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1.
Volatile Eu complexes, namely Eu(TTA)3Phen, Eu(x)Y(1‐x)(TTA)3 Phen; Eu(x)Tb(1‐x)(TTA)3Phen; Eu, europium; Y, yttrium; Tb, Terbium; TTA, thenoyltrifluoroacetone; and Phen, 1,10 phenanthroline were synthesized by maintaining stichiometric ratio. Various characterization techniques such as X‐ray diffraction (XRD), photoluminescence (PL) and thermo gravimetric analysis/differential thermal analysis (TGA/DTA) were carried out for the synthesized complexes. Diffractograms of all the synthesized complexes showed well‐resolved peaks, which revealed that pure and doped organic Eu3+ complexes were crystalline in nature. Of all the synthesized complexes, Eu0.5 Tb0.5(TTA)3Phen showed maximum peak intensity, while the angle of maximum peak intensity for all complexes was almost the same with slightly different d‐values. A prominent sharp red emission line was observed at 611 nm when excited with light at 370 nm. It was observed that the intensity of red emissions increased for doped europium complexes Eu(x)Y(1‐x)(TTA)3Phen and Eu(x)Tb(1‐x)(TTA)3 Phen, when compared with Eu complexes. Emission intensity increased in the following order: Eu(TTA)3Phen > Eu0.5 Tb0.5(TTA)3Phen > Eu0.4 Tb0.6(TTA)3Phen > Eu0.5Y0.5(TTA)3Phen > Eu0.4Y0.6(TTA)3Phen, proving their potential application in organic light‐emitting diodes (OLEDs). TGA showed that Eu complexes doped in Y3+ and Tb3+ have better thermal stability than pure Eu complex. DTA analysis showed that the melting temperature of Eu(TTA)3 Phen was lower than doped Eu complexes. These measurements infer that all complexes were highly stable and could be used as emissive materials for the fabrication of OLEDs. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
2.
Israel F. Costa Gilvan P. Pires Jos Geraldo P. Espínola Hermi F. Brito Maria Claudia F.C. Felinto Wagner M. Faustino Ercules E.S. Teotonio 《Luminescence》2020,35(3):365-372
This paper reports on the preparation, characterization, and photoluminescence properties of novel hybrid materials, in which the EDTA–Ln–L complexes (where L: H2O, acac, bzac, dbm, and tta ligands, and Ln: Eu, Gd, and Tb) were covalently linked to the precursor medium molecular weight chitosan surface (CS) matrices or on the chitosan surfaces previously crosslinked with epichlorohydrin (CSech). The emission spectra of these materials were characterized by intraconfigurational‐4fN transitions centred on the Eu3+ and Tb3+ ions. Some broad bands from the polymeric matrix were also observed in the emission spectra, however the relative intensities of the intraconfigurational bands increased significantly for systems containing diketonate ligands when the antenna effect became more efficient. The values of the radiative rates (Arad) were higher for crosslinked hybrid systems with epichlorohydrin, while nonradiative rates (Anrad) presented the opposite behaviour. These data contributed to an increase in the values of emission quantum efficiency (η) for crosslinked materials. The effect of the modification process and antenna ligand on the values of intensities, intensity parameters Ω2 e Ω4 of the Eu3+ complexes were also investigated. The results showed that the crosslinked biopolymer surfaces have great potential for applications in molecular devices light converters. 相似文献
3.
Synthesis,characterization and luminescent properties of europium complexes with 2,4,6‐tris‐(2‐pyridyl)‐s‐triazine as highly efficient sensitizers
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Jie Kang Ying‐Nan Chen Ai‐Ling Wang Hai‐Yan Li Yan‐Rong Qu Hai‐Xia Zhang Hai‐Bin Chu Yong‐Liang Zhao 《Luminescence》2015,30(8):1360-1366
Using 2,4,6‐tris‐(2‐pyridyl)‐s‐triazine (TPTZ) as a neutral ligand, and p‐hydroxybenzoic acid, terephthalic acid and nitrate as anion ligands, five novel europium complexes have been synthesized. These complexes were characterized using elemental analysis, rare earth coordination titrations, UV/vis absorption spectroscopy and infrared spectroscopy. Luminescence spectra, luminescence lifetime and quantum efficiency were investigated and the mechanism discussed in depth. The results show that the complexes have excellent emission intensities, long emission lifetimes and high quantum efficiencies. The superior luminescent properties of the complexes may be because the triplet energy level of the ligands matches well with the lowest excitation state energy level of Eu3+. Moreover, changing the ratio of the ligands and metal ions leads to different luminescent properties. Among the complexes, Eu2(TPTZ)2(C8H4O4)(NO3)4(C2H5OH)·H2O shows the strongest luminescence intensity, longest emission lifetime and highest quantum efficiency. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
4.
