Interface-Engineered Rod-like Fe ₂ O ₃ (Co ₃ O ₄ )/Carbon-Nanotube Composites for Efficient Microwave Absorption

The development of advanced wave-absorbing materials integrating low reflection loss, broad absorption bandwidth, and lightweight characteristics has emerged as a key research focus in addressing electromagnetic pollution. In this study, we successfully fabricated rod-like Fe 2 O 3 (Co 3 O 4 )/Carbon-nanotube (CNT) composites through an eco-friendly hydrothermal route, followed by controlled heat treatment. By precisely tuning the CNT loading, a synergistic effect is realized via enhanced dipole/interface polarization, optimized impedance matching, and a well-developed magnetic coupling network. The resulting composite exhibits exceptional microwave absorption performance, achieving a minimum reflection loss of −53.5 dB at a thickness of 2.5 mm. The unique nanorod architecture provides a large specific surface area and abundant heterogeneous interfaces while simultaneously promoting polarization loss and multiple scattering, thereby significantly enhancing the electromagnetic energy dissipation. This work highlights the importance of morphological design in boosting absorption performance and demonstrates a green synthesis strategy for high-performance microwave absorbers.