화학공학소재연구정보센터
Materials Research Bulletin, Vol.46, No.6, 946-950, 2011
Synthesis, photoluminescence and magnetic properties of barium vanadate nanoflowers
The flower-shaped barium vanadate has been obtained by the composite hydroxide mediated (CHM) method from V(2)O(5) and BaCl(2) at 200 degrees C for 13 h. XRD and XPS spectrum of the as-synthesized sample indicate it is hexagonal Ba(3)V(2)O(8) with small amount of Ba(3)VO(4.8) coexistence. Scan electron microscope and transmission electron microscope display that the flower-shaped crystals are composed of nanosheets with thickness of similar to 20 nm. The UV-visible spectrum shows that the barium vanadate sample has two optical gaps (3.85 eV and 3.12 eV). Photoluminescence spectrum of the barium vanadate flowers exhibits a visible light emission centered at 492 and 525 nm which might be attributed to VO(4) tetrahedron with T(d) symmetry in Ba(3)V(2)O(8). The ferromagnetic behavior of the barium vanadate nanoflowers has been found with saturation magnetization of about 83.50 x 10(-3) emu/g, coercivity of 18.89 Oe and remnant magnetization of 4.63 x 10(-3) emu/g, which is mainly due to the presence of a non-orthovanadate phase with spin S = 1/2. (C) 2011 Elsevier Ltd. All rights reserved.