Defect engineering boosts microwave absorption in TaxNb1-xC nanowires

The solid solution formed by the combination of multiple cations has been extensively investigated due to its distinctive lattice distortion effect, which imparts unique electromagnetic properties. In particular, the regulation of dielectric and magnetic properties can be achieved through element selection. Herein, the stability of Ta_xNb_1-xC was predicted through geometric optimization of crystal structure, and Ta_xNb_1-xC nanowires were successfully synthesized through F-ion-assisted carbothermal reduction method. The introduction of bimetallic ions forms significant carbon defects and lattice distortion, which undoubtedly induces the formation of strong interface polarization and defect polarization, resulting in high dielectric loss. Furthermore, the significant presence of imperfections leads to a decrease in both the dielectric constant and conductivity, thereby achieving impedance balance. The design of a one-dimensional structure also facilitates the formation of conductive pathways, promoting carrier transitions. Benefiting from a variety of loss mechanisms and appropriate impedance matching, solid solution Ta_xNb_1-xC shows excellent electromagnetic wave absorption (EWA) performance. This research presents a promising strategy for developing single-phase materials with excellent EWA performance.

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