Electroless silver nanoparticles functionalized CA-EDA/GO cotton fabric for flexible wearable antenna

Abstract

Flexible wearable antennas are widely useful for real-time data transmission in healthcare, smart textiles, and IoT applications etc. The flexible antenna needs excellent bonding strength, mechanical flexibility, and high electrical conductivity

these properties can be tailored by functionalization of the cotton fabric. Herein, the cotton fabrics are first functionalized with citric acid (CA), also with ethylene diamine and graphene oxide (EDA/GO), followed by electroless coating of the silver nanoparticles. The ethylene diamine and graphene oxide solution (EDA/GO) enhances the adhesion and mechanical flexibility of the deposited silver nanoparticles. Structural analysis indicates that CA, EDA, and GO treatments induce hydrogen bonding, covalent ester linkages (–O–C(= O)–), C–N bonds associated with amine functionalities, and ionic interactions. The structural results further confirm the presence and effective embedment of silver nanoparticles between the graphene nanosheets, leading to uniform and enhanced surface coverage. The silver-coated fabrics maintain sheet resistance and flexural rigidity values of 0.25 Ω/□ & 0.160 gf-cm for CA-Ag coated fabric and 0.47 Ω/□ & 0.118 gf-cm. The modified fabric remains stable after multiple washings (> 20 washing cycles), indicating very good washing durability and high bending stability. The silver coated fabrics antennas have shown the lowest return loss (S11) below − 40 dB and EDA/rGO–CA–Ag antenna records the maximum bandwidth of greater than 2 GHz. The EDA/rGO–CA–Ag-based antenna exhibited lower side-lobe and back-radiation levels than the CA–Ag-based antenna, suggesting reduced unwanted radiation. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2026.