MOFs-derived nanoscale dual-phase molybdenum carbides for enhanced electromagnetic wave absorption with integrated corrosion resistance

Nanoscale dual-phase molybdenum carbides possess a rich heterogeneous interface structure while maintaining the excellent electrical conductivity and corrosion resistance inherent to their single-phase counterparts. Investigating the electromagnetic wave absorption (EWA) characteristics of this dual-phase structure is crucial for optimizing the performance of molybdenum carbide-based absorbers. However, synthesizing nanoscale dual-phase molybdenum carbide remains challenging. This study employs a metal-organic framework (MOF) derivation strategy to synthesize nanoscale dual-phase Mo₂C/MoC materials. By varying the molybdate content introduced into the MOF precursor, distinct phases: MoC, MoC/Mo₂C, and Mo₂C were successfully obtained. The intrinsic relationship between their EWA performance and phase structure has also been systematically explored to elucidate the absorption mechanism in nanoscale dual-phase transition metal carbides. The optimized MoC/Mo₂C composite achieves a remarkable minimum reflection loss of −49.41 dB and an effective absorption bandwidth of 8.77 GHz at a thickness of just 1.52 mm, demonstrating exceptional EWA performance. This superior EWA performance is attributed to enhanced interfacial polarization and dipole polarization arising from the abundant heterogeneous interfaces within the dual-phase material. Furthermore, the dual-phase molybdenum carbide exhibits excellent corrosion resistance. This work facilitates the development of novel multifunctional molybdenum carbide-based EWA materials.