One-step synthesis of Sc2W3O12:Eu3+ phosphors with tunable luminescence for WLED

Sc 2 W 3 O 12 is an important host matrix for rare-earth doped luminescence. However, the conventional method to prepare the material is solid-state reaction, which results into coarse and irregular morphologies. In this work, Eu 3+ doped Sc 2 W 3 O 12 phosphors with high crystallinity and pure phase were successfully synthesized via one-step hydrothermal method . It was found that the crystalline phase changed from Sc 2 W 3 O 12 phase to Na 4 Sc 2 (WO 4 ) 5 phase when the molar ratio between Sc(NO 3 ) 3 and Na 2 WO 4 decreased. The temperature-dependent X-ray diffraction analysis was performed to prove the negative thermal expansion property of Sc 2 W 3 O 12 . A systematic study on the effect of reaction time, temperature and Eu 3+ doping concentration was explored. It was also found that the as-prepared samples displayed tunable emission colors, ranging from blueish white to orange red. Particularly, the white light emission with the chromaticity coordinate of (0.3395, 0.3289) can be realized in Sc 2 W 3 O 12 : 5% Eu 3+ . What's more, the photoluminescence properties of the samples were investigated under different ambient temperatures between 97 and 280 K. The result clearly showed energy transfer between Eu 3+ and WO 4 2− . The above results suggested that Sc 2 W 3 O 12 :Eu 3+ can be excellent candidate for solid-state lasing, panel display and WLEDs.