Surface Characterization and Photoluminescence Properties of Ce3+,Eu Co-Doped SrF2 Nanophosphor

Abstract

SrF2:Eu,Ce3+ nanophosphors were successfully synthesized by the hydrothermal method during down-shifting investigations for solar cell applications. The phosphors were characterized by X-ray diffraction (XRD), scanning Auger nanoprobe, time of flight-secondary ion mass spectrometry (TOF-SIMS), X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) spectroscopy. XRD showed that the crystallite size calculated with Scherrer’s equation was in the nanometre scale. XPS confirmed the formation of the matrix and the presence of the dopants in the SrF2 host. The PL of the nanophosphor samples were studied using different excitation sources. The phenomenon of energy transfer from Ce3+ to Eu2+ has been demonstrated.

Enhanced Power Conversion Efficiency Using a Ce3+:SrF2 Down-Shifting Nanophosphor-Based Photoelectrode for Dye-Sensitized Solar Cell Applications

“…The XPS spectrum of Sr 3d is deconvoluted into the peaks at 133.5 and 135.3 eV (Figure b). These are assigned to the 3d 5/2 and 3d 3/2 orbitals occurring from spin–orbit splitting of the Sr 3d state in the SrF 2 host lattice, respectively Figure c reveals the presence of characteristic F 1s state with the peak at 687.4 eV.…”

“…The core-level XPS graph of Ce 3d is depicted in Figure d. It consists of two peaks at 885.3 and 889.8 eV, which are respectively assigned to the spin–orbital interaction of 3d 5/2 and 3d 3/2 states of Ce 3+ ions, respectively . In addition, the satellite peak at 876.6 eV is due to the F KLL Auger electron …”

Ce3+/Eu2+ Doped Al2O3 Coatings Formed by Plasma Electrolytic Oxidation of Aluminum: Photoluminescence Enhancement by Ce3+→Eu2+ Energy Transfer

“…The For further investigation of the chemical nature and oxidation state of Ce and Eu in created coatings, we recorded a high-resolution Ce 3d and Eu 3d core-level spectra of Ce and Eu doped Al 2 O 3 coating created in supporting electrolyte with the addition of 4 g/L CeO 2 + 4 g/L Eu 2 O 3 particles ( Figure 3). The peak deconvolution of the high-resolution XPS peaks of Ce 3d shows that the level of Ce ion is composed of four Gaussian peaks, i.e., two pairs of doublets (3d 5/2 at 881.5 eV and 885.3 eV, 3d 3/2 at 899.5 eV and 903.9 eV), characteristic for Ce 3+ oxidation state [18]. The Eu 3d core level spectrum consists of two doublets: (i) The Eu 3d 5/2 (at 1135.3 eV) and Eu 3d 3/2 (at 1165.3 eV) peaks, attributed to Eu 3+ oxidation state, and (ii) at lower binding energies at ca.…”

Synthesis and quantum yield investigations of the Sr(1-x-y)Pr(x)Yb(y)F(2+x+y) luminophores for photonics

“…It should also be noted that the quantum yield of up-conversion luminescence is not high and usually stays at the level of few percents. Solid solutions powders based on SrF 2 doped by rare earth elements can be synthesized by different techniques: co-precipitation from aqueous solutions by various fluorinating agents such as HF, NH 4 F, KF, NaF [13][14][15], sol-gel processing in organic solution [16], combustion [17] and hydrothermal synthesis [18][19][20]. Sol-gel processing in organic solution used gaseous HF, which is very dangerous.…”