Flexible and waterproof nitrogen-doped carbon nanotube arrays on cotton-derived carbon fiber for electromagnetic wave absorption and electric-thermal conversion

It is highly desirable, but challenging to develop multi-functional electromagnetic wave (EMW) absorbing material for practical applications in some special environments. Herein, we successfully fabricated cobaltnanoparticle-embedded N-doped carbon nanotube arrays on the carbonized cotton fiber cloth as multifunctional material with an excellent EMW absorption, flexibility, hydrophobicity, and electric-thermal performance. The excellent multifunction benefits from high conductivity, large specific surface area, abundant N dopants, and three-dimensional open porous features. Minimal reflection loss and efficient absorption bandwidth of the optimized material as EMW absorbers can reach 57.8 dB and 4.5 GHz, respectively, which are better than most reported carbon-based absorbers. Meanwhile, theoretical simulations of the radar cross-sectional (RCS) further confirm that the multifunctional material has excellent EMW attenuation performance and potential in practical application. Moreover, the materials possess strong hydrophobicity and high electrical conductivity, endowing them with other attractive functions of self-cleaning and good electric thermal performance, which expand the potential applications range of EMW absorption materials. Our present method can be extended to design next generation EMW absorbing materials with multifunctionalities for practical applications in harsh environments.

Automated summary

In this study, a multifunctional electromagnetic wave absorbing material was successfully developed, which exhibited excellent electromagnetic wave absorption performance surpassing most carbon-based absorbers. The material also possessed flexibility, hydrophobicity, and electric-thermal performance. The outstanding performance was attributed to its high conductivity, large specific surface area, abundant dopants, and unique structure. Additionally, the material showed self-cleaning and good electric-thermal properties. The research method used in this study can be applied to design next-generation multifunctional electromagnetic wave absorbing materials for harsh environments.