A Multi-Scale Cross-Band Defense System Integrating Decoupled Visible, Dynamic Infrared Camouflage and Electromagnetic Shielding.

Cross-band camouflage technology is a critical necessity, enabling personnel and equipment to evade detection across evolving surveillance systems, thereby enhancing survivability and mission success. Herein, this work develops a layer-structured composite system based on carbon nanotube (CNT) film comprising ionic liquid (IL) interlayer for infrared (IR) modulation and surface-engineered Cu2O nanoparticles for visible camouflage. The CNT/IL/CNT architecture enables reversible IR emissivity switching (Δε≈0.55) through electrically driven ion intercalation/deintercalation within 2 s, while spray-coated Cu2O nanoparticles (100 ~ 400 nm diameter) on the top CNT film layer generate rich structure colors with 90% IR transmittance. This spectral-decoupling design overcomes the traditional trade-off between color visibility and IR transmittance observed in pigment-based systems. Remarkably, due to physical interface coupling, the Cu2O-coated layer-structured system maintains exceptional electrical conductivity, enabling simultaneous electromagnetic interference shielding and electrothermal energy conversion. The integrated system demonstrates long-term operational stability. By unifying visible-IR camouflage, electromagnetic protection, and energy management in a lightweight platform, this work provides an important paradigm for cross-band camouflage technologies .