Polarization regulation in core-shell HNTs@Metal/C for high-performance of electromagnetic wave absorption

Enhancing polarization loss is an effective method to improve electromagnetic wave absorption (EMA) performance. However, constructing more interfaces and inducing defects is a significant challenge in polarization regulation. This paper reports synthesizing a core-shell structure HNTs@M/C (M=Cu, Co, Zn) by pyrolysis of metal-organic frameworks (MOFs). The enhancement of conduction loss is attributed to the electronic conduction network formed by the carbon layer and the metal particles. Co nanoparticles (NPs) create more interfaces with the carbon layer, significantly boosting polarization performance. Additionally, Zn sublimation induces numerous defects in the carbon layer, leading to cumulative amplification of polarization and stronger dielectric resonances in HNTs@Zn/C. With a thickness of 2.4 mm, the HNTs@Zn/C achieve an effective absorption bandwidth (EAB) of 6.9 GHz, covering the entire Ku-band with a minimum reflection loss of −61 dB. This work provides design strategies for interfacial and point interaction of polarization regulation. •This work synthesized HNTs@Metal/C with a core-shell structure.•HNTs@Metal/C composites were used in electromagnetic wave absorption for the first time.•HNTs@Metal/C derivatives exhibit outstanding electromagnetic waveabsorption performance.•A mechanism for regulating the polarization properties by replacing the ligand metal is elucidated.