Dynamic/static mechanical stimulation double responses and self-powered “green” electronic skin based on electrode potential difference

Abstract

• Self-powered electronic skin based on electrode potential difference can respond to dynamic/static mechanical stimulation. • The device can be prepared by simple, efficient and low-cost screen printing. • The use of water-soluble and biodegradable materials enables devices to be environmentally friendly during manufacturing and disposal. Low-power or self-powered electronic skin (e-skin) is considered an important research area, as it reduces the requirements for stable energy sources in electronic systems. However, most reported self-powered e-skins can only detect dynamic mechanical stimuli, but cannot detect ubiquitous static mechanical stimuli, resulting in a significant amount of information loss. In this paper, we report a self-powered e-skin based on electrode potential difference that can detect dynamic/static mechanical stimuli with sensitivity and response time of 399 mV/kPa and 85 ms, respectively. In this device, the mechanical stimulus is converted into a voltage signal by regulating the impedance of the electrode/electrolyte interface. In the process of preparing the device, a “green” electrode ink was prepared using a water-soluble, biodegradable polymer as the binder of the active material. Owing to the printability of the ink, a patterned electrode can be formed on a flexible substrate using low-cost screen-printing technology. Finally, we designed a co-planar shared electrode structure, which effectively reduced the complexity of the circuit layout. This new device has been successfully used for information acquisition of objects and detection of physiological signals, and we believe it has significant implications for the future development of e-skins.