Doped zirconia phase and luminescence dependence on the nature of charge compensation

Abstract

Zirconia is a relatively new material with many promising practical applications in medical imaging, biolabeling, sensors, and other fields. In this study we have investigated lanthanide and niobium doped zirconia by luminescence and XRD methods. It was proven that charge compensation in different zirconia phases determines the incorporation of intrinsic defects and activators. Thus, the structure of zirconia does not affect the Er luminescence directly; however, it strongly affects the defect distribution around lanthanide ions and the way in which activator ions are incorporated in the lattice. Our results demonstrate the correlation between the crystalline phase of zirconia and charge compensation, as well as the contribution of different nanocrystal grain sizes. In addition, our experimental results verify the theoretical studies of metastable (tetragonal, cubic) phase stabilization determined using only oxygen vacancies. Moreover, it was found that adding niobium drastically increases activator luminescence intensity, which makes Ln3+ doped zirconia even more attractive for various practical applications. Although this study was based on the luminescence of the Er ion, the phase stabilization, charge compensation, and luminescence properties described in our results are expected to be similar for other lanthanide elements. Our results suggest that the luminescence intensity of other oxide matrices where lanthanides incorporate in place of tetravalent cations could be increased by addition of Nb ions.

The influence of chemical prehistory on the structure, photoluminescent properties, surface and biological characteristics of Zr0.98Eu0.02O1.99 nanophosphors

“…Selectivity for the excitation wavelength, energy transfer efficiency, lifetime and quantum yield of photoluminescence are determined mainly by the structure and size of ZrO 2 crystals, as well as the concentration and localization of Ln 3+ active centers in them [26][27][28][29]. The distribution of trivalent lanthanide ions between the amorphous, monoclinic and more symmetrical tetragonal and cubic phases of ZrO 2 can be adequately distinguished using Eu3+ as a probe.…”

Synthesis, characterization and luminescence properties of ZrBDC:Eu3+,Tb3+ nanoscaled metal organic frameworks

“…[4][5][6] Together with Zr-MOF, the zirconia doped with rare earth ions (ZrO2:RE 3+ ) is also a promising materials for many potential applications in fields of photonics, optoelectronics and biomedical because of its wide band-gap, high chemical stability, mechanical, refractive index and optical transparency. [7][8] In addition, the ZrO2:RE 3+ have narrow emission peaks, large Stokes shift, long lifetime, high quantum efficiency, good optical stability. [7,8] Currently, there are many ways of preparing the ZrO2:RE 3+ nanomaterials, such as colloidal, coprecipitation, combustion, sol-gel, sonochemistry, hydrothermal and microwave-assisted methods.…”

“…[7][8] In addition, the ZrO2:RE 3+ have narrow emission peaks, large Stokes shift, long lifetime, high quantum efficiency, good optical stability. [7,8] Currently, there are many ways of preparing the ZrO2:RE 3+ nanomaterials, such as colloidal, coprecipitation, combustion, sol-gel, sonochemistry, hydrothermal and microwave-assisted methods. [7][8][9] Nowadays, there is an emerging trend in preparing the ZrO2 nanoparticles based metal organic frameworks.…”

“…[7,8] Currently, there are many ways of preparing the ZrO2:RE 3+ nanomaterials, such as colloidal, coprecipitation, combustion, sol-gel, sonochemistry, hydrothermal and microwave-assisted methods. [7][8][9] Nowadays, there is an emerging trend in preparing the ZrO2 nanoparticles based metal organic frameworks. [10] In this study, we used the nanoscaled metal organic frameworks of ZrBDC:RE 3+ as precursors for the manufacture of ZrO2:RE 3+ nanoparticles (RE = Eu, Tb) via heat treatment process at 800 o C for 1 hour.…”

Phase composition and photoluminescence correlations in nanocrystalline ZrO2:Eu3+ phosphors synthesized under hydrothermal conditions

“…The change in the luminescence intensity and the phase transition from ZrO 2 equilibrium modification to metastable tetragonal and even cubic occurs with an increase of the lanthanide content in its crystal lattice. For stabilizing the tetragonal phase, it is usually necessary to add up to 6 mol.% of the trivalent ions, whereas the required concentration to achieve the cubic phase is 10 -12 mol.% [27]. The tetragonal with or separately from the monoclinic phase of ZrO 2 are formed depending on the synthesis method at a low concentration of Ln 3+ ions.…”