Deep-red persistent luminescence in Cr³⁺-doped LaAlO₃perovskite phosphor for in vivo imaging

Abstract

We report deep-red long-lasting persistent luminescence in Cr3+-doped LaAlO3 perovskite phosphor synthesized by solid-state reaction. The LaAlO3:Cr3+ sample showed persistent luminescence peaking at a very long wavelength of 734 nm due to Cr3+:2E → 4A2 transition after ultraviolet excitation. The Sm3+ ion was found to be a good codopant for increasing the persistent luminescence intensity more than 35-fold. For the Cr3+–Sm3+-codoped LaAlO3 sample, the radiance of persistent luminescence in mW sr−1 m−2 unit was higher than or comparable to that of ZnGa2O4:Cr3+ phosphor, which is a candidate phosphor with a peak luminescence at 694 nm for in vivo imaging application.

Persistent luminescence properties of Cr^3+-Sm^3+ activated LaAlO_3 perovskite

“…Cr 3+ activated LaAlO 3 compound shows zero phonon lines (R-line, 2 E→ 4 A 2 transition) at 734 nm at longer wavelength compared with other well-known Cr 3+ activated oxides, for instance 694 nm in Al 2 O 3 and in ZnGa 2 O 4 . This nature is due to the small Racah parameters of Cr 3+ in this perovskite structure [10,11]. In previous study, we reported that LaAlO 3 :Cr 3+ phosphors show deep-red persistent luminescence after UV light excitation.…”

LaAlO3:Mn4+ as Near-Infrared Emitting Persistent Luminescence Phosphor for Medical Imaging: A Charge Compensation Study

“…In the present work, manganese doped perovskite lanthanide aluminates (LaAlO 3 ) were synthesized by a high-temperature solid-state reaction method, similar to other reported work [19,24,25] and the persistent luminescence behavior was optimized. In order to improve the near-infrared persistent luminescence intensity of LaAlO 3 :Mn 4+ phosphors, a series of samples were prepared using solid state reaction in air through co-doping with a variety of ions with different valence states.…”

Chemically engineered persistent luminescence nanoprobes for bioimaging

“…Among the different possibilities, we can cite preliminary works on perovskites reported by Tanabe and co-workers 145 and works concerning PLNPs emitting in the second transparency window reported by Ueda and co-workers 146 and Pan and co-workers 147. A limit with current probes is their long term chemical stability in vivo .…”