Sodium alginate aerogel derived SiC@Co-C 3D network enhances electromagnetic wave absorption and thermal conductivity of PDMS based composite

Interface packaging materials with both electromagnetic wave absorption and high thermal conductivity remains a research hotspot in modern electronics industry and aerospace field. In this paper, the cobalt alginate aerogel derived from biomass sodium alginate was carbothermal reduced to obtain a three-dimensional skeleton structure composed of zero-dimensional Co metal particles, one-dimensional silicon carbide (SiC) whiskers and biomass derived carbon (C). The dielectric-electromagnetic effect of the filler network makes the obtained polydimethylsiloxane (PDMS) based composite (PDMS/SiC@Co-C) exhibits good electromagnetic wave absorption performance, with the lowest reflection loss (RL_min) value can reach −40.08 dB, and the effective absorption bandwidth (EAB_max) can reach 4.16 GHz at the thickness of 1.9 mm. The unique three-dimensional overlapping structure makes the thermal conductivity of PDMS/SiC@Co-C increase to 1.856 W/m·K, which is 1345 % higher than that of PDMS. This work provides an important reference value for the development of interface packaging materials used in microelectronics and aerospace fields.