Luminescence properties of Tb³⁺ doped Gd₂(WO₄)₃ phosphor prepared by hydrothermal method

The Gd₂(WO₄)₃:Tb³⁺ phosphors have been successfully prepared using the hydrothermal method calcined at 900°C in this work. The crystal structure, PLE/PL and fluorescence decay behavior of samples were investigated in detail. Under the 270 nm excitation (4f⁸→4f⁷⁵d¹ transition of Tb³⁺), the (Gd_2-xTb_x)(WO₄)₃ (x=0.01-0.15) phosphors emit the strong green emission at 547 nm (5D₄→⁷F₅ transition of Tb³⁺). The quenching concentration was found to be ∼10% owing to the exchange reaction between Tb³⁺. The Tb³⁺ addition did not influence the CIE chromaticity coordinates (∼0.33±0.02, ∼0.60±0.02) and color temperatures (∼5542 K) of the (Gd_2-xTb_x)(WO₄)₃ phosphors. However, due to the energy transfer between Tb³⁺, the fluorescence lifetime for 547 nm emission decreased with the Tb³⁺ content increasing. The Gd₂(WO₄)₃:Tb³⁺ phosphors with strong green emission are expected to be widely used in white light LED and display areas. (paper)