Solvent-driven actuators based on soft Janus films of homogeneous composition

A Janus polymer film capable of rapid and reversible folding by triggering with organic solvents is prepared through a template method. Different from most self-folding films with layered structures of different compositions, the reported film can achieve folding function with just a single component by forming a Janus structure. The solvent-driven folding of the film can be remotely controlled not only in air but also in water. In addition, the film is easy to integrate with other materials to fabricate actuators with specific functions for diverse applications.