Facile fabrication of robust cork-inspired superhydrophobic aerogel for continuous oil spill and emulsion absorption

Abstract

Although superhydrophobic aerogels are widely used in oil–water separation, traditional vertical channel aerogels often struggle to achieve flexibility, robustness, and superhydrophobicity simultaneously. Inspired by cork wood, carboxylated nitrile rubber was selected as the soft phase, while a polymethylsiloxane layer served as the rigid phase, resulting in the successful preparation of a robust superhydrophobic aerogel. The aerogel featured a honeycomb-like structure with a multimodal pore size distribution. It exhibited excellent superhydrophobicity, with a contact angle of about 155.5° and a rolling angle of approximately 2°. Even under various extreme conditions, the aerogel maintained a contact angle exceeding 150°, showcasing excellent stability. Additionally, it showed excellent mechanical properties, with only around 10 % irreversible damage after 1000 compression cycles at 30 % strain. Therefore, the aerogel exhibited excellent adsorption performance, with an absorption capacity of 0.909 mL/cm³, and an average absorption rate of 0.848 mL/s. Even after 100 cycles, it retained excellent recovery capabilities, proving effective in various practical oil–water separation scenarios. Most importantly, this method was simple, easy to operate, customizable, and cost-effective, laying the foundation for widespread industrial applications.