Enhancement of Multicolor Luminescence of GdVO4 Core-Shell Structure via TiO2 Interlayer

• Published in: Russian Journal of Physical Chemistry A 2021-12, Vol.95 (13), p.2714-2719
• Main Authors: Wei-jun Gui, Suo, Teng-yuan, Chen, Xiao-ling, Zhang, Xiao-hang
• Format: Article
• Language: English
• Subjects: Annealing furnaces; Chemistry; Chemistry and Materials Science; Chromaticity; Core-shell structure; Emission spectra; Energy transfer; Europium; Excitation spectra; Interdiffusion; Interlayers; Luminescence; Muffle furnaces; Phosphors; Photochemistry and Magnetochemistry; Physical Chemistry; Shells; Sodium citrate; Titanium dioxide; White light
• ISSN: 0036-0244; 1531-863X
• DOI: 10.1134/S0036024421130094

By using sodium citrate as complexing and capping agent, GdVO 4 core-shell structures (CSSs) were prepared via hydrothermal method, with Dy 3+ and Eu 3+ doped into the core and shell layer, respectively. The as-prepared CSSs were then annealed at 600°C for 2 h in muffle furnace. XRD and TEM results show that crystalline phase of the well-dispersed CSSs is tetragonal phase. To avoid interdiffusion of Dy 3+ and Eu 3+ during annealing process, i.e., to prevent energy transfer from Dy 3+ to Eu 3+ , TiO 2 interlayer was inserted between the core and shell layer. The normalized emission spectra at the excitation wavelength of 253 or 340 nm prove that TiO 2 interlayer can significantly enhance luminescence of Dy 3+ ions. Besides, CIE ( x , y ) chromaticity coordinate diagram analysis shows that the CSS with TiO 2 interlayer provide much better multicolor luminescence performance than other materials. The experimental scheme presented in the context provides a feasible way to find high-quality phosphors for UV-excitated white light-emitting diod (WLED).