tensions as low as 18 mN·m-1. Finally, transparent and flexible NFC films incorporated hydrophilic micropatterns by modification with OH, NH2, or COOH surface groups, enabling space-resolved superhydrophobic-hydrophilic domains. Flexibility, transparency, patternability, and perfect superhydrophobicity of the produced nanocellulose substrates warrants their application in biosensing, display protection, and biomedical and diagnostics devices.
authors.forename: Jiaqi
authors.initials: J
authors.lastname: Guo
authors.forename: Wenwen
authors.initials: W
authors.lastname: Fang
authors.affiliation: Institute of Functional Interfaces, Karlsruhe Institute of Technology and Karlsruhe Nano Micro Facility, Karlsruhe Institute of Technology , 76021 Karlsruhe, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Welle
authors.affiliation: Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT) , 76344 Eggenstein-Leopoldshafen, Germany.
authors.forename: Wenqian
authors.initials: W
authors.lastname: Feng
authors.forename: Ilari
authors.initials: I
authors.lastname: Filpponen
authors.forename: Orlando J
authors.initials: OJ
authors.lastname: Rojas
authors.affiliation: Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT) , 76344 Eggenstein-Leopoldshafen, Germany.|Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT) , 76021 Karlsruhe, Germany.
authors.forename: Pavel A
authors.initials: PA
authors.lastname: Levkin
keywords: SLIPS; nanocellulose; photochemistry; slippery lubricant-infused porous surface; superhydrophobicity; surface patterning; thiol−ene reaction