Nature-inspired catechol-silicon complexation for robust superspreading and efficient crude oil recovery in high-salinity environments

Superspreading occurs when the liquid-surface interaction becomes sufficiently strong to overcome the liquid's surface tension, as evidenced by a contact angle approaching 0°. Conventional superspreading relies on complex designed artificial or biological surfaces, or external stimuli, which renders it challenging to exert its efficacy in common scenarios. Herein, inspired by mussel adhesion to rocks, we introduced a strategy utilizing catechol-based compounds that demonstrate strong silicate binding in saline environments, effectively modulating liquid-liquid-solid wettability at the molecular scale. Under mildly basic conditions, catechol induces a stable hydrated layer on the silicate surface, increasing the surface charge and facilitating the dewetting of oil during spreading. The strong interaction between catechol and silicon overcomes the van der Waals forces between silicate and crude oil, enabling efficient oil displacement. Moreover, we demonstrate that polyphenol-treated surfaces perform better in high-salinity environments, where surfactants lose effectiveness due to agglomeration caused by calcium ion. In contrast, polyphenol-based composite agents achieve a 70 % crude oil recovery in oil sand separation and a 90 % recovery in core flooding tests. The study demonstrates the potential of polyphenol‑silicon complexation for cost-effective, scalable superspreading applications in oil recovery and contamination management, highlighting its robust salt tolerance and promising industrial relevance.