Ce3+ to Mn2+ energy transfer in Sr3Y2Ge3O12:Ce3+, Mn2+ garnet phosphor

Unraveling the Mechanisms of Thermal Quenching of Luminescence in Ce3+-Doped Garnet Phosphors

“…This very low internal stability of luminescence is attributed to a predominant thermal ionization due to a significantly smaller Δ E i (0.45 eV) compared to those of other garnets. In comparison, SYG co-doped with Ce 3+ and Mn 2+ exhibits a quite monotonous decrease in the integrated intensity of the emission [here comprising both green (≈530 nm) emission from the Ce 3+ ions and orange (≈630 nm) emission from the Mn 2+ ions] as a function of increasing temperature . Importantly, the intensity ratio of the emission from the Ce 3+ and Mn 2+ ions remains virtually constant in the investigated temperature range (41–500 K), which indicates that any plausible energy transfer processes from the Ce 3+ to the Mn 2+ ions are virtually independent of temperature and hence have no significant effects on the thermal quenching of the Ce 3+ luminescence in this material.…”

“…Various combinations of the A, B, and C cations are possible, and these may be classified as follows: (I) substitution of the A cation, e.g., (Y, Tb, Gd, Lu) 3 Al 5 O 12 , − (II) substitution of the B and/or C cations, e.g., (Y, Gd) 3 Al 5– x Ga x O 12 , − Y 3 Sc 2 Al 3– x Ga x O 12 , , and (Y, Lu) 3 Al 5–2 x Mg x Si x O 12 , − and (III) substitution of the A (trivalent and/or divalent states), B, and C cations, e.g., (Ca, Sr) 3 (Y, Lu, Sc) 2 (Si, Ge) 3 O 12 ,− and (Y, Lu) 3– x Ca x Al 5– x Si x O 12 . , Upon Ce 3+ substitution, the Ce 3+ ion takes the place of the A site cation in most cases, due to the similar ionic sizes and charge states of the A cation and Ce 3+ . Accordingly, the local environment around Ce 3+ in the garnet structure can be described as a CeO 8 moiety.…”

Optical Signals for Quantitative and Qualitative Monitoring of Temperature‐Sensitive Products

“…Compared with the PL spectra of the SYGO host, the emission spectra of SYGO: Mn 2+ phosphors exhibit two extra broadbands, peaked at 560 and 635 nm, which are attributed to the 4 T 1 → 6 A 1 transition of Mn. 2+[ 28 ] Additionally, the emission intensity of the SYGO host at 725 nm gradually decreases with the increased Mn 2+ concentration, due to the competitive transition between the SYGO host and Mn 2+ ions. The asymmetric PL spectrum of the representative sample SYGO: 0.01Mn 2+ is Gaussian fitted into three bands of 555, 635, and 725 nm (Figure 2c), respectively.…”

Ba3LuGa2O7.5:Bi3+ phosphors with potential application in full-spectrum WLEDs and temperature sensing

“…17,18 The reason that rare Ce 3+ and Eu 2+ earth ions occupy a dominant position in commercialized activators can be ascribed to their spinallowed electron transitions allowing high bright emission light. [19][20][21] However, the emission spectra of the Eu 2+ doped phosphors are not broad enough to well cover the cyan gap. 22 In addition, a severe visible light reabsorption phenomenon is usually unavoidable in Eu 2+ and Ce 3+ doped phosphors.…”