Superhydrophobic and Multifunctional Aerogel Enabled by Bioinspired Salvinia Leaf‐Like Structure

• Published in: Advanced functional materials 2022-04, Vol.32 (14), p.n/a
• Main Authors: Zhang, Xinhai, Lei, Yang, Li, Chenxi, Sun, Gang, You, Bo
• Format: Article
• Language: English
• Subjects: Absorption; aerogel; Aerogels; aramid‐polyimide nanocomposite; biomimetic; Biomimetic materials; Chemists; Compressive properties; Contact angle; Hydrophobic surfaces; Hydrophobicity; Materials science; Modulus of elasticity; Nanocomposites; Nanoparticles; separation; Siloxanes; superhydrophobic; Surface chemistry; Thermal conductivity
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202110830

The biomimetic exploration of functionalized materials is still of great importance to chemists and materials scientists, although the majority of the ingenious structures and functions of organisms are not simulated precisely. Here, taking inspiration from the strongly hydrophobic properties of the Salvinia leaf, a novel superhydrophobic and multifunctional aramid‐polyimide nanocomposite aerogel with Salvinia leaf‐like structures is fabricated (abbreviated to Bio‐ANFPI aerogel). The Bio‐ANFPI‐1 aerogel surface is covered with many of the generated spherical and hemispherical silica nanoparticles by a in situ siloxane polycondensation method, analogous to the Salvinia leaf surface, which facilitates the construction of the superhydrophobic aerogels (Bio‐ANFPI‐2) based on the Cassie‐Baxter model. It is found that the maximum stress and compressive modulus of the Bio‐ANFPI‐2 aerogel are improved by 174% and 245%, respectively. Further, the Bio‐ANFPI‐2 aerogel exhibits superhydrophobicity, with a water contact angle of 152° and a rolling angle of 8.3°. In addition, the aerogels possess a low thermal conductivity, excellent metal ion absorption capacity, and impressive absorption capacity of oil that maintained its initial value at ≈80% after 50 cycles at 88% compression. Overall, this work can enable a more general and practical manner of fabricating biomimetic high‐performance lightweight materials. An in situ siloxane polycondensation method is devised to mimic the microstructure of Salvinia leaf for the construction of the biomimetic aerogels. The generated silica nanoparticles are fixed in the aramid‐polyimide composite aerogel by the polyorganosiloxane film, thus realizing the combined action of the micro‐nanostructures and the low surface energy chemical to construct superhydrophobic aerogels with multifunctionality.