Eu3+‐doped polystyrene and polyvinylidene fluoride nanofibers made by electrospinning for photoluminescent fabric designing
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Sangeeta Gopichandra Itankar Manjusha Prafulla Dandekar Subhash Baburao Kondawar Bhaskar Marotrao Bahirwar 《Luminescence》2017,32(8):1535-1540
Eu3+‐doped polystyrene and polyvinylidene fluoride (PVDF/Eu3+ and PS/Eu3+) nanofibers were made using electrospinning. These fibers were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT‐IR), energy dispersive spectroscopy (EDX) and photoluminescence (PL). Spectral analysis of PVDF/Eu3+ and PS/Eu3+ nanofibers was based on their emission spectra. A bright red emission was noticed from Eu3+ that was assigned to the hypersensitive 5D0 → 7F2 transition. The enhanced intensity ratios of 5D0 → 7F2 to 5D0 → 7F1 transitions in the nanofibers indicated a more polarized chemical environment for the Eu3+ ions and greater hypersensitivity for the 5D0 → 7F2 transition, which showed the potential for application in various polymer optoelectronic devices. The Eu3+‐doped polymer (PVDF/Eu3+ and PS/Eu3+) nanofibers are suitable for the photoluminescent white light fabric design of smart textiles. This paper focuses on the potential application of smart fabrics to address challenges in human life. 相似文献
5.
Aluminium oxide (Al2O3) has widely been used for catalysts, insulators, and composite materials for diverse applications. Herein, we demonstrated if γ‐Al2O3 was useful as a luminescence support material for europium (Eu) (III) activator ion. The hydrothermal method and post‐thermal treatment at 800°C were employed to synthesize Eu(III)‐doped γ‐Al2O3 nanofibre structures. Luminescence characteristics of Eu(III) ions in Al2O3 matrix were fully understood by taking 2D and 3D‐photoluminescence imaging profiles. Various sharp emissions between 580 to 720 nm were assigned to the 5D0→7FJ (J = 0, 1, 2, 3, 4) transitions of Eu(III) activators. On the basis of X‐ray diffraction crystallography, Auger elemental mapping and the asymmetry ratio, Eu(III) ions were found to be well doped into the γ‐Al2O3 matrix at a low (1 mol%) doping level. A broad emission at 460 nm was substantially increased upon higher (2 mol%) Eu(III) doping due to defect creation. The first 3D photoluminescence imaging profiles highlight detailed understanding of emission characteristics of Eu(III) ions in Al oxide‐based phosphor materials and their potential applications. 相似文献
6.
The Eu2+‐induced enhancement of defect luminescence of ZnS was studied in this work. While photoluminescence (PL) spectra exhibited 460 nm and 520 nm emissions in both ZnS and ZnS:Eu nanophosphors, different excitation characteristics were shown in their photoluminescence excitation (PLE) spectra. In ZnS nanophosphors, there was no excitation signal in the PLE spectra at the excitation wavelength λex > 337 nm (the bandgap energy 3.68 eV of ZnS); while in ZnS:Eu nanophosphors, two excitation bands appeared that were centered at 365 nm and 410 nm. Compared with ZnS nanophosphors, the 520 nm emission in the PL spectra was relatively enhanced in ZnS:Eu nanophosphors and, furthermore, in ZnS:Eu nanophosphors the 460 nm and 520 nm emissions increased more than 10 times in intensity. The reasons for these differences were analyzed. It is believed that the absorption of Eu2+ intra‐ion transition and subsequent energy transfer to sulfur vacancy, led to the relative enhancement of the 520 nm emission in ZnS:Eu nanophosphors. In addition, more importantly, Eu2+ acceptor‐bound excitons are formed in ZnS:Eu nanophosphors and their excited levels serve as the intermediate state of electronic relaxation, which decreases non‐radiative electronic relaxation and thus increases the intensity of the 460 nm and 520 nm emission dramatically. In summary, the results in this work indicate a new mechanism for the enhancement of defect luminescence of ZnS in Eu2+‐doped ZnS nanophosphors. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
7.
