A core-shell Cu₂O@Cu-MOF for electromagnetic wave absorption and selective shielding.

Area of Science:

• Materials Science
• Nanotechnology
• Electromagnetics

Background:

• Growing adoption of wireless technologies necessitates advanced electromagnetic (EM) protection materials.
• Existing materials often lack frequency-specific performance and efficient energy harvesting capabilities.

Purpose of the Study:

• To develop a novel core-shell material for high-performance EM protection.
• To investigate the frequency-dependent electromagnetic characteristics of the new material.
• To explore applications in EM wave absorption, frequency-selective shielding, and energy harvesting.

Main Methods:

• Synthesized core-shell Cu2O@Cu-HHTP using cuprous oxide cubes coated with copper hexahydroxytriphenylene (Cu-HHTP).
• Characterized the material's frequency-dependent electromagnetic properties, including dielectric loss tangent and attenuation constant.
• Evaluated EM wave absorption (reflection loss) and shielding effectiveness (shielding effectiveness and transmission coefficient differences).

Main Results:

• Cu2O@Cu-HHTP exhibited peak dielectric loss tangent and attenuation constant at 15.6 GHz.
• Achieved minimum reflection loss of -33.4 dB with thickness-independent absorption in the 13.6-17.0 GHz range.
• Demonstrated significant EM shielding with a shielding effectiveness difference of 19.8 dB and transmission coefficient difference of 0.93.

Conclusions:

• The developed Cu2O@Cu-HHTP material shows excellent frequency-selective EM wave absorption and shielding capabilities.
• The material's superior EM attenuation facilitated the development of an EM energy conversion device for waste energy harvesting.
• This study expands the utility of conductive MOFs in EM protection and advances high-performance, frequency-selective materials.