The graphene sandwich structure flexible strain sensor for health monitoringa

In recent years, the rapid development of flexible wearable electronic devices, particularly in the fields of human health monitoring and human-computer interaction, has made flexible sensors a hot research topic, with flexible pressure sensors being the most widely used. However, many flexible pressure sensors face issues such as complex preparation processes, high production costs, and poor overall performance. Therefore, there is a rapidly increasing demand for flexible pressure sensors with excellent performance, simple preparation processes, and low manufacturing costs in fields such as health monitoring and human motion signal monitoring. In this study, a simple and efficient lamination method was proposed to encapsulate graphene film in Ecoflex, preparing a flexible Ecoflex/Graphene/Ecoflex strain sensor with a sandwich structure. The sensor exhibits excellent strain sensing performance, with a GF of 27.46 in the 0.5 %-30 % strain range and a GF of 132.83 in the 30 %-50 % strain range. The sensor has a wide measurement range of 0–80 %, a fast response time of 111 ms, and excellent repeatability and stability. Due to its excellent performance, the Ecoflex/ Graphene/Ecoflex flexible strain sensor easily monitors motion signals from the human face (between the eyebrows) and major joints (finger joints, wrist joints, elbow joints, and knee joints). It also achieves wireless transmission of monitoring data, demonstrating great application prospects in flexible wearable devices, human health monitoring, and human-computer interaction fields.