A universal approach to create non-wettable surfaces by UV-grafting of PDMS with various functional groups to form liquid-infused slippery surfaces on solid substrates

• Applicant: Dr. Alexander Tesler
• Subject Area: Synthesis and Properties of Functional Materials ; Coating and Surface Technology ; Solid State and Surface Chemistry, Material Synthesis
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 540989797

Despite centuries of efforts, wetting-related phenomena still greatly challenge modern society in terms of ecology, biodiversity, and safety. On one side, wetting is responsible for life on Earth, on the other, it deteriorates the desired functionality of materials leading to severe losses in GDP and human lives as well as influencing negatively the environment in terms of increased pollution. Yet, humanity can beneficially employ water-based resources to cover, for example, the need for sustainable and reliable energy utilizing the constant ocean movement. Nevertheless, this potential is insufficiently exploited because the aquatic environment is extremely challenging due to (i) the presence of ions such as chlorine, sulfur, and bromine causing enhanced corrosion of materials, and (ii) the accumulation of aquatic organisms that deteriorate normal functionality of devices. Anti-biofouling coatings that consist of biocidal compounds such as tributyltin had been banned in 2008. Nowadays, non-toxic antifouling coatings act to inhibit the adhesion of organisms and enhance fouling release (FR) without involving chemical reactions or toxic chemicals strictly vital. Recently, we developed a facile method to graft virtually any solid surface with a silicone-based liquid-infused slippery (LISS) coating without involving any pre- or post-grafting processes. The approach involves solely polydimethylsiloxane (PDMS) specifically activated by UVA light. PDMS is a biocompatible material used in a wide range of applications including food, marine, and biomedical fields. Here, we propose to further expand the LISS technology by introducing functional groups to PDMS such as fluorinated and PEGilated blocks as well as photocatalytic TiO2NPs to further increase the biofouling resistance, yet decrease surface wettability enhancing corrosion resistance. Our preliminary results demonstrate that the LISS technology performs as well as state-of-the-art SLIPS, while from the technological point of view, it is simplified and ready to be implemented in real applications.

• DFG Programme: Research Grants