Biomass-derived carbon materials for effective broadband electromagnetic conversion

Biomass materials are advantageous as carbon resources for various applications including electromagnetic (EM) conversion due to their abundance and renewability. To select the most appropriate biomass, various factors should be considered while there is a lack of comparisons in-between. Here, six types of biomass precursors have been investigated with features including carbon disorder, conductivity, composition complexity, functional group and specific surface area compared. It has been found that enriched composition complexity, functional groups and carbon disorder are critical to enhance the polarization and loss capability, which has no effect on impedance matching, giving rise to optimum reflection loss of - 38.9 dB and a wide effective bandwidth of 5.3 GHz at the thickness of 2.8 mm. As such the work not only shed light on high-performance biomass-derived EM wave absorbers, but also provides important references for the selection of biomass materials for various fields such as sensing, energy and catalysis. [GRAPHICS] .