Hydrangea-like Ni/NiO/C composites derived from metal-organic frameworks with superior microwave absorption

The hydrangea-like Ni/NiO/C composites have been successfully synthesized by in-situ pyrolysis stemmed from Ni-MOFs. The composition and structure can be adjusted by controlling the pyrolysis temperature, and it leads to the graphitization degree and electromagnetic parameters. A broad effective absorption bandwidth of the composite up to 5.67 GHz with the maximum reflection loss of −47.72 dB in 1.9 mm thickness. The results demonstrate hydrangea-like Ni/NiO/C composites have superior microwave absorption resulted from the synergistic effect between the unique structure, dielectric loss, and magnetic loss. Therefore, this work confirmed that hydrangea-like structure composite can be an ideal candidate for highly efficient microwave absorption materials with a facile preparation process and flexible control of electromagnetic parameters.