CdSiO3, with its distinctive crystal structure, has become a subject of considerable interest as a potential silicate host for long persistent luminescence (LPL) phosphors. However, in most cases, impurity phases in the host adversely affect the persistent luminescence (PersL) performance. Furthermore, there is still a lack of insightful understanding regarding the role of non-rare-earth (non-RE) In3+ ions in the enhanced blue PersL of CdSiO3. Here, pure-phase monoclinic CdSiO3 phosphor is synthesized through a solid-state reaction method and the intense blue PersL is achieved by aliovalent doping of In3+. Combining experimental results with theoretical calculation, we reveal that the intrinsic defects of O and Cd vacancies in CdSiO3 are the trap centers for excited electrons and holes, respectively. In3+ doping adjusts the distribution and increases the density of intrinsic defect-related traps, thus producing the intense blue PersL in CdSiO3:In3+. Moreover, the generality of In3+ in enhancing the PersL properties is validated in CdSiO3:Mn2+,In3+ and CdSiO3:RE3+,In3+ (RE = Tb, Dy, Pr, Sm, Eu) phosphors, enriching the spectrum of PersL emission colors. Encouraged by the outstanding optical properties of CdSiO3:Mn2+,In3+, we demonstrate dual-mode information storage-reading and dynamic information encryption applications. This advancement opens new avenues for the application of optical information security. This work emphasizes the key role of In3+ in adjusting the distribution and increasing the density of intrinsic defect-related traps. Consequently, it reveals a clear mechanism for enhancing PersL through In3+ doping and expands the range of LPL phosphors with broad spectral selectivity.
Read full abstract