Fabrication of flexible flower-like ZIF-7-derived N-doped carbon composite films for high-efficiency electromagnetic wave absorption

The rapid development of modern communication technology has exacerbated electromagnetic pollution, creating a strong demand for high-performance electromagnetic wave (EMW) absorption materials. Metal-organic frameworks (MOFs) derivatives are promising candidates owing to their tunable structures and high specific surface areas. However, conventional MOFs-based absorbers still suffer from magnetic component aggregation or insufficient dielectric loss, leading to poor impedance matching and narrow effective absorption bandwidth (EAB). Herein, flexible flower-like non-magnetic ZIF-7-derived nitrogen-doped carbon films were fabricated via electrospinning and controlled carbonization. By regulating carbonization temperature and precursor concentration, the morphology and electromagnetic parameters were optimized. The synergistic effect of the unique flower-like structure and nitrogen doping enhances dielectric loss and optimizes impedance matching. Consequently, ZIF-7-NCF-2 achieves a minimum reflection loss (RL) of −75.50 dB at 2.57 mm and an ultra-broad EAB of 11.36 GHz at 3.35 mm, covering almost the entire X and Ku bands. This work provides a feasible strategy for designing high-performance and broadband non-magnetic MOFs-derived EMW absorption materials.