Sb_2MoO_6, Bi_2MoO_6, Sb_2WO_6, and Bi_2WO_6 flake-like crystals: Generalized hydrothermal synthesis and the applications of Bi_2WO_6 and Bi_2MoO_6 as red phosphors doped with Eu~(3+) ions

摘要

Under hydrothermal conditions, a series of flake-like Sb_2MoO_6, Bi_2MoO_6, SD_2WO_6, Bi_2WO_6 with the Aurivillius structure have been prepared controllably. It reveals that the initial molar ratios of SbCl_3-to-NaOH (or BiCl_3-to-NaOH) in the reaction system (SbCl_3-Na_2MoO_4, BiCl_3-Na2MoO_4, SbCl_3-Na_2WO_4, and BiCl_3-Na_2WO_4) play important roles in the determination of product phases. Besides, properly changing the content of NaOH involved can produce some unexpected phases such as orthorhombic Sb_2O_3 and tetragonal Bi_(12)O_(17)Cl_2. Moreover, substituting Bi~(3+) with Eu~(3+) at the A site is readily carried out because of their same valence states together with the similar ion radii. Consequently, the as-prepared Bi_2WO_6 and Bi_2MoO_6 samples have been doped with Eu~(3+) ions also under hydrothermal conditions to prepare the phosphors, which possess excellent red characteristics in terms of excitation and emission measurement. The present synthesis protocol has opened up an intriguing but effective avenue for producing antimony/bismuth-based materials, also exhibiting the potential application of red phosphors.