Tailoring the type and size of Fe-catalytically synthesized nanodiamond during chlorine-etching carbide at ambient pressure: Influence of the type of carbide as precursor

摘要

How to synthesize nanodiamonds (NDs) under moderate conditions is still a challenging issue. Recently, we have demonstrated that high-stress embedding the Fe catalyst into VC can lead to the catalytic synthesis of NDs by chlorine-etching VC at atmospheric pressure. Herein, we have further probed into the influence of the carbide type on the Fe-catalytic synthesis of NDs, where four carbides - VC, TiC, NbC and beta-SiC are used as the precursor to be chlorine-etched in the presence of Fe catalyst, respectively. It has been discovered that various types of NDs, including C type, H type and R type, can be catalytically synthesized. The type of carbide has a decisive influence on the Fe-catalytic synthesis of NDs. Furthermore, the size and type of NDs synthesized are closely related to the number of carbon atoms contained per unit volume in the carbide. This finding may open a new avenue for tailoring the size and type of NDs to satisfy the specified application requirement.