“…The excitation band centered at 288 nm could arise from charge transfer between the O ligand and the central Sn atom in the SnO6 octahedral group, while the excitation bands at 350, 426, 617 and 676 nm are ascribed to the 4 A 2 → 4 T 1 ( 4 P), 4 A 2 → 4 T 1 ( 4 F), 4 A 2 → 4 T 2 ( 4 F) and 4 A 2 → 2 E( 2 G) transitions of Cr 3+ ions, respectively. 34,35 For LZSO:0.03Ni 2+ phosphor, a broad emission centered at 1465 nm ranging from 1200–1750 nm (FWHM = 300 nm) was observed under excitation at 400 nm, derived from the 3 T 2 → 3 A 2 transition of Ni 2+ ions. At the same time, the sample has four peaks at 400, 426, 623, and 676 nm consisting of a continuous PLE spectrum monitored at 1465 nm, which originated from the 3 A 2 ( 3 F) → 3 T 1 ( 3 P), 3 A 2 ( 3 F) → 1 T 2 ( 1 D), 3 A 2 ( 3 F) → 3 T 1 ( 3 F) and 3 A 2 ( 3 F) → 1 E( 1 D) transitions of Ni 2+ ions, respectively.…”