pH-Responsive Sponges Fabricated by Ag–S Ligands Possess Smart Double-Transformed Superhydrophilic–Superhydrophobic–Superhydrophilic Wettability for Oil–Water Separation
mediaposted on 06.10.2017, 00:00 by Jiahong Guo, Jikui Wang, Yihan Gao, Jie Wang, Wenbo Chang, Siyuan Liao, ZiMing Qian, YaXin Liu
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.