Morphology-controlled CoNi/C hybrids with bifunctions of efficient anti-corrosion and microwave absorption

Till now, fewer literatures have investigated the corrosion resistance of microwave absorbers, especially mental@C/carbon matrix derived from MOF composites, although it is known that carbon shells possess a protective effect. Herein, three kinds of morphology-controlled CoNi/C-N doped architectures were successfully fabricated via a sequence of processing, namely coprecipitation for ZIF-67, subsequent Ni2+ exchange and ultimate carbonization. Apart from composition characterization, the effects of microstructure tailoring and temperature controlling on electromagnetic response as well as attenuation performance were revealed, where dodecahedron-shaped composites possessed the highest permittivity. By contrast, rod-shaped composites (CoNi/C-r-550 and CoNi/C-r-700) were endowed with superior comprehensive absorption properties, e.g., RLmin: -49.8 dB and -64.0 dB; EAB: 5.7 GHz and 4.8 GHz, respectively. Besides, samples CoNi/C-d-700 and CoNi/C-r-700 present higher corrosion potential (E-corr) and lower corrosion current (I-corr). Hence, these corrosion-resistant microwave absorbers with outstanding absorption stability, wetting effect as well as environmental adaptability, can be used as a candidate/raw material for intelligent devices. (C) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.