Chunya Wang1 Qi Wang1 Yin Zhe1 Yingying Zhang1

1, Tsinghua University, Beijing, , China

The development of flexible electronics and equipment attracts significant interests in recent years. It is of great importance to explore low cost and scalable preparation approaches for high performance flexible and wearable electronics. Silkworm silk, with five thousand years’ usage history, is a popular natural material for clothes or wearing accessories. In this talk, I will present our work on exploring the application of silk fiber/fabrics in flexible electronics. We demonstrated that carbonized silk fabric with a plain-weave structure, based on its unique N-doped graphitic carbon nanostructure and the macroscale woven structure, could be worked as strain sensors with both of high sensitivity (gauge factor of 9.6 in the strain range of 0%-250% and 37.5 in the range of 250%-500%) and high tolerable strain (more than 500%). The as-obtained sensors have fast response (<30 ms) and high durability (>10,000 cycles). It was demonstrated that such strain sensors could be used for monitoring both of vigorous human motions (such as jumping, marching, jogging, bending and rotation of joints), subtle human motions (such as pulse, facial expression, respiration and phonation) and even sound, and further demonstrated the capture and reconstruction of human body movements with our sensors, showing their superior performance and tremendous potential applications in wearable electronics and intelligent robots. Besides, transparent electronics skins, elastic thermal therapy devices, stretchable wires and stretchable energy devices based on silk materials will also be demonstrated. These strategy paves new ways for the low cost and large scale fabrication of high performance wearable strain sensors.

Chunya Wang, Mingchao Zhang, Kailun Xia, Xueqin Gong, Huimin Wang, Zhe Yin, Baolu Guan, and Yingying Zhang*. Intrinsically Stretchable and Conductive Textile by a Scalable Process for Elastic Wearable Electronics. ACS Appl. Mater. Interfaces 2017, 9 (15), 13331–13338.
Qi Wang, Muqiang Jian, Chunya Wang, Yingying Zhang*. Carbonized silk nanofiber membrane for transparent and sensitive electronic skin. Advanced Functional Materials. 2017, 27,1605657.
Muqiang Jian, Kailun Xia, Qi Wang, Zhe Yin, Huimin Wang, Chunya Wang, Huanhuan Xie, Mingchao Zhang, and Yingying Zhang*. Flexible and Highly Sensitive Pressure Sensors Based on Bionic Hierarchical Structures. Advanced Functional Materials. 2017, 27,1606066.
Mingchao Zhang, Chunya Wang, Huimin Wang, Muqiang Jian, Xiangyang Hao*, Yingying Zhang*. Carbonized Cotton Fabric for High Performance Wearable Strain Sensors Advanced Functional Materials 2017, 27, 1604795.
Chunya Wang, Xiao Li, Enlai Gao, Muqiang Jian, Kailun Xia, Qi Wang, Zhiping Xu, Tianling Ren, Yingying Zhang*. Carbonized Silk Fabric for Ultra-stretchable, Highly Sensitive and Wearable Strain Sensors. Advanced Materials 2016, 28, 6640.