Cellulose enhanced highly sensitive and durable dual-network ionogel sensor for human motion monitoring

Abstract

Conductive gels are crucial in developing today’s flexible wearable technologies and have attracted widespread attention. However, achieving a harmonious balance among mechanical, sensing performance, and other functions still poses a significant challenge. This study designed an ionic liquid/poly (N, N-dimethylacrylamide-methacrylic acid-acrylamide)/cellulose (BPC) ionogel ternary system. The BPC ionogels exhibited excellent adhesion (47.18 kPa), self-healing capabilities, electrical conductivity, and mechanical properties including tensile strength (0.48 MPa), and elongation at break (899.69 %). In addition, the BPC ionogels have been proven suitable for making highly sensitive strain and temperature sensors, which could accurately identify human joint bending dynamics and facial micro-expression changes. It was characterized by fast response speed (140 ms), high sensitivity (strain sensitivity: 3.95–11.82, temperature sensitivity: 4.25 %/℃), and excellent cycle stability. When the BPC ionogel was customized into a capacitive pen, it could achieve smooth and delicate drawing operations on a smart touch screen. In summary, the BPC ionogels designed in this study demonstrate great potential in wearable electronic devices and human–computer interaction.