Optical and magnetic properties induced by structural confinement of ternary chalcogenide in SBA-15 nanotube.

The amorphous ternary material, Ni[SUB3](SbTe[SUB3])[SUB2] was prepared using a rapid precipitation reaction between the Zintl phase K[SUB3]SbTe[SUB3] and NiBr[SUB]2 in solution. This material induced by the incorporation) of ternary chalcogenide into long range ordered mesoporous SBA-15 was transformed into ternary nanoparticles. Structural confinement of the amorphous ternary chalcogenide in the mesoporous silica tube causes the suppression of phonon coupling to photoexcited carriers in the confined ternary chalcogenide, resulting in narrower photoluminescence (PL) band than those of the bulk ternary chalcogenide. It also gives rise to ferromagnetic behavior of the nanoparticles made from the material, which is a spin glass with the freezing temperature of 4.0 K in a bulk form. The physical and chemical properties of obtained ternary bulk and nanoparticles have been investigated by x-ray diffraction, superconducting quantum interference device, transmission electron microscopy, Brunauer - Emmett -- Teller, and PL (steady-state photoluminescence spectroscopy). The role played by the modified SBA-15 porous silica in controlling ternary chalcogenide size and quantities has been discussed. [ABSTRACT FROM AUTHOR]