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DOE OSTI · 1777725

Ambient Temperature Graphitization Based on Mechanochemical Synthesis

Yuan, Yating·Wang, Tao·Chen, Hao·Mahurin, Shannon Mark·Luo, Huimin·Veith, Gabriel·Yang, Zhenzhen·Dai, Sheng
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Abstract

Graphite has become a critical material because of its high supply risk and essential applications in energy industries. Its present synthesis still relies on an energy-intensive thermal treatment pathway (Acheson process) at about 3000 °C. Herein, a mechanochemical approach is demonstrated to afford highly crystalline graphite nanosheets at ambient temperature. The key to the success of our methodology lies in the successive decomposition and rearrangement of a carbon nitride framework driven by a denitriding reaction in the presence of magnesium. The afforded graphite features high crystallinity, a high degree of graphitization, a thin nanosheet architecture, and a small flake size, which endow it with superior efficiency in lithium-ion batteries as an anode material in terms of rate capacity and cycle stability. Finally, the mild and cost-effective pathway used in this study could be a promising alternative for graphite production.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYcarbon nitridegraphitelithium-ion batteriesmagnesiummechanochemistry

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Yuan, Yating, Wang, Tao, Chen, Hao, Mahurin, Shannon Mark, Luo, Huimin, Veith, Gabriel, Yang, Zhenzhen, Dai, Sheng. 2020-08-27. Ambient Temperature Graphitization Based on Mechanochemical Synthesis. https://doi.org/10.1002/anie.202009180

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