Stretchable CNTs-Ecoflex Composite as Variable-Transmittance Skin for Ultrasensitive Strain Sensing

Wireless controlled flexible electronic devices are going to be the key components in various technologies toward sustainable advancement of the society in future. However, most of the currently available conventional sensing devices, which usually comprise complex structures and the integration of stretchability, face a lot of difficulties to satisfy the comprehensive demands. Here, a new fabrication method is demonstrated for integration of carbon nanotubes (CNTs) and stretchable silicone film into a sandwich structure, in which the transmittance can be significantly controlled via externally applied strain. The transmittance change can, in turn, also be exploited to distinguish the applied strain. The proposed sandwich structure significantly enhances the stretchability of the CNTs networks, endowing the sensor with a strain sensitivity as high as 70.2 and a wide reliable strain sensing range up to 400%. The proposed CNTs based flexible device fabrication concept is simple and cost-effective which can be easily up scaled toward promising applications in wireless weight sensing, interactive wearable devices, smart robots, and other advanced technologies.