The luminescent properties and crystal structure of Sr(1.5‐x)‐(1.5y)Mg0.5SiO4:xEu2+,yCe3+ blue phosphor synthesized by co‐precipitation method
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In order to improve the luminescent performance of silicate blue phosphors, Sr(1.5‐x)‐(1.5y)Mg0.5SiO4:xEu2+,yCe3+ phosphors were synthesized using one‐step calcination of a precursor prepared by chemical co‐precipitation. The crystal structure and luminescent properties of the phosphors were analyzed using X‐ray diffraction and fluorescence spectrophotometry, respectively. Because the activated ions (Eu2+) can occupy two different types of sites (Sr1 and Sr2), the emission spectrum of Eu2+ excited at 350 nm contains two single bands (EM1 and EM2) in the wavelength range 400–550 nm, centered at 463 nm, and the emission intensity first increases and then decreases with increasing concentrations of Eu2+ ions. Co‐doping of Ce3+ ions can greatly enhance the emission intensity of Eu2+ by transferring its excitation energy to Eu2+. Because of concentration quenching, a higher substitution concentration of Ce3+ can lead to a decrease in the intensity. Meanwhile, the quantum efficiency of the phosphor is improved after doping with Ce3+, and a blue shift phenomenon is observed in the CIE chromaticity diagram. The results indicate that Sr(1.5‐x)‐(1.5y)Mg0.5SiO4:xEu2+,yCe3+ can be used as a potential new blue phosphor for white light‐emitting diodes. 相似文献
8.
Yttrium is stoichiometrically doped into europium by mole percentage, during the synthesis of Y(1‐x)Eu(x)(TTA)3(Phen), using solution techniques (where x = 0.2, 0.4, 0.5, 0.6 and 0.8, TTA = thenoyltrifluoroacetone and Phen = 1,10‐phenanthroline).These complexes were characterized using different techniques such as X‐ray diffraction, thermogravimetric/differential thermal analysis, optical absorption and emission spectra. Thin films of the doped Eu–Y complexes were prepared on a glass substrate under a high vacuum of 10‐6 Torr. The photoluminescence spectra of these thin films were recorded by exciting the sample at a wavelength of 360 nm. The emission peak for all the synthesized complexes centered at 611 nm; maximum emission intensity was obtained from Y0.6Eu0.4 (TTA)3(Phen). The results proved that these doped complexes are more economical than pure Eu(TTA)3(Phen) and are best suited as red emissive material for energy‐efficient and eco‐friendly organic light‐emitting diodes and displays. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
9.
An inorganic NaMgSO4F fluoride material was prepared by the wet chemical method and studied for its photoluminescence (PL) and resonant–non‐resonant energy transfer (RET and NORET) capabilities between Ce3+ → Tb3+, Ce3+ → Eu3+ and Ce3+ → Dy3+ rare earth ions. The Tb3+ emission for Ce3+ → Tb3+ transfers under ultraviolet (UV) wavelengths peaked at 491, 547, and 586 nm, for excitation at 308 nm due to 5D4 → 7FJ (J = 4, 5, 6) transitions. Eu emission spectra were observed at 440 nm (Eu2+), 593 nm and 616 nm (Eu3+) recorded for different concentrations of materials, whereas Dy3+ emission from Ce3+ → Dy3+ transfer under UV wavelengths peaked at 485 nm and 577 nm due to 4F9/2 → 6H15/2 and 6H13/2 transitions. The purpose of the present study is to understand the RET and NORET effects of Tb3+, Eu3+ and Dy3+ co‐doping in a NaMgSO4F:Ce3+ luminescent material, which could be used as a green‐emitting material for lamp phosphors. 相似文献
10.
