Direct Patterning of Carbon Nanotube via Stamp Contact Printing Process for Stretchable and Sensitive Sensing Devices

Highlights

• A dry transfer method for the mass production of transparent conductive carbon nanotube (CNT) films inspired by typography has been proposed.

• The strain sensors based on the CNT films have high stretchability and repeatability (gauge factor up to 9960 at 85% strain).

• These ultrathin strain sensors can detect human motion, sound, and pulse, suggesting promising application prospects in wearable devices.

Electronic supplementary material

The online version of this article (10.1007/s40820-019-0323-8) contains supplementary material, which is available to authorized users.

Abstract

Flexible and wearable sensing devices have broad application prospects in bio-monitoring such as pulse measurement, motion detection and voice recognition. In recent years, many significant improvements had been made to enhance the sensor’s performance including sensitivity, flexibility and repeatability. However, it is still extremely complicated and difficult to prepare a patterned sensor directly on a flexible substrate. Herein, inspired by typography, a low-cost, environmentally friendly stamping method for the mass production of transparent conductive carbon nanotube (CNT) film is proposed. In this dry transfer strategy, a porous CNT block was used as both the seal and the ink; and Ecoflex film was served as an object substrate. Well-designed CNT patterns can be easily fabricated on the polymer substrate by engraving the target pattern on the CNT seal before the stamping process. Moreover, the CNT film can be directly used to fabricate ultrathin (300 μm) strain sensor. This strain sensor possesses high sensitivity with a gauge factor (GF) up to 9960 at 85% strain, high stretchability (> 200%) and repeatability (> 5000 cycles). It has been used to measure pulse signals and detect joint motion, suggesting promising application prospects in flexible and wearable electronic devices.

Electronic supplementary material

The online version of this article (10.1007/s40820-019-0323-8) contains supplementary material, which is available to authorized users.