Efficient and broadband Na4Al3Ta(PO4)6:Cr3+ phosphors for NIR pc-LED application

Cr 3+ -activated phosphate-based near-infrared (NIR) luminescent materials offer a unique advantage in terms of preparation conditions. To achieve outstanding material properties, the selection of suitable octahedra is crucial. In this paper, a novel phosphate NIR phosphor, Na 4 Al 3 Ta(PO 4 ) 6 :Cr 3+ (NAT:Cr 3+ ), is reported by searching for materials containing AlO 6 octahedral. Under the excitation of 456 nm, NAT:Cr 3+ shows a broadband emission centered at 820 nm with an internal quantum efficiency of 59.7 %. The prepared NIR LED exhibits an output power of 50.9 mW at an input power of 272 mW (2.72 V, 100 mA), demonstrating the potential application in blue LED-based NIR spectroscopy .