All-Fiber Volatile Organics-Perceptive Actuators

Abstract

Soft robots with real-time volatile organic compound (VOC) perceptivity are promising for dynamic hazard detection. However, reconciling VOC-responsive actuation with an autonomous perception remains challenging. Inspired by Victoria amazonica, which blooms and closes with synchronous color change under environmental stimulations, we developed a solvatophore-induced solvatochromic-piezoelectric material by synthesizing a solvatochromic molecule-modified palygorskite-enhanced polyvinylidene difluoride and realized a VOC-responsive all-fiber actuator with solvatochromic and piezoelectric properties for cooperative visual and electrical perception of volatile organics. Under VOCs, the actuator exhibits bidirectional bending, obvious and stable color change, and characteristic piezoelectric output, allowing the identification of the type and concentration of the VOC. The solvatochromic-piezoelectric actuator demonstrates a large bending curvature of 4.63 cm^–1, an ultrafast response speed of up to 4.36 cm^–1 s^–1, and excellent stability of 1500 actuation cycles without fatigue, with synchronous VOC-induced piezoelectric output reflecting actuation conditions. VOC-responsive solvatochromic and piezoelectric sensing, manipulation, and robots were demonstrated as applications. The VOC-triggered soft robot demonstrates stable motion with synchronous piezoelectric output, capable of autonomously perceiving and responding to environmental VOC. This work presents a widely applicable interactive visual-electronic VOC detection strategy for safety, health, and environmental protection, which could also inspire the exploitation of high-performance responsive fiber materials.