Abstract: Calcium hexaboride (CaB6) nanopowder was prepared by low temperature chemical reaction of CaCl2 and NaBH4. X
ray powder diffraction pattern indicated the formation of CaB6 crystal, the field emission scanning electron microscope (FESEM)
image showed that CaB6 nanopowder was agglomerated with cubic crystals with grain size of ~80?nm. HRTEM photographs indicated
that the nanoparticles were singlecrystal corresponding to the FESEM and XRD results, and the CaB6 crystal consisted well
crystallized CaB6 core and thin amorphous shell (4~5?nm). Fourier transform Infrared (FTIR) and UltravioletVisibleNear
Infrared (UVVISNIS) spectra were investigated to characterize optical properties of CaB6 nanopowder, compared with
micrometer CaB6 powders. Compared with the weak absorption bands of micronpowder, obvious Einstein shift and band broadening
occurred in nanopowder spectrum, which was thought to be related to lattice expansion and nanometer effect. UVVISNIS
spectrum showed that CaB6 nanopowder could absorb ultraviolet rays and the absorption peaks exist blue shift of spectrum,
compared with micron powder. In conclusion, CaB6 nanopowder showed absorbency within all the detected regions in FTIR and UV
VISNIS spectra, especially to the infrared.