PH Oscillator-Driven Jellyfish-like Hydrogel Actuator with Dissipative Synergy between Deformation and Fluorescence Color Change.

Abstract

Development of soft actuators with complex practical functions is significant for imitating the behaviors of living organisms. However, it is still a challenge to fabricate artificial soft actuators with jellyfish-like synergistic deformation and fluorescence color change (SDFC) and autonomous dynamic behavior, but such a system could obviously endow the classic soft actuators with more functions. Herein, we proposed to utilize tetra(4-pyridylphenyl)ethylene (TPE-4N) luminogen with pH-responsive aggregation-induced emission (AIE) to fabricate the AIE active hydrogel, which could be further employed to obtain an anisotropic bilayer soft actuator based on strong interfacial adhesion with acrylic acid (AA) gels. Furthermore, artificial flower-shape actuators showing SDFC behaviors were demonstrated. On the basis of these findings, jellyfish-inspired autonomous gel actuators driven by a pH oscillator have been fabricated, in which periodical SDFC behaviors completely regulated by the system itself without repetitive on/off switches of external stimuli were well synchronized with the pH oscillator. The described combination of nonlinear chemistry and responsive hydrogels actuator opens pathways toward out-of-equilibrium SDFC devices with autonomous behavior useful for biomimetic fields.