Parallel Microcracks based Ultrasensitive and Highly Stretchable Strain Sensors

There is an increasing demand for flexible, skin-attachable, and wearable strain sensors due to their various potential applications. However, achieving strain sensors with both high
sensitivity and high stretchability is still a grand challenge. Here, we propose highly sensitive and stretchable strain sensors based on the reversible microcrack formation in composite thin
films. Controllable parallel microcracks are generated in graphite thin films coated on elastomer films. Sensors made of graphite thin films with short microcracks possess high
gauge factors (maximum value of 522.6) and stretchability (ε≥50%) whereas long microcracks based sensors show ultrahigh sensitivity (maximum value of 11,344), but with
limited stretchability (ε≤50%). We demonstrate the high performance strain sensing of our sensors in both small and large strain sensing applications such as human physiological
activity recognition, human body large motion capturing, vibration detection, pressure sensing, and soft robotics.

URL: http://pubs.acs.org/doi/abs/10.1021/acsami.5b12588