Sustainable assembling of graphite flakes into graphite/carbon composite foams with thermal percolative interfaces for active heat dissipation

Current methods for producing open-pore graphite foams with heat dissipation potential involve costly graphitization processes, limiting their widespread use. This study presents a sustainable approach to fabricate high-performance graphite/carbon composite foams with porosities in the range of 49–82 %. The method involves the densification and carbonization of solid mixtures comprising natural graphite flakes, sucrose, and NaCl particles. The dissolution of NaCl creates coarse pores, while carbonized sucrose contributes fine porosity and serves as a binder to impart mechanical stability, ensuring the maintenance of thermally conductive percolative contacts between flakes. The composite foams exhibit thermal conductivities of up to 91 Wm−1K−1, permeability values in the range of 10−11–10−10 m2, and excellent mechanical properties. Experimental and computational findings demonstrate that the developed materials surpass the heat dissipation capabilities of conventional heat sinks based on graphite and aluminum foams by about 3 and 1.5 times, respectively, making them excellent candidates for thermal management applications.