Regenerated Silk Fibroin-Modified Soft Graphene Aerogels for Supercapacitive Stress Sensors

Abstract

The regenerated silk fibroin is developed to soft graphene aerogels for application in stress sensor. The resultant graphene aerogel owns a low density of 14.1 mg cm−3 with high mass specific capacitance of 128.4 F g−1. When a single aerogel serving as elastic medium, a supercapacitive stress sensor is established to offer high sensitivity of 0.73 kPa−1 in ranging 0.01–10 kPa. In contract, the sensor based on original graphene aerogel just shows a sensitivity of 0.04 kPa−1. Further, the sensing stability of the optimized sensor can retain 87% under constant pressure intensity of 1 kPa for 1000 cycles. The soft effect can be attributed to the regenerated silk fibroin by intercalation in preparation, and the simulated results show that the stress response originated from the variation of ion concentration in the electrochemical system.