Characterization of boron carbide nanoparticles prepared by a solid state thermal reaction

The production of boron carbide (B4C) nanoparticles was investigated in a conventional high temperature furnace reactor. The reaction was carried out by heating a mixture of amorphous carbon and amorphous boron at 1550 °C to efficiently obtain a quantity of B4C. Scanning electron microscopy studies showed the average size of B4C particles was 200 nm, ranging from 50 nm to 350 nm. X-ray diffraction transmission electron microscopy and electron diffraction studies indicated that the prepared nanoparticles were crystalline B4C with a high density twin structure. High resolution transmission electron microscopy and selected area diffraction were also used to further characterize the structure of the prepared B4C particles, while energy dispersive spectroscopy and electron energy loss spectroscopy were used to determine the stoichiometry of the product. A solid state diffusion reaction mechanism is proposed.