Journal articles: 'Phosphors – Spectra'

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Tang, An, Tao Ma, Liduo Gu, Yongtao Zhao, Junhui Zhang, Haoming Zhang, Fengxiang Shao, and Hongsong Zhang. "Luminescence properties of novel red-emitting phosphor InNb1-xPxO4:Eu3+ for white light emitting-diodes." Materials Science-Poland 33, no. 2 (June 1, 2015): 331–34. http://dx.doi.org/10.1515/msp-2015-0050.

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AbstractInNb1-xPxO4:Eu3+ red phosphors were synthesized by solid-state reaction and their luminescence properties were also studied through photoluminescence spectra. The excitation and emission spectra make it clear that the as-prepared phosphors can be effectively excited by near-ultraviolet (UV) 394 nm light and blue 466 nm light to emit strong red light located at 612 nm, due to the Eu3+ transition of 5D0 → 7F2. The luminescence intensity is dependent on phosphorus content, and it achieves the maximum at x = 0.4. Excessive phosphorus in the phosphors can result in reduction of luminescence intensity owing to concentration quenching.With the increasing content of phosphorus, the phosphors are prone to emit pure red light. This shows that the InNb1.6P0.4O4:0.04Eu3+ phosphor may be a potential candidate as a red component for white light emitting-diodes.

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Qin, Haiming, Jun Jiang, Zhaohua Luo, and Haochuan Jiang. "YAG phosphor with spatially separated luminescence centers." Journal of Materials Chemistry C 4, no. 2 (2016): 244–47. http://dx.doi.org/10.1039/c5tc03151f.

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Baig, Nahida, N. S. Dhoble, N. S. Kokode, and S. J. Dhoble. "Photoluminescence Properties of Eu3+ and Ce3+ Activated Calcium Chlorophosphate Via Combustion Synthesis Method." Oriental Journal of Physical Sciences 1, no. 1-2 (August 24, 2016): 10–15. http://dx.doi.org/10.13005/ojps01.0102.03.

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Calcium chlorophosphate (Ca2PO4Cl) phosphors, activated by rare earth ions Eu3+ and Ce3+ were prepared by urea assisted combustion synthesis technique and their characterization and luminescent properties were studied. The synthesized phosphors were investigated by powdered XRD, SEM and Photoluminescence characterization (PL) methods. PL excitation spectra of Ca2PO4Cl:Eu3+/Ce3+ phosphor exhibit narrow bands in the near ultra violet (n-UV) range, and the PL emission spectra of Ca2PO4Cl: Eu3+/Ce3+ phosphor shows sharp narrow bands typical of rare earth ions. The bands observed in the PL emission and excitation spectra of Ca2PO4Cl: Eu3+/Ce3+ phosphors can be ascribed to the electronic transitions within 4f configurations of rare earth ions. The excitation peaks for Ca2PO4Cl: Eu3+ is in n-UV range. The obtained results suggest that these phosphors may be favorable for lamp industry.

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Liu, Sheng, Bei Ying Zhou, Shi Jia Gu, Lian Jun Wang, Wan Jiang, and Wei Luo. "A Promising Energy-Saving and Environmental-Friendly Lighting Device: High CRI White LED with Phosphor Materials." Materials Science Forum 848 (March 2016): 446–53. http://dx.doi.org/10.4028/www.scientific.net/msf.848.446.

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Two kinds of commercial LED phosphors (green phosphor LuAG:Ce3+ and red phosphor CaAlSiN3:Eu2+) with polymethyl methacrylate (PMMA) powders were mixed to prepare film phosphors with tunable emission peak in photoluminescence spectrum by flat vulcanizing machine under the temperature of 170 oC and pressure of 2 MPa. The physical phase, surface morphology, transmittance, luminescence spectra of samples were characterized by means of X-ray diffraction (XRD), Environmental scanning electron microscopy (ESEM), Ultraviolet-Visible (UV-Vis) spectrophotometry and Fluorescence spectrometer. The results show that the film phosphors phase was consistent with raw phosphors, phosphor particles were uniformly distributed, and fluorescence spectra with different proportions of phosphors in different position can be adjusted. Tested by HSP 3000 spectrum analyzer, the white LEDs fabricated by blue chip and composite film phosphor containing 5 wt% green phosphor and 1.5 wt.% red phosphor, which refers to the remote excitation technique, possessed color coordinate of (0.3715, 0.3280) and color rendering index (CRI) of 87 when it was driven at power of 36 V/140 mA, reaching the international advanced level.

