Near-infrared multi-wavelengths long persistent luminescence of Nd3+ ion through persistent energy transfer in Ce3+, Cr3+ co-doped Y3Al2Ga3O12 for the first and second bio-imaging windows

We developed a persistent phosphor of Y3Al2Ga3O12 doped with Nd3+, Ce3+, Cr3+ ions (YAGG:Nd-Ce-Cr) exhibiting long (10 h) persistent luminescence at multi-wavelengths of around 880, 1064, and 1335 nm due to f-f transitions of Nd3+ and at 505 nm due to Ce3+:5d1→4f transition. The intense near-infrared (NIR) persistent luminescence bands from Nd3+ match well with the first (650–950 nm) and second (1000–1400 nm) bio-imaging windows. The NIR persistent radiance of the YAGG:Nd-Ce-Cr phosphor (0.33 × 10−1 mW/Sr/m2) at 60 min after ceasing blue light illumination was over 2 times higher than that of the widely used ZnGa2O4:Cr3+ red persistent phosphor (0.15 × 10−1 mW/Sr/m2).