Multifunctional PDMS/Coal gasification fine slag composites for enhanced electromagnetic shielding and thermal management

Coal gasification fine slag (CGFS), a representative challenging solid waste in the coal chemical industry, has garnered significant attention due to its high carbon content and inorganic oxide components. Notably, the magnetic Fe3O4 particles are uniformly distributed within the CGFS matrix, rendering it a natural magneticdielectric composite material. Capitalizing on this unique characteristic, this study innovatively proposes the application of CGFS in the field of EMI shielding. Through a facile solution blending-hot pressing process, flexible PDMS/CGFS composites were fabricated. The results demonstrate that with a CGFS loading of 40 wt%, the composite achieves an average shielding effectiveness of 34.7 dB in the X-band, significantly surpassing the commercial standard of 20 dB. Simultaneously, the composite exhibits an absorption coefficient (A) of 0.35, effectively mitigating secondary radiation pollution. Additionally, the PDMS/CGFS composite also possesses multifunctional characteristics, including thermal conductivity, Joule heating, and photothermal conversion capabilities. Therefore, this study not only provides an innovative approach for the utilization of CGFS but also opens new research directions for developing novel multifunctional EMI shielding materials.