Cotton Fabric‐Based Triboelectric Nanogenerator Enabled by Polydopamine Functionalization

Textile‐based triboelectric nanogenerators (TENGs) have garnered significant attention for creating wearable, self‐powered sensors for next‐generation smart fabrics that can convert mechanical energy into electricity. However, challenges, such as low power density, limit their application. Using synthetic fabrics or hybridizing with various nanomaterials can enhance performance, but these approaches increase the carbon footprint and pose risks of nanomaterial leaching. Recently, polydopamine (PDA)‐based TENGs have shown promise but involve multicomponent designs. Therefore, in this work, we utilized PDA to modify plain‐woven cotton textile for TENG development, without incorporating any additional component. Incorporating PDA yielded a voltage of 220 ± 4.1 V, a power density of 8.08 W/m 2 , a short‐circuit current of 32.5 µA, and a charge of 23.7 nC. The optimized material demonstrated stability for 90,000 cycles. A remarkable 150% increase in power density was obtained by tuning the dielectric properties of the optimized composition. The best‐performing sample exhibited pressure‐sensing sensitivity of 0.187 V/kPa. The optimized textile retained appreciable output after the initial washing cycles, but performance decreased significantly after the fifth cycle, suggesting limited washing tolerance. Finally, it was used for tactile sensing in single‐electrode mode. These findings open new pathways for developing polymer‐coated, sustainable fabrics that enhance human–computer interface technologies.