Enhanced Microwave Absorption Performance of α-FeOOH Nanorods on Carbon Aerogel Powder

High-performance microwave absorbers are mainly based on reasonable microstructural designs and composition regulation. Herein, a broadband microwave absorber was obtained by a two-step hydrothermal method. Notably, the transformation of MnO2 nanosheets to α-FeOOH nanorods was successfully realized on carbon aerogel powder, and the microwave absorption effect of the absorber can be adjusted in three-band absorption (S, X, and Ku bands) by changing the thickness of the absorber. The results show that the minimum reflection loss (RLmin) of the α-FeOOH/CA composite is −38 dB at a frequency of 13.28 GHz, and the corresponding effective absorption bandwidth of less than −10 dB could completely cover the Ku band. This study provides a new idea for designing carbon aerogel powder microwave absorbers reasonably and for adjusting impedance effectively.