Synthesis and luminescent properties of nanocrystalline CaYAlO₄:Sm³⁺ phosphors

Abstract

Nanocrystalline CaYAlO4:Sm3+ phosphors were synthesized by a citrate‐based sol–gel method. After annealing at 1000 °C, the closely packed particles with pure tetragonal crystalline structure were observed. The photoluminescence spectra exhibited the emission peaks of 565 nm (4G5/2 → 6H5/2), 600 nm (4G5/2 → 6H7/2), and 650 nm (4G5/2 → 6H9/2) under an excitation wavelength of 409 nm. The optimum concentration of CaYAlO4:Sm3+ phosphors was found to be 2 mol%. The lifetimes were measured to analyze the effect of Sm3+ concentration in CaYAlO4 host lattice. And similar emissions of cathode‐luminescence (CL) spectra were also observed. By increasing the accelerating voltage from 1 to 5 kV, the CL intensity was linearly increased.

Histone acetylation and methylation marks in chromatin of Panstrongylus megistus (Hemiptera, Reduviidae)

“…To confirm and quantify the presence of these secondary phases, Rietveld refinement was carried out in three samples, which are representative of the behavior of the system in study: CaYAlO 4 doped with 1, 5 and 10 mol% of Eu 3þ heat-treated at 1100 C. The values of the parameters cells and volume of major phase are presented in Table 2. The results show good agreement with other values reported in the literature and standard ICSD 72104 (CaYAlO 4 ) [18,20]. It is possible to observe the increasing in the values of lattice parameters and of the volume, when the concentration of Eu 3þ in the host changes from 1 to 5 mol%.…”

Photoluminescence properties, crystal structure and electronic structure of a Sr2CaWO6:Sm3+ red phosphor

“…21,22 The trivalent Sm 3+ (4f 5 ) ion is a common activator which has been used in many kinds of host compounds for red phosphors. [23][24][25][26] The Sm 3+ ion has narrow excitation bands in the near-UV and blue region and emission bands in the reddish-orange light region, due to intrinsic 4f-4f transitions. 23,25 In this paper, SCWO:2%Sm 3+ and SCWO:2%Sm 3+ , 2%M + (M ¼ Li, Na and K) were synthesized by solid-state reactions.…”

“…[23][24][25][26] The Sm 3+ ion has narrow excitation bands in the near-UV and blue region and emission bands in the reddish-orange light region, due to intrinsic 4f-4f transitions. 23,25 In this paper, SCWO:2%Sm 3+ and SCWO:2%Sm 3+ , 2%M + (M ¼ Li, Na and K) were synthesized by solid-state reactions. The crystal structure analysis and renement of SCWO were carried out based on XRD patterns.…”

Luminescence properties and determination of optimal RE3+(Sm3+, Tb3+and Dy3+) doping levels in the KYP2O7host lattice obtained by combustion synthesis

“…The spectrum was recorded with restriction to only 4f-4f lines (direct excitation) therefore the position of the charge transfer transition (CT), normally expected in the UV region, was beyond the scope in all cases. Typical sharp lines ascribed to the transitions of 6 H 5/2 -4 H 9/2 at 347 nm (28 818 cm À1 ), 6 H 5/2 -4 D 5/2 at 365 nm (27 397 cm À1 ), 6 H 5/2 -6 P 7/2 at 377 nm (26 525 cm À1 ), 6 H 5/2 -4 F 7/2 at 404 nm (24 752 cm À1 ), 6 H 5/2 -6 P 5/2 at 420 nm (23 809 cm À1 ), 6 H 5/2 -4 G 9/2 at 443 nm (22 573 cm À1 ), 6 H 5/2 -4 I 13/2 at 468 nm (21 367 cm À1 ), 6 H 5/2 -4 I 11/2 at 484 nm (20 661 cm À1 ), 6 H 5/2 -4 G 7/2 at 503 nm (19 880 cm À1 ) and 6 H 5/2 -4 F 3/2 at 531 nm (18 832 cm À1 ), [11][12][13][14] were recorded. Fig.…”