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He, Da Wei, Yan Ning Shi, Tao Hou, and Dan Zhou. "Luminescence Properties of M₂MgSi₂O₇: Re (M = Ba, Sr, Ca) (Re = Eu²⁺, Ce³⁺, Tb³⁺)." Key Engineering Materials 336-338 (April 2007): 622–24. http://dx.doi.org/10.4028/www.scientific.net/kem.336-338.622.

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A series of phosphors of M2MgSi2O7: Eu2+ (M=Ba,Sr,Ca) have been synthesized and studied. The excitation spectra measurement showed that the phosphors had absorption in long UV light, the excitation spectra of the phosphors consisted of two broad bands: one in the range from 280nm to 330 nm and the other from 360nm to 420 nm. The main excitation band centered at around 395nm was belong to 4f→5d transitions of Eu2+. Analysis of the spectra of Ce3+ and Tb3+ co-doped phosphor showed that energy transfer from Ce3+ to Tb3+ in Ba2MgSi2O7 under UV excitation was efficient.

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Jia, Lin Yan, Zhong Bao Shao, and Jun Feng Han. "Luminescence Properties of ZnO:Eu³⁺ Red Emitting Phosphor Prepared by Precipitation Method." Advanced Materials Research 690-693 (May 2013): 594–97. http://dx.doi.org/10.4028/www.scientific.net/amr.690-693.594.

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Zinc oxide doped with Eu3+ ions red emitting phosphors were prepared by precipitation method, and its luminescence properties were investigated. The phosphors were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL) spectra. The ZnO:Eu3+ phosphors were obtained at 600°C by calcining precipitation precursor. These phosphors can be effectively excited at 465nm. In emission spectra, the strongest peak at 616nm correlating to red emission is due to the electric dipole transition 5D07F2 of Eu3+ ions. Eu3+ions replaced Zn2+ ions and occupied the non-centrosymmetric sites in the ZnO matrix lattice. The phosphor particles with narrow distribution range are approximately 100-200nm in size. The luminescence properties of ZnO:Eu3+ phosphor with 8 mol% doping concentration of Eu3+ is optimal.

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Lisitsyn, Lisitsyna, Tulegenova, Ju, Polisadova, Lipatov, and Vaganov. "Nanodefects in YAG:Ce-Based Phosphor Microcrystals." Crystals 9, no. 9 (September 11, 2019): 476. http://dx.doi.org/10.3390/cryst9090476.

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The present paper focused on the study of spectral–kinetic characteristics of luminescence in two batches of yttrium aluminum garnet (YAG):Ce-based phosphors synthesized in different years by two manufacturers: NPO “Platan” in Russia and “GrandLux” in the People’s Republic of China (PRC). Upon studying the structural characteristics of the phosphors—elemental composition, morphology, and X-ray diffraction (XRD) patterns—it was concluded that both types of YAG:Ce phosphors are highly imperfect. The presence of heterogeneities of different nature was accompanied by the introduction—to compensate for charges and elastic stresses—of intrinsic lattice defects during synthesis. There is a high probability of creating complex defects during phosphor synthesis. Luminescence properties (full width at half maximum (FWHM), spectral position of the emission peaks, excitation spectra of emission, emission decay time) are affected by the nearest environment of the luminescence center; whereas the degree of correlation of defects (distance between the components of the donor–acceptor pair) does not depend on the concentration of impurities, intrinsic defects, and their ratio. The results do not fit into the framework of existing ideas regarding the processes in phosphors as systems with widely distributed luminescence centers. The patterns obtained in the paper are discussed based on a hypothesis according to which a nanodefect phosphorus crystal phase is formed during the synthesis.

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MURALEEDHARAN, R., M. S. K. KHOKHAR, V. P. NAMBOODIRI, and C. P. GIRIJAVALLABHAN. "N2 LASER INDUCED PHOTOLUMINESCENCE EMISSION IN (ZnS: ZnO):Cu PHOSPHORS." Modern Physics Letters B 10, no. 18 (August 10, 1996): 883–89. http://dx.doi.org/10.1142/s0217984996001000.

