Influence of trap centers on persistent luminescence of Cr 3+ or Yb 3+ Co‐doped Y 3 Al 2 Ga 3 O 12 :Pr 3+ ceramic phosphors

Abstract Lanthanide ion doped garnet is one of the representative persistent luminescence (PersL) phosphors that have been widely investigated. However, the role of the trap centers, either intentionally added co‐dopants or intrinsic defects arising during the sintering process, and their effect on the performance of PersL has not been completely elucidated, especially when they coexist. In pursuit of clarifying the relationship among different trap centers and their impact on the afterglow, herein, low‐concentration Pr 3+ and Cr 3+ /Yb 3+ (electron trap) co‐doped Y 3 Al 2 Ga 3 O 12 ceramic phosphors are synthesized using a solid‐state reaction method under a vacuum atmosphere and some of them are further subjected to annealing condition. The observed thermoluminescence glow curves are composed of two strong peaks related to oxygen vacancies and a weak peak formed by each Cr and Yb trap based on the relative concentration ratio. On the other hand, it is found that the Cr 3+ and Yb 3+ ions act as prominent near‐infrared (NIR) PersL centers in the NIR‐I and NIR‐II region, respectively, matching with the first and the second biological window. This work allowed for an exploration of the properties of distinct trap centers and how they influence the PersL and are likely to hasten the development of new PersL materials.