Light-powered tumbler movement of graphene oxide/polymer nanocomposites.

Photoresponsive lamina and flexible graphene oxide/polymer nanocomposite films were fabricated using a simple solution casting method. Fast, stable, and reversible photomechanical behavior of the nanocomposite films upon irradiation with visible light was observed based on the photothermal effect of graphene oxide and the shape memory effect of the polymer matrix. According to the principle of equilibrium apparatus, light-powered tumbler movement was achieved in these films by imitating the structure of a wobbly man. Although photodriven contraction, expansion, bending, twisting, oscillation, and cilia movement have been realized in photomechanical materials, novel forms of complicated motion are still a bottleneck problem limiting their practical applications. This work would have a significant impact on photomechanical materials in device applications for advanced functions.