Cucurbit[8]uril‐Regulated Colloidal Dispersions Exhibiting Photocontrolled Rheological Behavior

In situ photocontrol over shear‐thickening of condensed colloidal dispersions is of paramount importance in a wide range of applications including process technology and photorheological fluids. Its development and practicability, however, are hampered by the lack of well‐designed photoresponsive systems. Here, a colloidal suspension whose rheological behavior is readily switchable between shear‐thinning and shear‐thickening using an external light stimulus is reported. This smart colloidal solution contains hybrid raspberry‐like colloids prepared by employing cucurbit[8]uril as a supramolecular linker to assemble functional Fe3O4 nanoparticles onto a silica core. The formed raspberry colloids are photoresponsive and can be reversibly disassembled under UV irradiation.