Synergistic fluorescent hydrogel actuators with selective spatial shape/color-changing behaviors via interfacial supramolecular assembly

Biomimetic intelligent polymeric hydrogel actuators with cooperative fluorescence-color switchable behaviors are expected to find great potential applications in soft robotics, visual detection/display, and camouflage applications. However, it remains challenging to realize the spatial manipulation of synergistic shape/color-changing behaviors. Herein, we report an interfacial supramolecular assembly (ISA) approach that enables the construction of robust fluorescent polymeric hydrogel actuators with spatially anisotropic structures. On the basis of this ISA approach, diverse 2D/3D soft fluorescent hydrogel actuators, including chameleon- and octopi-shaped ones with spatially anisotropic structures, were facilely assembled from two different fluorescent hydrogel building blocks sharing the same physically cross-linked agar network. Spatially control over synergistic shape/color-changing behaviors was then realized in one single anisotropic hydrogel actuator. The proposed ISA approach is universal and expected to open promising avenues for developing powerful bioinspired intelligent soft actuators/robotics with selective spatial shape/color-changing behaviors.