Enhanced absorption properties of ordered mesoporous carbon/Co-doped ordered mesoporous carbon double-layer absorbers

Abstract

Ordered mesoporous carbon (OMC) and metal-doped (M-doped) OMC composites are prepared, and their electromagnetic (EM) parameters are measured. Using the measured EM parameters we calculate the EM wave absorption properties of a double-layer absorber, which is composed of OMC as an absorbing layer and M-doped OMC as the matching layer. The calculated results show that the EM wave absorption performance of OMC/OMC—Co (2.2 mm/2.1 mm) is improved remarkably. The obtained effective absorption bandwidth is up to 10.3 GHz and the minimum reflection loss reaches −47.6 dB at 14.3 GHz. The enhanced absorption property of OMC/OMC—Co can be attributed to the impedance match between the air and the absorber. Moreover, it can be found that for the absorber with a given matching layer, a larger value of Δtanδε(= tanδ69 absorbing − tanδε matching) can induce better absorption performance, indicating that the difference in impedance between the absorbing layer and the matching layer plays an important role in improving the absorption property of double-layer absorbers.