Sunlight-Drivable Composite Film Using Carbon Nanopowder-doped PVDF and Liquid Crystal Polymer Network

Actuators based on liquid crystals have garnered significant attention due to their potential applications in wearable technology and bionic soft robots. Composite films composed of liquid crystal polymer networks (LCNs) and other stimulus-responsive materials exhibit the capability to convert external stimuli into mechanical deformation. However, the development of sunlight-driven actuators presents significant challenges, primarily due to the relatively low intensity of sunlight and the limited conversion efficiency of photothermal materials. In this paper, we present a composite film fabricated using poly(vinylidene fluoride) doped with carbon nanopowders (PC) as a photothermal conversion material combined with a hybrid-alignment liquid crystal polymer network film. Under the midday sun during summer, the composite film is heated from room temperature to 74.5 °C quickly, resulting in a substantial angle change of 235°. Additionally, the actuators fabricated by this composite film can demonstrate phototactic and light-avoiding rolling behaviors. This sunlight-drivable composite film shows considerable promise for the research and development of bionic devices powered by natural light.