Insight into the optical absorption and luminescent properties due to the presence of Pr4+ in Pr-doped Y2O3
Por:
López-Pacheco G., Padilla-Rosales I., Miguel-Eugenio A., Barrera-Calva E., Rosas R., González F.
Publicada:
1 ene 2022
Resumen:
Powder samples of undoped and Pr-doped Y2O3 are synthesized by the reverse precipitation method and annealed at 1000 °C for 1 h. X-ray diffraction patterns confirm the presence of the well-known Y2O3 cubic phase. The optical properties of the compounds are characterized by diffuse reflectance and photoluminescence spectroscopies. The presence of a huge absorption band in the Pr-doped samples is attributed to the presence of Pr4+, but also emission and excitation luminescent spectra reveal the existence of Pr3+. To explain the origin of the broad absorption band, it is made use of an approach formulated decades ago based on the assumption that ligand-to-metal charge transfer states O2-/- ? Pr4+/3+ are involved. To implement this approach, a deconvolution of the absorption spectrum, following a judicious conjecture based on phenomenological methods in which each deconvolution's component is associated with a transition from the top of the valence band, mainly O-2p in character, to each of the Pr3+ f-f states, or from the Pr3+-3H4 ground state to one of its d states, is performed. Our results match consistently with those energies calculated from a vacuum referred binding energy diagram, allowing to rationalize the presence of a huge absorption band as well as to explain the absence of the emission coming from the most energetic Pr3+ electronic transitions when Pr4+ is present in Pr-doped Y2O3. © 2021 Elsevier B.V.
Filiaciones:
López-Pacheco G.:
Departamento de Ingeniería de Procesos e Hidráulica, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-534, Ciudad de México, Mexico
Padilla-Rosales I.:
Departamento de Ingeniería de Procesos e Hidráulica, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-534, Ciudad de México, Mexico
Miguel-Eugenio A.:
Licenciatura en Ingeniería en Energía, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-534, Ciudad de México, Mexico
Barrera-Calva E.:
Departamento de Ingeniería de Procesos e Hidráulica, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-534, Ciudad de México, Mexico
Rosas R.:
Departamento de Ingeniería de Procesos e Hidráulica, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-534, Ciudad de México, Mexico
González F.:
Departamento de Ingeniería de Procesos e Hidráulica, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-534, Ciudad de México, Mexico
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