Large area fabrication of graphene based fabrics for multifunctional e-textiles in energy harvesting and chemical warfare agent sensing applications.

Y. Jin, D. Ka, H. Jung, D. Heo, S. Lee
Agency for Defense Development,
Korea

Keywords: graphene, reduced graphene oxide, e-textile, chemical warfare agent, energy harvesting

Summary:

The wearables with multifunctionality have gained special attention due to their great possibility for enery harvesting, healthcare, fitness and sensing. Recently e-textiles are considered to be promising in the military applications especially for intelligent personal uniforms or integrated individual combat systems. Graphene-based fabrics are widely investigated for e-textiles because of their advantages over traditional metal based electrically conductive textiles[1-3]. However, graphene based e-texitles are not easily scalable yet and their practical applications are not clearly defined. In the work, we introduce a fast and easy fabrication of rGO based conductive fabrics in a large scale. Reduced graphene oxide can be easily coated on fabric with speed up to 100m/min in a padding-drying technique. Both graphene e-textiles and e-yarns can be fabricated and the electrcial conductivity increasd by several orders of magnitude for a few padding cylcles. The sheet resistance of grapehene e-textiles can be reached as low as 1 kΩ/sq. The impedance techniques was used to characterize the electrical properties of graphene e-textiles. The measured impedance data was analyzed by equivalent circuit elements to have better idea as to how the conductive channels and interfaces are formed. The data was fitted well by a Nested RL circuit in all four different dielectric functions (impedance; Z*, admittance; Y*, electric modulus; M*, and permittivity; ε*) And the graphene based e-textiles were integrated in triboelectrical energy harvestors to visualize the possibility of energy harvesting in military uniforms or individual combat systems. The graphene e-textiles were also integrated in sensing applications of toxic chemicals such as chemical warfare agents. It is believed that the facile fabrication and great properties of graphene based e-textile can find real applications in multifunctional textiles for energy harvesting, millitary suits and wearble sensors.