Ni/Ni3ZnC0.7 modified alginate-derived carbon composites with porous structures for electromagnetic wave absorption

Electromagnetic wave (EMW) absorption materials with both high-performance and low-cost are demanded to reduce unwanted noise at microwave communication frequencies. Herein, Ni/Ni3ZnC0.7 modified alginate -derived carbon (Ni/Ni3ZnC0.7/C) composites were successfully prepared by constructing a Ni2+-Zn2+-alginate gel, followed by freeze-drying and carbonization processes. The co-introduction of nickel and zinc greatly improved EMW absorption properties. By adjusting the amounts of Ni2+ and Zn2+ ions, Ni/Ni3ZnC0.7/C composites with excellent impedance matching and EMW absorption performance were realized, evidenced by a maximum reflection loss of-40.2 dB (14.8 GHz, 2.0 mm) and an effective absorption bandwidth of 5.4 GHz (12.6-18.0 GHz, 2.0 mm). This work provides a very simple and green strategy for designing lightweight and high-performance EMW absorbers offering considerable potential for practical applications.

Automated summary

Ni/Ni3ZnC0.7 modified alginate-derived carbon composites were successfully prepared by constructing a Ni2+-Zn2+-alginate gel, followed by freeze-drying and carbonization processes, showing improved EMW absorption properties with a maximum reflection loss of -40.2 dB and an effective absorption bandwidth of 5.4 GHz.