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arXiv · 1410.3938

Novel nanometer-level uniform amorphous carbon coating for boron powders by direct pyrolysis of coronene without solvent

ShuJun Ye·MingHui Song·Hiroaki Kumakura
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Abstract

A 3 nm coronene coating and a 4 nm amorphous carbon coating with uniform shell-core encapsulation structure for nanosized boron (B) powders are formed by a simple process, where coronene is directly mixing with boron particles without a solvent, and heated at 520 °C for 1 h or at 630 °C for 3 h in a vacuum-sealed silica tube. Coronene has a melting point lower than its decomposition temperature, which enables liquid coronene to cover B particles by liquid diffusion and penetration without the need for a solvent. The diffusion and penetration of coronene can extend to the boundaries of particles and inside agglomerated nanoparticles to form a complete shell-core encapsulated structure. As the temperature is increased, thermal decomposition of coronene on the B particles results in the formation of a uniform amorphous carbon coating layer. This novel and simple nanometer-level uniform amorphous carbon coating method is possibly applied to many other powders, thus it has potential applications in many fields with low cost.

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ShuJun Ye, MingHui Song, Hiroaki Kumakura. 2015-01-09. Novel nanometer-level uniform amorphous carbon coating for boron powders by direct pyrolysis of coronene without solvent. https://doi.org/10.1088/0957-4484%2F26%2F4%2F045602

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