Mantwa Annah Lephoto Kamohelo George Tshabalala Selepe Joel Motloung Samy Khalil Kamel Shaat Odireleng Martin Ntwaeaborwa 《Luminescence》2017,32(6):1084-1091
Europium (Eu3+) and bismuth (Bi3+) co‐activated LiBaBO3 powder phosphors were synthesized by a solid‐state reaction and the structure, particle morphology, optical and photoluminescent properties were investigated. X‐Ray diffraction patterns of the LiBaBO3 phosphors crystallized in a pure monoclinic phase, i.e. there were no secondary phases due to either incidental impurities or undecomposed starting materials. Scanning electron microscopy images showed that the powders were made up of fluffy needle‐like particles that were randomly aligned. The band‐gap of the LiBaBO3 host was estimated to be 3.33 eV from the UV/vis absorption data. Blue emission was observed from the LiBaBO3 host, which is ascribed to self‐activation of the host matrix. In addition, greenish‐blue (493 nm) and red (613 nm) emissions were observed from europium‐doped samples and were attributed to the emissions of Eu2+ and Eu3+, respectively. Furthermore, after codoping with Bi3+, the emission intensity of Eu3+ located at 613 nm was significantly enhanced. From the Commission Internationale de I′Eclairage (CIE) color coordinates, white emission was observed from LiBa1–xBO3:xEu3+ (x = 0.020 and 0.025) phosphor powders with color coordinates of x = 0.368, y = 0.378 and x = 0.376, y = 0.366, respectively. 相似文献
11.
Rare‐earth ions play an important role in eco‐friendly solid‐state lighting for the lighting industry. In the present study we were interested in Eu3+ ion‐doped inorganic phosphors for near ultraviolet (UV) excited light‐emitting diode (LED) applications. Eu3+ ion‐activated SrYAl3O7 phosphors were prepared using a solution combustion route at 550°C. Photoluminescence characterization of SrYAl3O7:Eu3+ phosphors showed a 612 nm emission peak in the red region of the spectrum due to the 5D0→7F2 transition of Eu3+ ions under excitation at 395 nm in the near‐UV region and at the 466 nm blue excitation wavelength. These red and blue emissions are supported for white light generation for LED lighting. Structure, bonding between each element of the sample and morphology of the sample were analysed using X‐ray diffraction (XRD) and scanning electron microscopy (SEM), which showed that the samples were crystallized in a well known structure. The phosphor was irradiated with a 60Co‐γ (gamma) source at a dose rate of 7.2 kGy/h. Thermoluminescence (TL) studies of these Eu3+‐doped SrYAl3O7 phosphors were performed using a Nucleonix TL 1009I TL reader. Trapping parameters of this phosphor such as activation energy (E), order of kinetics (b) and frequency factor (s) were calculated using Chen's peak shape method, the initial rise method and Ilich's method. 相似文献
12.
The Eu2+/Eu3+ mixed valence phosphor Ca2SiO2F2:Eu2+/Eu3+ was prepared using a solid‐state reaction synthesis method in a CO atmosphere, and the optical properties were investigated. The spectroscopic properties revealed that Ca2+ ions were occupied by both Eu2+ and Eu3+ ions in Ca2SiO2F2, and both ions were able to generate their characteristic emissions. A broad 5d → 4f Eu2+ band at ~470 nm and narrow 4f → 4f Eu3+ peaks upon excitation with n‐UV light were observed. The ratio between Eu2+ and Eu3+ emissions changed regularly, and the relative intensity of the red component from Eu3+ became systematically stronger with increasing overall Eu content. As a result, the emission color of these phosphors can be tunable from blue to pink under n‐UV light excitation. 相似文献
13.
Spectral investigations on Eu3+,Sm3+‐doped and Sm3+/Eu3+ co‐doped potassium‐fluoro‐phosphate glass emitting intense orange‐red for lighting applications
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Kapuluri Anil Kumar Singarapu Babu Vasanthapalli Reddy Prasad Samadam Damodaraiah Yadala Chenchu Ratnakaram 《Luminescence》2017,32(8):1456-1465
Potassium fluoro‐phosphate (KFP) glass singly doped with different concentrations of europium (Eu3+) or samarium (Sm3+) or co‐doped (Sm3+/Eu3+) was prepared, and their luminescence spectra were investigated. The phase composition of the product was verified by X‐ray diffraction analysis. Optical transition properties of Eu3+ in the studied potassium phosphate glass were evaluated in the framework of the Judd–Ofelt theory. The radiative transition rates (AR), fluorescence branching ratios (β), stimulated emission cross‐sections (σe) and lifetimes (τexp) for certain transitions or levels were evaluated. Red emission of Eu3+ was exhibited mainly by the 5D0→7F2 transition located at 612 nm. Concentration quenching and energy transfer were observed from fluorescence spectra and decay curves, respectively. It was found that the lifetimes of the 5D0 level increased with increase in concentration and then decreased. By co‐doping with Sm3+, energy transfer from Sm3+ to Eu3+ occurred and contributed to the enhancement in emission intensity. Intense orange‐red light emission was obtained upon sensitizing with Sm3+ in KFP glass. This approach shows significant promise for use in reddish‐orange lighting applications. The optimized properties of the Sm3+/Eu3+ co‐doped potassium phosphate glass might be promising for optical materials. 相似文献
14.
