Role of Li⁺ion in the luminescence enhancement of lanthanide ions: favorable modifications in host matrices

Abstract

The effect of alkali ions on the modification of various host matrices and their effects on the luminescence properties of lanthanide ions have been demonstrated in this comprehensive review.

Facile route to produce spherical and highly luminescent Tb3+ doped Y2O3 nanophosphors

“…The nitro group around 1519 cm -1 and 1404 cm -1 has also displayed a decrease in S CP sample as compared to S P . The residual nitro group around 1500 cm -1 are called luminescence quenchers for rare earth emission and decreases the luminescence emission intensity [26][27][28][29]. These facts discussed above support that the use of polymers i.e.…”

Probing a new approach for warm white light generation in lanthanide doped nanophosphors

“…A similar phenomenon has been widely reported in Li + ion doped different types of matrices including Y 2 O 3 and summarized in a review article by our group. 20 It is to be noted here that, such interstitial occupancy by foreign ions appreciably changes crystal field symmetry around activator ions and, moreover to this, also causes evolution of vacancy in the material. Further, as the doping concentration of ZnO is increased, few additional peaks appear along with earlier observed shift towards higher 2θ value.…”

Improved optical photoluminescence by charge compensation and luminescence tuning in Ca6Ba(PO4)4O:Ce3+, Eu2+phosphors

“…The photoluminescence (PL) and photoluminescence excitation (PLE) spectra were carried out by a fluorescence spectrophotometer (F- 15 4600, HITACHI, Japan) equipped with a photomultiplier tube operating at 400 V and a 150 W Xenon lamp as the excitation source. The luminescence decay curves were obtained using a FLSP9200 fluorescence spectrophotometer (Edinburgh Instruments Ltd., U.K.), and an nF900 flash lamp was used as the 20 excitation resource. The internal quantum efficiency was measured using the integrated sphere on the same spectrophotometer, and white BaSO4 powder as a reference to measure the absorption.…”

“…Such a result means that observed enhanced photoluminescence cannot be ascribed to the different particle sizes or morphologies, and some other reasons will govern this. 20 Since the doped charge compensator ions, such as Li + , Na + , K + and Si 4+ will balance the charge induced by the non-equivalent substitution of Ce 3+ for Ca 2+ , thus it will increase the photoluminescence intensity in the corresponding system. 8 The following equations show the possible charge balance mechanism 25 without the addition of the charge compensator ions:…”