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arXiv · 2303.14909

Dramatically Accelerated Formation of Graphite Intercalation Compounds Catalyzed by Sodium

Akira Iyo·Hiraku Ogino·Shigeyuki Ishida·Hiroshi Eisaki
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Abstract

Graphite intercalation compounds (GICs) have a variety of functions due to their rich material variations, and thus,innovative methods for their synthesis are desired for practical applications. We have discovered that Na has a catalytic property that dramatically accelerates the formation of GICs. We demonstrate that LiC6n (n = 1, 2), KC8, KC12n (n = 2, 3, 4), and NaCx are synthesized simply by mixing alkali metals and graphite powder with Na at room temperature (~25 {\deg}C), and AEC6 (AE = Ca, Sr, Ba) are synthesized by heating Na-added reagents at 250 {\deg}C only for a few hours. The NaCx, formed by the mixing of C and Na, is understood to act as a reaction intermediate for a catalyst, thereby accelerating the formation of GICs by lowering the activation energy of intercalation. The Na-catalyzed method, which enables the rapid and mass synthesis of homogeneous GIC samples in a significantly simpler manner than conventional methods, is anticipated to stimulate research and development for GIC applications.

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Akira Iyo, Hiraku Ogino, Shigeyuki Ishida, Hiroshi Eisaki. 2023-03-27. Dramatically Accelerated Formation of Graphite Intercalation Compounds Catalyzed by Sodium. https://doi.org/10.1002/adma.202209964

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