Flexible protective cotton fabrics based on multi-layer nano coating: Sustaining electromagnetic interference shielding capabilities in fire conditions

Abstract

Coated electromagnetic interference (EMI) shielding textiles with conductive coatings could efficiently reflect and absorb electromagnetic waves (EMWs), and are widely used in various applications, including consumer electronics, medical technology, and the automotive industry. However, the accumulation of heat during operation may pose a fire risk, potentially damaging the coating and compromising its ability to provide effective electromagnetic protection under fire conditions. To address this issue, we designed a multi-layer nano coating incorporating flame retardants and conductive nanofillers, specifically AgNWs, MXene, and graphene. This coating could achieve sustainable EMI shielding capabilities under fire conditions. Especially, the A1-M1.5-G0.5 exhibited excellent flame retardancy, reducing the total heat release (THR) value from 3.9 ± 0.2 MJ·m⁻² to 1.9 ± 0.1 MJ·m⁻², and the peak heat release rate (pHRR) value was 89 % lower than that of cotton fabric. Its initial EMI SE_T reached 77.5 ± 2.4 dB, and even after 10 min of continuous flame exposure, the woven structure and conductive network remained intact, still providing 99.9 % shielding of EMWs. This flame-retardant coated EMI shielding fabric prevents the shielding performance failure of existing textiles due to combustion and maintains protection even in fire conditions, which carries significant practical value.