Preparation and Luminescence Properties of the Na₂W₂O₇ Crystal

We discuss the synthesis of Na₂W₂O₇ polycrystalline materials based on the TG−DSC experiment. The luminescence properties of the Na₂W₂O₇ crystal are investigated using the Nd:YAG laser as the excitation source. It is found that the maximum emission peak of the Na₂W₂O₇ crystal is at 525 nm. The 525−nm luminescence decay has two components. One has decay time 1.8 µs and the other 49.1 µs. By comparing this results with that of the Na₂W₄O₁₃ crystal, it is assumed that the 525−nm luminescence emission of the Na₂W₂O₇ crystal originates from the WO₆⁶⁻ octahedral group.