Enhanced luminescence and white light emission from Eu3+‐co‐doped K3Ca2(SO4)3Cl:Dy3+ phosphor with near visible ultraviolet excitation for white LEDs
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The luminescent properties of europium (Eu)‐ and dysprosium (Dy)‐co‐doped K3Ca2(SO4)3Cl halosulfate phosphors were analyzed. This paper reports the photoluminescence (PL) properties of K3Ca2(SO4)3Cl microphosphor doped with Eu and Dy and synthesized using a cost‐effective wet chemical method. The phosphors were characterized by X‐ray diffraction and scanning electron microscopy. The CIE coordinates were calculated to display the color of the phosphor. PL emission of the prepared samples show peaks at 484 nm (blue), 575 nm (yellow), 594 nm (orange) and 617 nm (red). The emission color of the Eu,Dy‐co‐doped K3Ca2(SO4)3Cl halophosphor depends on the doping concentration and excitation wavelength. The addition of Eu in K3Ca2(SO4)3Cl:Dy greatly enhances the intensity of the blue and yellow peaks, which corresponds to the 4 F9/2 → 6H15/2 and 4 F9/2 → 6H13/2 transitions of Dy3+ ions (under 351 nm excitation). The Eu3+/Dy3+ co‐doping also produces white light emission for 1 mol% of Eu3+, 1 mol% of Dy3+ in the K3Ca2(SO4)3Cl lattice under 396 nm excitation, for which the calculated chromaticity coordinates are (0.35, 0.31). Thus, K3Ca2(SO4)3Cl co‐doped with Eu/Dy is a suitable candidate for NUV based white light‐emitting phosphors technology. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
15.
In this article Ca1‐xTiO3:xEu3+ single crystalline particles with a cubic morphology and average size of 248 to 815 nm were synthesized by a solvothermal method. The structural and optical properties of the Ca1‐xTiO3:xEu3+ cubes were investigated, the formation mechanism of the cubes were analyzed and discussed, and the influence of Eu doping content and cubic size on the photoluminescence were examined. The differences in the photoluminescence between Ca1‐xTiO3:xEu3+ cubic crystals and nanoparticles was analyzed. It was found that an addition of a small amount of water can substantially reduce the size of the cubes. An obvious red emission band centered at 615 nm was observed under the excitation at 395 nm for the cubes. Our results demonstrate CaTiO3 cubes are good host materials for designing red phosphors. 相似文献
16.
Zinc stannate (Zn2SnO4) and Zn2SnO4 codoped with Eu3+ and Ca2+ (ZTO:Eu,Ca) were synthesized by hydrothermal method and characterized with X‐ray diffraction (XRD), energy‐dispersive X‐ray analysis (EDAX), Raman spectrometer, field emission scanning electron microscopy (FESEM), ultraviolet‐visible (UV‐vis) and photoluminescence (PL) spectrophotometers. PL analysis of Zn2SnO4 gives broad defect induced emission in the region 500–750 nm. The crystal structure of Zn2SnO4 was retained even with a nominal doping of Eu, Ca and its combination in the Zn2SnO4. The Eu3+ ions were found to occupy the non‐centrosymmetric sites of the Zn2SnO4 and gave emissions at 592, 615 and 702 nm. Zn2SnO4:Eu,Ca showed red emission at 615 nm attributed to the electronic transition from the excited state 5D0 → 7F2 of the 4f6 configuration of Eu3+. Nominal codoping of Eu3+ and Ca2+ ions promoted the quenching of orange emission from Eu3+ in Zn2SnO4:Eu,Ca. 相似文献
17.