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Nitrogen laser induced photoluminescence (PL) emissions from (ZnS: ZnO):Cu powder phosphors have been carried out under varying conditions of sample preparation. The conditions for optimum efficiency of PL emission in (ZnS: ZnO):Cu phosphors and their spectral characteristics have been investigated. The emission peak in the PL spectra was found to shift towards longer wavelengths side as the concentrations of ZnO in (ZnS: ZnO) mixture was varied from 0% to 100%. The mechanism of PL emission in the above phosphor is explained on the basis of classical “Schon-Klassen” model.

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Lu, Hao-Ying, and Meng-Han Tsai. "The High-Temperature Synthesis of the Nanoscaled White-Light Phosphors Applied in the White-Light LEDs." Advances in Materials Science and Engineering 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/976106.

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The white-light phosphors consisting of Dy3+doped YPO4and Dy3+doped YP1-XVXO4were prepared by the chemical coprecipitation method. After the 1200°C thermal treatment in the air atmosphere, the white-light phosphors with particle sizes around 90 nm can be obtained. In order to reduce the average particle size of phosphors, the alkaline washing method was applied to the original synthesis process, which reduces the particle sizes to 65 nm. From the PLE spectra, four absorption peaks locating at 325, 352, 366, and 390 nm can be observed in the YPO4-based phosphors. These peaks appear due to the following electron transitions:6H15/2→4K15/2,6H15/2→4M15/2+6P7/2,6H15/2→4I11/2, and6H15/2→4M19/2. Besides, the emission peaks of wavelengths 484 nm and 576 nm can be observed in the PL spectra. In order to obtain the white-light phosphors, the vanadium ions were applied to substitute the phosphorus ions to compose the YP1-XVXO4phosphors. From the PL spectra, the strongest PL intensity can be obtained with 30% vanadium ions. As the concentration of vanadium ions increases to 40%, the phosphors with the CIE coordinates locating at the white-light area can be obtained.

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Wang, Jun-Feng, Hao Zu, Chuan-Wen Lin, Shou-Jun Ding, Peng-Yu Shao, and Ye Xia. "Synthesis and Luminescence Properties of SrGd2O4:Eu3+ Red Phosphors." International Journal of Optics 2020 (April 14, 2020): 1–5. http://dx.doi.org/10.1155/2020/3095429.

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As one of the important raw materials for LED products, phosphors play an important role. At present, the spectrum of LED phosphors lacks red light, resulting in poor quality of white LED products and a low color rendering index (Ra <80), which affects lighting effects. To solve this problem, we synthesized the SrGd2O4:Eu3+ red phosphor by a high-temperature solid-phase method. The structure and luminescence properties of SrGd2O4:Eu3+ red phosphors were studied by means of X-ray diffraction (XRD) measurements of their emission and excitation spectra, and their spectra were analyzed. We also studied the Eu3+ doping concentration with the best luminous efficiency and the color coordinate of the SrGd2O4:Eu3+ phosphor. The experimental results show that SrGd2O4:Eu3+ is a new red phosphor material that can be used for near-ultraviolet or blue-light excitation and has good practicability.

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11

Pang, Maolin, Xiaoming Liu, and Jun Lin. "Luminescence properties of R2MoO6:Eu3+ (R = Gd, Y, La) phosphors prepared by Pechini sol-gel process." Journal of Materials Research 20, no. 10 (October 2005): 2676–81. http://dx.doi.org/10.1557/jmr.2005.0356.

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R2MoO6:Eu3+ (R = Gd, Y, La) phosphors were prepared by the Pechini sol-gel process. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), reflectance spectra, photoluminescence (PL) spectra, and lifetimes were used to characterize the resulting phosphors. The results of XRD indicate that all of the R1.96Eu0.04MoO6 (R = Gd, Y, La) phosphors crystallized completely at 800 °C. Y1.96Eu0.04MoO6 and Gd1.96Eu0.04MoO6 are of isomorphous monoclinic (α) structure, while La1.96Eu0.04MoO6 preferentially adopts the tetragonal (γ) form. FE-SEM study reveals that the samples mainly consist of aggregated particles with an average grain size ranging from 100 to 250 nm. The luminescent properties of R2MoO6:Eu3+ (R = Gd, Y, La) phosphors are largely dependent on their structure, grain size, and powder morphology. The isomorphous Y2MoO6:Eu3+ and Gd2MoO6:Eu3+ phosphors show very similar luminescence properties, which differ greatly from that of the La2MoO6:Eu3+ phosphor.

