Flexible cellulose-based hybrid nanogenerators for self-powered wearable bio-monitoring applications

Flexible hybrid nanogenerators (HNGs) have received significant attention for their potential in harvesting mechanical energy to power portable and miniaturized portable devices. This work presents a method to fabricate flexible, durable and biodegradable electrospun polydopamine@barium titanate/cellulose acetate (PDA@BTO/CA) nanofiber films. This design integrates polydopamine (PDA) and piezoelectric barium titanate (BTO) nanoparticles within a flexible cellulose acetate (CA) matrix to enable self-powered wearable biomonitoring. The inclusion of PDA enhances the physical adhesion between BTO and CA, resulting in a significant 40% increase in voltage output. Notably, the PDA-modified composite PDA@BTO/CA demonstrates remarkable durability over 15,000 cycles and effectively detects a range of human motions (such as fist clenching, wrist bending, elbow movement, walking, running and jumping), transducing them into stable, precise electrical signals. Intriguingly, the hybrid nanogenerator device exhibits robust performance in extreme conditions, including underwater and high or low temperatures, while maintaining its good biodegradability. This work paves the way for advanced self-powered wearable biosensor devices capable of precise and reliable human motion monitoring.