Eu3+ Doped CaWO4—A Potential Red Long Afterglow Phosphor

Abstract

In this study, a series of Eu 3+ doped CaWO 4 phosphors were synthesized by the solid-state reaction method. Red long afterglow was observed after samples were excited with 254 nm. The main emission peaks were ascribed to the 5 D 0 -7 F J (J = 0, 1, 2, 3, 4) transitions of Eu 3+ , and the duration of the optimal sample could last nearly 40 min in the dark seen with naked eyes. The effect of the doping concentration of Eu 3+ and alkali metal charge compensators (Li, Na, K) on the luminescent properties of the products were investigated in detail. The proposed mechanism of this afterglow property is also discussed.

Structural investigation of the A-site vacancy in scheelites and the luminescence behavior of two continuous solid solutions A1–1.5xEux□0.5xWO4 and A0.64–0.5yEu0.24Liy□0.12–0.5yWO4 (A = Ca, Sr; □ = vacancy)

“…13,14 In the last decade, the potential of scheelite compounds as host materials for white-LEDs was extensively explored, such as Eu 3+ activated (Ca/Sr)BO 4 (B = W or Mo) are efficient LED red phosphors. [15][16][17][18][19] Moreover, great efforts have also been devoted to the synthetic methods in order to improve their luminescence performance. For example, in addition to the conventional high temperature solid-state reaction, other techniques like co-precipitation, combustion and hydrothermal methods were also employed, which can efficiently modify the crystal-size distribution and micromorphology of phosphors.…”

Luminescence properties of the pink emitting persistent phosphor Pr3+-doped La3GaGe5O16

“…Moreover, harmful gas is released in the synthetic process. In recent years, a few orange-red persistent phosphors have been reported such as MWO 4 :Eu 3+ /Sm 3+ (M ¼ Ca, Sr and Ba), [18][19][20] 23 etc. However, they are still far away from the expected target for orange-red persistent phosphors due to their unsatisfactory aerglow intensity or time.…”

Fabrication and Spectral Properties of Wood-Based Luminescent Nanocomposites

“…Owing to finite precision accuracy and sensibility of instruments, the long-lasting decay period has been recorded until it timed 585 min. Virtually, emitted light still can be observed by bare eyes after 11 h. The afterglow duration can be evaluated by the curve fitting method, and the original decay curve is fitted to the following equation [18][19][20]:…”