Controlling intermolecular explosion in the synthesis of compacted multi-graphene structures

The demand for synthesized carbon-based materials like compacted multi-graphene structures (CMGSs) is increasing in electronics, energy, and aerospace due to their high thermal conductivity. Researchers expect that they will replace conventional metal-based materials in thermal management, but their implementations remain impractical due to high production costs.

To overcome this issue, Shulyak et al. designed controlled, cost-efficient CMGS engineering approaches, yielding products that are more lightweight and thermally conductive than silver and copper.

The authors filled the interlayer space of graphite with intercalate substances, which, upon rapid heating, evaporate and generate pressure within the structure in a process called intermolecular explosion. By controlling intermolecular explosion, they found that various complex CMGS morphologies can be achieved.

In particular, the team explored standard and novel “soft” synthesis approaches, the latter being composed of five alternating stacks of graphene layers instead of three, and treated with gentler intercalation regimes. The result of “soft” synthesis is a material with thermal conductivity reaching approximately 500 W/(m·K) and low density, outperforming copper in both aspects.

Subsequent material analyses showed how micro- and meso-structural alterations influenced the final conductivity of CMGSs.

“We aimed to clarify the mechanisms by which these factors affect conductivity, providing a practical framework for refining existing mathematical models and guiding the design of advanced compacted multi-graphene materials,” said author Nikolai Morozov.

The authors plan to further optimize the performance of thermal conductors by deeply investigating conductivity mechanisms.

“Future research efforts will focus on achieving ultra low-porosity compacted multi-graphene structures with thermal conductivity values exceeding 700 W/(m·K),” said Morozov. “In parallel, we plan to investigate the composite structures “multigraphene-metal” to better understand interfacial heat transfer mechanisms across phase boundaries.”

Source: “Effect of intermolecular explosion on thermal conductivity in multi-graphene structures,” by V. A. Shulyak, N. S. Morozov, R. A. Minushkin, K. E. Klyukova, V. Yu. Gubin, A. V. Gracheva, S. N. Chebotarev, and V. V. Avdeev, Applied Physics Letters (2025). The article can be accessed at https://doi.org/10.1063/5.0269483 .