Direct fabrication of few-layer graphene via molten salt-assisted magnesiothermic reduction

Abstract

Graphene materials like turbostratic graphene exhibit remarkable promise for an array of applications, spanning from electronic devices to aerospace technologies. It is essential to develop a fabrication method that is not only economical and efficient, but also environmentally sustainable. In this study, the molten salt-assisted magnesiothermic reduction (MSAMR) method is proposed for the synthesis of few-layer turbostratic graphene. K₂CO₃ serves as both the carbon source and the catalyst for graphitization, facilitating the formation of the graphene structure, while in-situ generated MgO nanoparticles exert confinement and templating effects on the growth of graphene. The molten salts used effectively prevent the aggregation and the Bernal stacking of graphene sheets, ensuring the few-layer and turbostratic structure. The synergistic effects of K₂CO₃, in-situ generated MgO, and molten salts guarantee the formation of few-layer turbostratic graphene at a relatively low temperature, characterized with 4–8 stacking layers, a mesopore-dominated microstructure, and a high degree of graphitization.

Graphical abstract

Keywords

few-layer turbostratic graphene / magnesiothermic reduction / molten salt / potassium carbonate / graphitization / mesopore-dominated microstructure

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Declaration of competing interests

The authors declare no conflict of interests.

Acknowledgements

We would like to acknowledge the funding support from the National Natural Science Foundation of China (Grant No. 22278404).

Online appendix

Electronic supplementary material (ESM) can be found in the online version at https://doi.org/10.1007/s11706-025-0722-3 and https://journal.hep.com.cn/foms/EN/10.1007/s11706-025-0722-3 that includes Figs. S1–S5 and Table S1‒S3.

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