Interfacial-Modified Graphene/Cotton Fabric for Durable Pressure Sensor via Electrostatic Self-Assembly

Flexible, wearable pressure sensors have been widely studied in the fields of motion detection, health management, and human–computer interaction. However, the unsatisfactory stability and durability limit its application, due to the weak interface interaction between the flexible substrate and conductive layer. Herein, we design a wearable pressure sensor with good sensitivity and stability by integrating a conductive cellulose/exfoliated graphene (CEG) ink with polyethylenimine-modified cotton fabrics (PEI-CFs). The negatively charged graphene was obtained via liquid-phase exfoliation of graphite in a sustainable cellulose solution. The pressure sensor was prepared by an electrostatic self-assembly process in which negatively charged CEG is adsorbed to the positively charged PEI-CFs. In this strategy, CEG ink combines firmly with the PEI-CF substrate, endowing the as-prepared pressure sensor with stable sensing performance and long-term stability. Due to these advantages, it can be used for human health monitoring, such as human motion, breathing, and microexpression. This work provides a simple and feasible route for the development of stable, durable, and high-performance wearable electronics.