Study on the effects of 5d energy locations of Ce^3+ ions on NIR quantum cutting process in Y_2SiO_5: Ce^3+, Yb^3+

Abstract

The effects of the 5d energy locations of Ce³⁺ centers on the NIR quantum cutting process were studied in Y₂SiO₅ with two different substitutional Y³⁺ lattice sites for Ce³⁺ and Yb³⁺. Powder XRD and Rietveld refinement were used to characterize phase purity, crystal structure, lattice parameters and occupation fractions of Y₂₋x-yCexYbySiO₅ (x = 0.002 and 0.3, y = 0-0.2). PLE and PL spectra show that both kinds of Ce³⁺ centers in Y₂x-yCexYbySiO₅ can cooperatively transfer energy to Yb³⁺-Yb³⁺ ions pair. The dependence of the integrated emission intensities of Ce³⁺ and Yb³⁺, decay lifetime (τ) of Ce³⁺, nonradiative energy transfer rate (KCe→Yb), cooperative energy transfer efficiency (ηCET) and quantum efficiency (ηQE) on the concentration of Yb³⁺ ions were studied in details. More importantly, these results demonstrate that the 5d energy locations of Ce³⁺ ions have a great influence on NIR quantum cutting process in Ce³⁺-Yb³⁺ system: the closer they are to twice the absorption energy (~20000 cm⁻¹) of Yb³⁺, the higher the cooperative energy transfer efficiency from the lowest 5d excited state of Ce³⁺ to the Yb³⁺-Yb³⁺ ions pair.

Yb3+ site occupation and host sensitization luminescence of a novel near‐infrared emitting Sr2CaMoO6:Yb3+ phosphor

“…The appearance of the CTB of MoO 6 group in the excitation spectrum when monitoring the emission at 1012 nm of the Yb 3+ ion readily suggests that an efficient energy transfer from the host to Yb 3+ occurs. As we know, most of Ce 3+ -Yb 3+ co-activated NIR phosphors give a narrow NIR emission band located at about 980 nm [17,18]. In sharp contrast, herein we observed a very broad NIR emission with FWHM of 1635 cm -1 .…”

Enhancing solar cell efficiency: the search for luminescent materials as spectral converters

“…The NIR quantum-cutting for the Ce 3+ -Yb 3+ couple has been reported for many host materials, and the cooperative ET [Ce 3+ (5d -4f); 2Yb 3+ ( 2 F 7/2 -2 F 5/2 )] appears to be the dominant relaxation route to achieve the NIR emission of Yb 3+ . [279][280][281][282][283][284]303,304 When compared to the most common Ln 3+ -Yb 3+ (Ln = Tb, Tm, and Pr) couples, the Ce 3+ -Yb 3+ couple could harvest a broad solar spectral range to give rise to intense NIR emissions. This result can be ascribed to the large absorption cross-section of Ce 3+ acting as the energy donor (Fig.…”

Extra-Broad Band Orange-Emitting Ce3+-Doped Y3Si5N9O Phosphor for Solid-State Lighting: Electronic, Crystal Structures and Luminescence Properties

“…One can see that the crystal lattice of Y 2.9 Si 5 N 9 O:Ce 0.1 expands slightly which is attributed to the larger ionic radii of Ce 3+ (1.21 Å CN=7, 1.14 Å CN=8) than that of Y 3+ (1.10Å CN=7, 1.02 Å CN=8). 38 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 …”