A Flexible, Wearable, Humidity‐Resistant and Self‐Powered Sensor Fabricated by Chitosan‐Critic Acid Film and its Applications in Human Motion Monitoring and Energy Harvesting

Abstract

Abstract Being a resource‐abundant natural material, chitosan shows good frictional electrical properties and has become one of the most used materials for triboelectric nanogenerators (TENGs). To improve water resistance and mechanical properties, herein, a strategy is proposed to modify the chitosan film by citric acid. The results show that both humidity‐resistant and mechanical properties of the modified films can be notably enhanced due to the formation of a network structure between chitosan molecular chains. Excellent output performance of 77.5 V and 2.66 µA is achieved in the TENG based on the modified film with a mass ratio of chitosan/citric acid = 3:1. Under a relative humidity (RH) of 80%RH, it can output 70.16% of the voltage compared to that under 20%RH. Self‐powered tactile sensor based on the TENG exhibits a sensitive response to pressure and bending and humidity resistance, giving the sensor tremendous promise for a wider range of human motion monitoring and energy harvesting.

Keywords

• chitosan
• cross‐link
• humidity‐resistant
• triboelectric nanogenerator