FeMn‐MOF@Bamboo Carbon Synergy: Lightweight Composites for Versatile and High‐Efficiency Electromagnetic Protection

With the rapid advancement of fifth‐generation communication technology and the widespread adoption of modern electronic devices, the development of lightweight and efficient multifunctional electromagnetic interference (EMI) shielding materials has become essential for addressing increasingly complex electromagnetic (EM) environments. In this study, natural bamboo sheets were used as a skeleton, and ultrathin lightweight FeMn@C/BC composite materials were successfully fabricated through the in situ growth of iron–manganese Prussian blue analogue (FeMn PBA) on their surfaces, followed by hot‐pressing and carbonization treatments. Owing to the abundant EM coupling network and unique hierarchical porous structure provided by the bamboo‐derived carbon skeleton and magnetic FeMn carbon nanocages. The developed composite demonstrates exceptional performance in shielding electromagnetic interference within the X‐band frequency range, attaining a shielding effectiveness value of 46.3 dB with an extremely small thickness of 0.18 mm, with an excellent normalized specific shielding effectiveness (SSE/t) of 9166.7 dB·cm 2 ·g −1 . In addition, the material possesses excellent electrothermal conversion performance; with an applied voltage of just 1 V, the device sustains a constant surface temperature of 65.4°C. These results highlight the potential of the FeMn@C/BC composite material for a wide range of applications, including architectural decoration and indoor heating systems.