pH-Responsive Sponges Fabricated by Ag–S Ligands Possess Smart Double-Transformed Superhydrophilic–Superhydrophobic–Superhydrophilic Wettability for Oil–Water Separation

• Published in: ACS sustainable chemistry & engineering Vol. 5; no. 11; pp. 10772 - 10782
• Main Authors: Guo, Jiahong, Wang, Jikui, Gao, Yihan, Wang, Jie, Chang, Wenbo, Liao, Siyuan, Qian, ZiMing, Liu, YaXin
• Format: Journal Article
• Language: English
• Published: American Chemical Society 06.11.2017
• Subjects: Thiol modification; Sponge; Oil−water separation; Double transformed; pH-responsive
• ISSN: 2168-0485; 2168-0485
• DOI: 10.1021/acssuschemeng.7b02734

Advanced applications of surfaces with smart wettability offer great perspectives to design novel materials. pH-responsive smart sponges with double transformation are fabricated via in situ decoration of Ag nanoparticles through an oxidation–reduction reaction and followed by modification with a mixed thiol–ethanol solution containing HS­(CH2)11CH3, HS­(CH2)10COOH, and HS­(CH2)11OH. The wettability of sponges with optimal thiol proportions can switch reversibly between superhydrophilicity–superhydrophobicity–superhydrophilicity under different pH conditions. In addition, the as-prepared sponges have excellent absorption capacity and high oil–water separation efficiency (99.1%). This report provides a simple approach to prepare smart sponges with switchable wettability which can be further applied to many practical applications, such as marine purification and an oil–water on–off switch.