Hierarchical FeCoNiOx-PDA-rGO/WPU layers constructed on the polyimide fabric by screen printing with high microwave absorption performance

The fabrication of flexible microwave absorbers with high-performance has become an arduous challenge for applications of anti-electromagnetic pollution and radar stealth technology. Herein, a series of FeCoNiOx-PDA-rGO absorbers were prepared and coated on the surface of pretreated polyimide (PI) fabric with PDA-rGO, and finally by screen printing FeCoNiOx-PDA-rGO/WPU for acquiring robust microwave absorption performance, in which the first layer of treated PI fabric was used as the microwave-reflection layer, the medium microwave absorbing powder and water-based polyurethane (WPU) hybrid coating served as the microwave-absorbing layer, and the outside hydrophobic polydimethylsiloxane (PDMS) layer was utilized as the microwave-transmission layer. The well-designed microwave absorption fabric exhibits excellent performance in the X-band (8.2–12.4 GHz). The minimum reflection loss (RL min ) value of the designed fabric can reach −74.70 dB with a thickness of 3.97 mm. Meantime, almost in the entire X-band, the sample can absorb more than 99% (RL < -20 dB) of incident electromagnetic waves. Besides, the performance can be adjusted by changing the load rate of each microwave absorbing layer to obtain lighter and thinner samples in practical applications. We believe this work will bring new inspiration to the design of flexible and wearable microwave absorbers.