Counterion-Dictated Self-Cleaning Behavior of Polycation Coating upon Water Action: Macroscopic Dissection of Hydration of Anions
writer：Qi Tao, Dr. Shu Huang, Xu Li, Dr. Xue‐Feng Chu, Prof. Xiaolin Lu, Prof. Dayang Wang
keywords：Counterion, Self-Cleaning, Polycation Coating, Hydration of Anions
source：期刊
specific source：Angew. Chem. Int. Ed. 2020, 59, 14466–14472
Issue time：2020年
The counterions of polydiallyldimethylammonium (PDADMA) coatings were altered by incubation in aqueous solutions of different electrolytes. Oil de‐wetting on the resulting polycationic surfaces upon water action exhibited a straightforward connection with the Jones–Dole viscosity B‐coefficient (Bη) sign of surface counteranions. Upon water action, surface counteranions with negative Bη render PDADMA coatings oil‐adhering, but those with positive Bη furnish PDADMA coatings with excellent self‐cleaning. The oil‐adhering PDADMA surfaces can become self‐cleaning upon water action in response to the Bη of surface counteranions sign‐switching with increasing water temperature. Courtesy of surface counter‐anions with Bη>0, self‐cleaning PDADMA coatings enable not only conversion of conventional meshes into self‐cleaning membranes for oil/water separation, but also regioselective maneuver of oil flow on polycationic surfaces according to the Bη sign of surface counteranions patterned atop.
https://onlinelibrary.wiley.com/doi/10.1002/ange.202002819