Effect of Eu3+ - dopant concentration on structural and luminescence properties of SrY2O4 nanocrystalline phosphor and potential application in dye-sensitized solar cells

Abstract

SrY 2 O 4 phosphors were doped with different concentrations of Eu 3+ (0.5, 1, 2, 4, 8 and 10 at %) in order to investigate the maximal doping concentration of Eu 3+ and its implementation in solar cell devices. Samples were synthesized by a combustion method using citric acid and glycine as a fuel. The X-ray diffraction (XRD) patterns confirmed pure phase of SrY 2 O 4. FE-SEM micrographs showed agglomerate phenomenon with spherical-like shape particles and diameter of about 50 nm. Upon excitation with 280 nm, emission spectra were recorded in the range from 450-750 nm and in all samples the same energy transitions were observed 5 D 0 → 7 F J (J = 1, 2, 3 and 4) with maximal intensity for sample with 8 at % of Eu 3+. That sample was further examined for the purpose of application in solar cell devices and showed high value of efficiency at low light intensities.

Structural and luminescence studies of titanium co‐doped SrY2O4:Eu phosphors

“…Y 3+ ions are surrounded by six oxygen atoms at both places and the Sr 2+ ions are surrounded by eight oxygen atoms. [ 9,10 ] The dopant atom may substitute any of these two Y sites.…”

“…Y 3+ ions are surrounded by six oxygen atoms at both places and the Sr 2+ ions are surrounded by eight oxygen atoms. [9,10] The dopant atom may substitute any of these two Y sites. SrY 2 O 4 is an efficient host matrix for the doping of many rareearth ions due to similarity in ionic radii and valency.…”

Structural and luminescence properties of SrGd2O4 nanocrystalline phosphor doped with Dy3+ and Sm3+

“…Binary rare earth oxides with general formula ARE 2 O 4 (A = Ca, Sr, Ba, RE = trivalent rare earth elements) are gathering significant importance for examining luminescent properties due to their specific optical, thermal and magnetic properties [7,8]. Particularly, for us is interesting SrGd 2 O 4 , although it has shown some very promising properties such as good charge stability, excellent thermal stability, refractive index (n≈2), high density (~7.3 g/cm 3 ) and high chemical robustness, it has not been extensively researched [9][10][11][12][13][14][15].…”

“…Also, some authors indicated that the luminescent properties of a host material can be improved by incorporating various metal ions. Wang et al investigated photoluminescence properties of SrGd 2 O 4 :Eu 3+ red phosphor synthesized by high-temperature solid-phase method [8]. The authors experimented with various doping concentrations of Eu 3+ (1-15 at%) and achieved the best red emission at 611 nm, caused by 5 D 0 → 7 F 2 transition (λ ex =267 nm) at 5at% Eu 3+ dopant concentration.…”