Superhydrophobic wave-absorbing cotton fabric based on peanut shell porous carbon

The increasing demand for electronic products has exacerbated the phenomenon of electromagnetic pollution, which in turn has driven the development of high-performance flexible microwave absorbing materials. In this work, cotton fabrics were first modified with polydopamine (PDA). Afterwards, the polydimethylsiloxane (PDMS) and porous peanut shell carbon material (KPS) were applied to the modified cotton fabric. The prepared fabric showed superhydrophobicity with a water droplet contact angle of 163.7°. The optimized fabric exhibited excellent wave-absorbing performance due to the synergistic effect of conduction loss, interfacial polarization loss and surface roughness topography. At a matching thickness of 2.5 mm, the minimum reflection loss value reached 47.13 dB, and the effective bandwidth covered almost the entire X-band. PDA/KPS/PDMS-Cotton had excellent UV resistance. Its UPF value is 1317.31, and the transmittance of UVA and UVB was 0.11% and 0.06%, respectively. In addition, the obtained cotton fabric was robust enough to withstand damage such as repeated rubbing and still maintained superhydrophobicity and microwave absorption properties. This study provided a promising and effective way to develop durable and flexible materials with microwave absorption properties.