Ultra-thin robust CNT@GC film integrating effective electromagnetic shielding and flexible Joule heating

The demand for lightweight, thin electromagnetic interference (EMI) shielding film materials with high shielding effectiveness (SE), excellent mechanical properties, and stability in complex environments is particularly pronounced in the realm of flexible and portable electronic products. Here, we developed an ultra-thin film (CNT@GC) in which the glassy carbon (GC) layer wrapped around and welded carbon nanotubes (CNTs) to form a core–shell network structure, leading to exceptional tensile strength (327.2 MPa) and electrical conductivity (2.87 × 10⁵ S·m⁻¹). The CNT@GC film achieved EMI SE of 60 dB at a thickness of 2 μm after post-acid treatment and high specific SE of 3.49 × 10⁵ dB·cm²·g⁻¹, with comprehensive properties surpassing those of the majority of previous shielding materials. Additionally, the CNT@GC film exhibited Joule heating capability, reaching a surface temperature of 135 °C at 3 V with a fast thermal response of about 0.5 s, enabling anti-icing/de-icing functionality. This work presented a methodology for constructing a robust CNT@GC film with high EMI shielding performance and exceptional Joule heating capability, demonstrating immense potential in wearable devices, defense, and aerospace applications.