Investigation on Eu/Tb activated photoluminescent properties of Li 3 Sc(BO 3 ) 2 based phosphors

Two new rare-earth borates Sr2Tb3B27−δO46 and Ba2Eu3B27−δO46 (δ = 2/3): syntheses, crystal structures, and luminescence properties

“…Therefore, Tb 3+ in a specific host exhibits two sets of f–d transitions: one is high-energy spin-allowed (SA) and another is low-energy spin-forbidden (SF). 60 In addition, the crystal-field and the spin–orbit interactions for the 5d electrons as well as the Coulomb interactions between the 4f and the 5d electrons made the 4f5d states of Tb 3+ more complicated. Thus, a broad band peak at 252 nm with a shoulder at 280 nm is considered to be the SA 4f 8 → 4f 7 5d 1 ( 7 F 6 – 7 D J ) and SF 4f 8 → 4f 7 5d 1 ( 7 F 6 – 9 D J ) transitions of Tb 3+ ions, respectively.…”

Structure, tunable luminescence and energy transfer in Tb3+ and Eu3+ codoped Ba3InB9O18 phosphors

“…Simultaneously, the rest of the Tb 3+ ions with the 5 D 4 excited state transfer their energy to the 5 D 1 excited state of Eu 3+ ions, leading to red emission from Eu 3+ ions through 5 D 0 -7 F J (J ¼ 0-6) transitions. [37][38][39]…”