Erbium-to-dysprosium energy-transfer mechanism and visible luminescence in lead-cadmium-fluorogermanate glass excited at 405 nm

The Effect of Linker‐to‐Metal Energy Transfer on the Photooxidation Performance of an Isostructural Series of Pyrene‐Based Rare‐Earth Metal–Organic Frameworks

“…Diffuse reflectance UV–vis (DR‐UV–vis) spectroscopy performed on RE‐CU‐10 analogues as well as the free linker, which exists as the porous hydrogen‐bonded organic framework (HOF) HOF‐101 [ 82 ] (also called PFC‐1, Figure S26, Supporting Information), [ 83 ] shows pyrene‐based absorption from 250–450 nm with a steep decrease and tail extending to the visible region of the spectrum up to ~620 nm ( Figure ; Figure S27, Supporting Information). [ 84 ] Ho‐, Er‐, and Tm‐CU‐10 also show metal‐based absorption bands in the visible region, positioned at 537 nm ( 5 I 8 → 5 F 4 ) and 640 nm ( 5 I 8 → 5 F 5 ) for Ho‐CU‐10, [ 85 ] 520 nm ( 4 I 15/2 → 2 H 11/2 ) and 652 nm ( 4 I 15/2 → 4 F 9/2 ) for Er‐CU‐10, [ 85,86 ] and 683 nm ( 3 H 6 → 3 F 3 ) and 767 nm ( 3 H 6 → 3 H 4 ) for Tm‐CU‐10. [ 85 ] Upon linker excitation at 395 nm, RE‐CU‐10 shows a broad emission band, with a maximum at 465 nm (Y‐CU‐10), 504 nm (Gd‐CU‐10), 507 (Tb‐CU‐10), 512 nm (Dy‐CU‐10), 498 nm (Ho‐CU‐10), 458 nm (Er‐CU‐10), 489 nm (Tm‐CU‐10) and 453 nm (Yb‐, Lu‐CU‐10) consistent with pyrene‐based emission (Figure 3b; Figure S28, Supporting Information).…”

“…[90,91] H 4 TBAPy has a T 1 energy of ~16 900 cm −1 , [71] which lies below an emitting state of Gd(III), Tb(III) and Dy(III), but above an emitting state of Ho(III), Er(III), Tm(III), and Yb(III) (Table 1). [92] More specifically, the H 4 TBAPy T 1 energy is lower than the 6 P 7/2 emitting state of Gd(III), [93] 5 D 4 of Tb(III), [71] 4 I 15/2 and 4 F 9/2 of Dy(III), [94] 5 S 2 of Ho(III), [95] 4 S 3/2 of Er(III), [86,96] 1 D 2 and 1 G 4 of Tm(III) [97] hindering the linker-to-metal energy transfer (Table 1).…”

The Effect of Ligand-to-Metal Energy Transfer on the Photooxidation Performance of an Isostructural Series of Pyrene-Based Rare-Earth Metal–Organic Frameworks

“…89,90 H4TBAPy has a T1 energy of ~16 900 cm -1 , 71 which lies below an emitting state of Gd(III), Tb(III) and Dy(III), but above an emitting state of Ho(III), Er(III), Tm(III) and Yb(III) (Table 1). 91 More specifically, the H4TBAPy T1 energy is lower than the 6 P7/2 emitting state of Gd(III) 92 , 5 D4 of Tb(III), 71 4 I15/2 and 4 F9/2 of Dy(III), 93 5 S2 of Ho(III), 94 4 S3/2 of Er(III), 85,95 1 D2 and 1 G4 of Tm(III) 96 hindering the linker-tometal energy transfer (Table 1). On the other hand, the H4TBAPy T1 energy is higher than the 5 F5 emitting state of Ho(III), 97 4 I13/2 of Er(III), 98,99 3 H4 of Tm(III) 100 and 2 F5/2 of Table 1: Summary of energy levels of electronic states of the organic linker and RE(III) ions.…”