Photoluminescence properties of LiBaPO4:M3+ phosphor for near‐UV light‐emitting diode (M = Eu and Dy)
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A novel phosphor LiBaPO4 doped with rare earths Eu and Dy prepared by high temperature solid‐state reaction method is reported. The phosphors were characterized by X‐ray powder diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL). The emission and excitation spectra of these materials were measured at room temperature with a spectrofluorophotometer. The excitation spectra of LiBaPO4:Eu3+ phosphor can be efficiently excited by 394 nm, which is matched well with the emission wavelength of near‐UV light‐emitting diode (LED) chip. PL properties of Eu3+‐doped LiBaPO4 exhibited the characteristic red emission coming from 5D0 → 7 F1 (593 nm) and 5D0 → 7 F2 (617 nm) electronic transitions with color co‐ordinations of (0.680, 0.315). The results demonstrated that LiBaPO4:Eu3+ is a potential red‐emitting phosphor for near‐UV LEDs. Emission spectra of LiBaPO4:Dy3+ phosphors showed efficient blue (481 nm) and yellow (574 nm) bands, which originated from 4 F9/2 → 6H15/2 and 4 F9/2 → 6H13/2 transitions of the Dy3+ ion, respectively. The 574 nm line is more intense than the 481 nm lines, which indicates that the site Dy3+ is located with low symmetry. This article summarizes fundamentals and possible applications of optically useful inorganic phosphates with visible photoluminescence of Eu3+ and Dy3+ ions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
18.
Ísis F. Manali Lucas C.V. Rodrigues Adriano H. Braga Douglas Galante Vernica C. Teixeira 《Luminescence》2020,35(4):456-465
Luminescent nanoparticles of Y2O3 doped with europium (Eu) and/or titanium (Ti) were synthesized using modified sol–gel routes. The crystalline cubic phase was confirmed using X‐ray powder diffraction (XRD). Particle morphology and size were evaluated using scanning and transmission electron microscopy. High‐resolution transmission electron microscopy showed that the synthesis method affected the average particle size and the Fourier transform of the images showed the lattice plane distances, indicating that the samples presented high crystallinity degree in accordance with the XRD pattern. The Ti valence was investigated using X‐ray absorption near edge spectroscopy and the tetravalent form was the dominant oxidizing state in the samples, mainly in Eu and Ti co‐doped Y2O3. Optical behaviour was investigated through X‐ray excited optical luminescence and photoluminescence under ultraviolet–visible (UV–vis) and vacuum ultraviolet (VUV) excitation. Results indicated that Eu3+ is the emitting centre in samples doped with only Eu and with both Eu and Ti with the 5D0→7F2 transition as the most intense, indicating Eu3+ in a noncentrosymmetric site. Finally, in the Eu,Ti‐doped Y2O3 system, Ti3+ (or TiIV) excitation was observed but no Ti emission was present, indicating a very efficient energy transfer process from Ti to Eu3+. These results can aid the development of efficient nanomaterials, activated using UV, VUV, or X‐rays. 相似文献
19.
Zhenyu Gao Lixin Yu Xiaoqin Man Jianlin Zhong Qihuang Guo Yingxuan Zou 《Luminescence》2019,34(8):830-837
The MgO–Ga2O3–SiO2 glasses and glass‐ceramics samples doped with Eu2+/Mn2+/Er3+ and heated in reductive atmosphere were prepared by the sol–gel method. The structure, morphology and the luminescence properties were studied using X‐ray diffraction, high‐resolution transmission electron microscope, fluorescence spectra, and up‐conversion emission. The luminescence characteristics of doped ions could be influenced by temperature and matrix component. The characteristic emission of Mn2+, Eu2+ and Er3+ were seen and the energy transfer efficiency from Eu2+ to Mn2+ was enhanced as Mn2+ concentration was increased. In addition, the two‐photon process was determined for the Er3+‐doped samples. 相似文献
20.
A series of Eu3+‐activated NaLi2PO4 novel phosphors was synthesized by the solid‐state reaction method. The X‐ray diffraction (XRD) and photoluminescence (PL) properties of these phosphors were investigated at room temperature. The excitation spectra indicate that these phosphors can be effectively excited by near‐UV (370–410 nm) light. The emission spectra exhibit strong reddish‐orange performance, which is due to the 5D0 → 7FJ transitions of Eu3+ ions. The orange emission from transition 5D0 → 7F1 is dominant over that of 5D0 → 7F2. The concentration quenching of Eu3+ was observed in NaLi2PO4:Eu3+ when the Eu concentration was at 1 mol%. The impact of doping Eu3+ and photoluminescence properties were investigated and we propose a feasible interpretation. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献