Tuning into single-band red upconversion luminescence in Yb³⁺/Ho³⁺ activated nano-glass-ceramics through Ce³⁺ doping

Abstract

Yb(3+)/Ho(3+) activated glass ceramics containing β-YF3 nanocrystals were successfully fabricated. The green ((5)S2/(5)F4→(5)I8) upconversion emission is dominant in the glass ceramics and is about 160 times stronger than that of the precursor glass, resulting from the partition of lanthanide activators into a low-phonon-energy crystalline lattice and the subsequent low probability of multi-phonon nonradiative relaxation from the (5)S2/(5)F4 and (5)I6 states to the lower ones. Upon the introduction of Ce(3+) ions into nano-glass-ceramics, two efficient cross-relaxation processes between Ho(3+) and Ce(3+), i.e., Ho(3+):(5)S2/(5)F4 + Ce(3+):(2)F5/2→Ho(3+):(5)F5 + Ce(3+):(2)F7/2 and Ho(3+):(5)I6 + Ce(3+):(2)F5/2→Ho(3+):(5)I7 + Ce(3+):(2)F7/2, are demonstrated to greatly suppress the population of the green-emitting (5)S2/(5)F4 state and to enhance the population of the red-emitting (5)F5 one, leading to the intense single-band red UC radiation of Ho(3+).

Exploring pure and RE co-doped (Eu3+, Tb3+ and Dy3+) gadolinium scandate: Luminescence behaviour and dynamics of energy transfer

“…[1][2][3].A completely new host calcium gallium germanium garnet has demonstrated wherein Cr/Yb/Tm:Ca 3 Ga 2 Ge 3 O 12 phosphor exhibits both broadband near-infrared long-lasting phosphorescence of Cr 3+ with an afterglow time of more than 7000 s and near-infrared to near-infrared upconversion luminescence of Tm3+ [4].…”

CeIV–GdIII Mixed Oxides as Hosts for ErIII‐Based Upconversion Phosphors

“…[6] The majority of compounds that can undergo UC involve trivalent lanthanides, Ln III ,b ecause thesec entres have more than one metastable level, with excited-state lifetimes typicallyi nt he range of 10 À6 -10 À2 s, being the basic requirement for UC. Lanthanides have been hostedw ithin several matrices such as fluorides, [8][9][10] oxides, [11,12] phosphates, [13] and vanadates. As ac onsequence, luminescence processes are much more competitive than multiphonon relaxation in lanthanides,a sc ompared with other centres.…”

“…As ac onsequence, luminescence processes are much more competitive than multiphonon relaxation in lanthanides,a sc ompared with other centres. Lanthanides have been hostedw ithin several matrices such as fluorides, [8][9][10] oxides, [11,12] phosphates, [13] and vanadates. [14] Certain rare-earth (RE) based oxides such as CeO 2 [15,16] or Gd 2 O 3 [17][18][19] offer highly biocompatibleh osts for Er III -based UC phosphors, with relevantbiomedical functionalities.…”

Preparation and optical properties of Eu 3+ doped and Er 3+ /Yb 3+ codoped oxyfluoride glass ceramics containing Ba 1−x Lu x F 2+x nanocrystals

“…Oxyfluoride glass ceramic seems to be an ideal host matrix for RE ions, in which fluoride nanocrystals could provide a low-phonon-energy environment and oxide glass could keep the high mechanical and chemical stability [7][8][9]. Moreover, the fluoride nanocrystals are precipitated from the precursor oxyfluoride glass during the controllable crystallization process and RE ions are preferentially concentrated in the fluoride nanocrystals.…”