Organic-inorganic hybrid phyllosilicate with switchable wettability induced by ultrasonication treatment

Materials with switchable wettability have attracted much attention because of its potential use in various applications. In this report, a novel switchable hydrophilic/hydrophobic organic-inorganic hybrid phyllosilicate was prepared by the self-assembly of vinyltriethoxysilane and calcium chloride. The structure of the hybrid phyllosilicate was a framework consisted of a calcium‑oxygen octahedral sheet sandwiched between two vinyl-silica tetrahedron sheets. The water contact angle (CA) at hydrophobic and hydrophilic states of hybrid phyllosilicate was 140.4° and 49.2°, respectively. The absorbed oil by hybrid phyllosilicate can be reversibly released in water after ultrasonication treatment for 30 min. On the surface of hybrid phyllosilicate, hydrophobic state of nanoflower (100–300 nm) morphology was switched to hydrophilic state of nanosheets (5–20 μm) after ultrasonication treatment. This novel structure of hybrid phyllosilicate expands the architecture concept for materials with controllable wettability, which can be applied in the construction of functional films, microfluidic switching, and ultrasonic responsive devices.