LOW TEMPERATURE SYNTHESIS OF BaB6 NANOMETER POWDERS

The reaction synthesis of barium boride (BaB6) nanoparticles under low temperature was investigated in this study. X-ray diffraction (XRD) was used to investigate the phase and the structure of BaB6. The characterization for microstructure was performed by Field Emission Scanning Electron Microscope (FESEM) with EDS, TEM, Fourier transform infrared (FTIR) spectroscopy and Raman scattering spectroscopy. It is concluded that BaB6 nanoparticles can be successfully prepared under low temperature at 500°C. XRD pattern shows that the nanoparticles are consisted of predominantly (110)-oriented BaB6 phase. The powders are polygonal-like shape with the average size of 200 nanometers. TEM identified that each nanoparticle shows perfect single crystal and cubic structure. The boron-to-barium atomic ratio of 5.24:1 was determined, less than the stoichiometric ratio of 6:1. BaB6 nanoparticles can absorb infrared spectrum at 459, 690, 993, 1329, 1619, 2449 and 3423cm-1 in the test range of 400~4000cm-1, respectively. Three peaks at 677.1, 823.5 and 1116.4cm-1 can be observed clearly from the Raman spectra of BaB6 nanoparticles at room temperature. The results showed that the electron dispersion of B6 octahedron in BaB6 is two-dimensional pancake-type without lattice distortion, which may account for the unique physical properties of BaB6 nanoparticles.