Spectroscopic properties of red emitting Eu3+ doped Y2SiO5 nanophosphors for WLED׳s on the basis of Judd–Ofelt analysis: Calotropis gigantea latex mediated synthesis

Crystal Growth & Design

et al. 2017

This article reports the flux composition optimization, crystal growth, and optical spectroscopic properties of LaBSiO 5 and Eu 3+ -substituted LaBSiO 5 crystals. The mixture design technology was successfully applied in the crystal growth area for the first time. By the direction of mixture design method, the composition of a complex flux comprising LaBO 3 , SiO 2 , and Li 2 MoO 4 was optimized and used for growth of LaBSiO 5 crystals. A large size of Eu 3+ -substituted LaBSiO 5 crystal with dimension of 12 × 10 × 8 mm 3 has been prepared by top-seeded solution growth method. As far as we know, it is the first report that active ionsubstituted LaBSiO 5 bulk crystal was obtained from an environmentally friendly flux without fluorides. The optical spectroscopy and electronic transition properties of Eu 3+ -substituted LaBSiO 5 crystals are studied thoroughly by analyzing the excitation and emission spectra and luminescence decay curves. The luminescence of Eu 3+ ions are characteristic of intense red light emission corresponding to transitions of 5 D 0 → 7 F 1 and 5 D 0 → 7 F 2 . Meanwhile, the splitting of emission bands mentioned above is apparent because of the lower symmetry of lattice sites where the active ion locates. Furthermore, the symmetry properties of the lattice sites where Eu 3+ ions locate are investigated by using Judd−Ofelt theory. The value of intensity parameters of Eu 3+ -substituted LaBSiO 5 ranges from 4.19 to 4.89 when the Eu 3+ concentration varies.

Section: Resultsmentioning

confidence: 85%

Flux Exploration, Growth, and Optical Spectroscopic Properties of Large Size LaBSiO₅ and Eu³⁺-Substituted LaBSiO₅ Crystals

Lin

Crystal Growth & Design

et al. 2017

“…The intensity of the 5 D 0 → 7 F 1 transition was independent of the host matrix whereas that of the 5 D 0 → 7 F J ( J = 2, 4) transition depends solely on the parameters of Judd–Ofelt (J–O) theory. 21 Thus, the emission intensity ratios increase at elevated temperatures, suggesting that the J–O parameters become larger with increasing temperature. For the forced 4f–4f transitions of rare-earth ions, the relationship between the cross-section for the i → j transition and the J–O parameters is shown as follows: 22 where Ω t ( t = 2, 4, 6) is the J–O parameter, and U ( t ) ( t = 2, 4, 6) denotes the reduced matrix elements for the i → j transition.…”

Section: Resultsmentioning

confidence: 96%

Excitation-wavelength-dependent anti-thermal quenching of upconversion luminescence in hexagonal NaGdF₄:Nd³⁺/Yb³⁺/Er³⁺ nanocrystals

Pang

et al. 2022

J. Mater. Chem. C

“…41-0004. 32 Under excitation by a 450 nm laser, both the YSO-Pr powder and YSO-Pr/PVA/SA film exhibited upconversion luminescence with their emission spectra, mainly concentrated around 380 nm (Fig. 4).…”

Section: Properties Of Yso-pr/pva/samentioning

confidence: 99%

Visible-UVC upconversion polymer films for prevention of microbial infection

Zhao

et al. 2023

J. Mater. Chem. B