All-biomass flexible sensor based on lignin carbon nanospheres/cellulose for human motion detection

Flexible sensors have garnered significant interest because of their exceptional flexibility and strong integration capabilities with human skin, while the development of flexible sensors made from all-biomass materials remains a formidable task. Herein, an all-biomass sensor consisting of cellulose and lignin carbon nanospheres with certain sensitivity and excellent sensing properties was prepared by a simple filtration technique. The results showed that strong interfacial interactions were formed inside the prepared sensor, which could adapt to the dynamic adhesion requirements of deformable skin. As the strain sensor, it possessed an extremely short strain detection response time (0.3 s), a strain coefficient of 14.8, and maintained excellent stability after more than 5000 flexion-nonflexion cycles. As the pressure sensor, it offered a wide detecting range (0-1000 kPa), adequate sensitivity (0.038 kPa^-1 (0-300 kPa), 0.021 kPa^-1 (300-1000 kPa), and a fast reaction time (0.2 s). Furthermore, the sensor was not only environmentally friendly, and comfortable applied to all parts of the human body, but also demonstrated significant potential for wireless wearable devices. The all-biomass-based sensor had the potential to provide an effective way for reconfiguring biomass nanoparticles as well as a dependable, cost-effective, and environmentally responsible solution for electronic device technology.