Molten salt synthesis of titanium carbide using different carbon sources as templates

Abstract

In this work, different carbon sources, such as nano-sized carbon black (CB), carbon nanotubes (CNT), carbon fibers (CF) and graphene (GR), were reacted with titanium micro-powders, to synthesise titanium carbide (TiC) in the mixed molten salts of LiCl–KCl–KF at 1100 °C for 6 h. There experiments were performed to investigate the accuracy of “carbon-template-growth” mechanism for the formation of TiC, that was proposed previously using micro-sized titanium and submicro-sized CB powders. The products synthesised from the different carbon sources were observed and characterised by scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. The results showed that the visual morphologies of the TiC products mainly retained the shapes of the as-received carbon sources, that is, they presented an equiaxed-shape with a grain size of 10–20 nm from CB, a shell layer along the outer surface of the CNTs and CF, and a flake-shape with the GR. These morphologies reveal that the formation of TiC is indeed controlled by the “carbon-template-growth” mechanism.