Light-powered soft actuator doped with different shaped tungsten oxide (W18O49) nanostructures: The role of shape

Addressing the challenge of enhancing the performance and broadening the applications of light-driven soft actuators is a major concern within the scientific community. One effective approach to tackle this issue involves incorporating appropriate materials into these actuators, a technique referred to as doping. Among the most promising candidates for creating such actuators are liquid crystal network (LCN) polymers, known for their reversible, programmable, and responsiveness to various stimuli, resulting in shape changes. By incorporating suitable materials into these networks through doping, valuable outcomes can be achieved. While previous studies have examined the impact of the nanostructures nature on the photo-responsive behavior of LCN polymers, none have specifically focused on the influence of their structural shape. Consequently, the primary objective of this study is to examine the significance of this crucial feature. This paper presents an investigation into the oscillation performance of a light-powered soft actuator constructed using W18O49-doped LCN polymers in two distinct shapes: urchin and wire. The analysis encompasses oscillation frequency, amplitude, elastic modulus, thermo-mechanical force, and curvature radius, revealing that the structural shape of the nanostructures plays a dominant role on the oscillatory behavior of LCN polymer.