Emission of 153 μm originating from the lattice site of Er^3+ ions incorporated in TiO_2 nanocrystals

Abstract

Er(3+)-ion-doped anatase TiO(2) nanocrystals were prepared by simple wet chemical synthesis. Very sharp and intense near-infrared luminescence at approximately 1.53 microm was observed that originated from the lattice site of Er(3+) ions incorporated in TiO(2) nanocrystals. Based on the high-resolution emission and excitation spectra at 10 K, an efficient energy transfer from the TiO(2) host to Er(3+) ions was verified. The luminescence decay for the I13/24-->I15/24 transition at 1.53 microm showed nonexponential characteristics, indicating a nonradiative relaxation to the defects in the nanocrystals, and the intrinsic lifetime of the I13/24 state was determined to be 1.56 ms.

Optical spectroscopy of lanthanides doped in wide band-gap semiconductor nanocrystals

“…Interestingly, by slightly modifying the synthesis condition (reaction temperature), only one single lattice site emission of Er 3 + in TiO 2 NCs was obtained in spite of the large mismatch of ionic radius and charge imbalance between Er 3 + and Ti 4 + [14], which was very different from that observed in Eu 3 + ions doped TiO 2 NCs. lines of Er 3 + centered at 380.6, 407.6, 489.4, 523.4, 550.5 and 654.0 nm were observed, which corresponded to the direct excitation from ground state of 4 I 15/2 to the upper excited states of 4 G 11/2 , 2 H 9/2 , 4 F 7/2 , 2 H 11/2 , 4 S 3/2 and 4 F 9/2 , respectively.…”

“…We expect that the incorporation of various Ln 3 + ions in the lattices of semiconductor NCs can lead to sharp and multicolor emissions from Ln 3 + to meet the increasing demands for highly sensitive biolabeling, lighting and displays. Very recently, utilizing facile sol-gel and solvothermal methods, we have successfully incorporated Ln 3 + ions in the lattices of different semiconductor NCs such as ZnO, SnO 2 , TiO 2 and In 2 O 3 [9][10][11][12][13][14][15]. As a result, intense and sharp emission lines of Ln 3 + ions have been realized in most semiconductor NCs via host sensitization.…”

Host-sensitized multicolor tunable luminescence of lanthanide ion doped one-dimensional YVO4 nano-crystals

“…To achieve highly efficient multicolor tunable luminescence of lanthanide ions, host sensitization via energy transfer from the excited host to the Ln 3+ ions is an effective way to overcome the low absorptions of parity forbidden 4f-4f transitions of Ln 3+ [4][5][6][7]. Semiconductor nano-crystals (such as ZnO, In 2 O 3 , TiO 2 , and SnO 2 ) have been considered as promising candidates for such hosts and sensitizers due to the ease to tailor their optical properties via size or morphology control [8][9][10][11][12][13]. However, owing to the necessary charge compensation or the unmatched radius between Ln 3+ and cations of semiconductor, doping of high content of Ln 3+ into the semiconductor nano-crystals is very tough [14].…”

Low-voltage driven visible and infrared electroluminescence from light-emitting device based on Er-doped TiO2/p+-Si heterostructure

“…At the wavelengths peripheral to the above-mentioned peaks, the presence of some shouldering peaks is associated with the transitions between different splitting levels generated by the Stark effect. 17 Figure 2(b) displays the decay trace of the $1540 nm emission, which can be described by a stretched exponential decay function. The best-fit of the decay trace derives a lifetime (s) of $0.61 ms, which is much larger than that for Er-doped SiO x film 18 but lower than that for Er-doped silicon nitride film.…”