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Zhang, Ji Ming, Dong Lin Zhao, and Zeng Min Shen. "Synthesis and Luminescent Properties of Mn²⁺-Doped Zinc Silicate Phosphors by Sol-Gel Method." Key Engineering Materials 434-435 (March 2010): 214–16. http://dx.doi.org/10.4028/www.scientific.net/kem.434-435.214.

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Abstract. Green light emitting Mn2+-doped Zn2SiO4 (Zn2SiO4:Mn2+) phosphor nano-particles were synthesized by sol-gel method combined with a furnace firing from the sol-gel solution made with ZnO, MnCO3 and tetraethoxysilan. The influences of annealing temperatures on the microstructures and photoluminescent properties of the Zn2SiO4:Mn2+ phosphors were investigated. The structural details of the phosphors were examined through XRD and SEM. The photoluminescent properties of the Zn2SiO4:Mn2+ phosphors were characterized by excitation and emission spectra. The results indicate that the XRD patterns of the Zn2SiO4:Mn2+ phosphors exhibit a willemite structure (-Zn2SiO4). Green photoluminescence whose emission peak is located at 525 nm were observed from the synthesized phosphor particles under UV excitation. The photoluminescent mechanisms of the Zn2SiO4:Mn2+ phosphors were discussed.

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13

Zhang, Dandan, Huaxing Xiao, Wei Jiang, Xia Cao, Lu Huang, Gang Liu, Manyu Ye, and Zhiwei Zhang. "Enhancement of the red emission in Ba3(PO4)2:Eu3+ by addition of charge compensator Na+." Modern Physics Letters B 32, no. 34n36 (December 30, 2018): 1840063. http://dx.doi.org/10.1142/s0217984918400638.

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Ba[Formula: see text](PO4)2:0.04Eu[Formula: see text] (S1) and Ba[Formula: see text]Na[Formula: see text](PO4)2:0.04Eu[Formula: see text] (S2) were prepared by solid state reaction. The phases and luminescent properties of the obtained phosphors were characterized. The results demonstrate that the phosphors particles emit an intensive red light under excitation at 395 nm. Both phosphors can be efficiently excited by ultraviolet and blue light, and the emission spectra mainly consist of two emission peaks at 591 nm and 611 nm. The crystallographic sites of Eu[Formula: see text] ions in Ba3(PO4)2 host were discussed on the base of emission spectra and its host crystal structure. By introducing the charge compensator Na[Formula: see text] into the S1 phosphor, its emission intensity was enhanced, indicating that S2 could serve as a promising red-emitting phosphor for UV LED applications.

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Qian, Xian Hua, Da Feng Zhang, and Xi Peng Pu. "Combustion Synthesis and Luminescence Properties of NaY_1-XTb_X(WO₄)₂ Novel Green Phosphors." Advanced Materials Research 295-297 (July 2011): 861–64. http://dx.doi.org/10.4028/www.scientific.net/amr.295-297.861.

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NaY1-xTbx(WO4)2 green phosphors have been synthesized by a facile combustion method. The structure, morphology and luminescence properties of as-synthesized phosphors were characterized via X-ray powder diffraction (XRD), photoluminescence spectra, and decay curve. The XRD results indicate that as-synthesized phosphors exhibit sheelite-type structure without any impurity phase. The as-obtained phosphors emit strong green light centered at 546 nm under ultraviolet light excitation. The lifetimes are about 0.57 ms. The excellent luminescence properties make it a new promising green phosphor for fluorescent lamps application.

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Zhang, Yugen. "Photoacoustic spectra of BaFBr:Eu2+ phosphors." Chemical Physics 219, no. 2-3 (July 1997): 353–57. http://dx.doi.org/10.1016/s0301-0104(97)00113-4.

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Qu, Mingyang, Xiyan Zhang, Xiaoyun Mi, Quansheng Liu, and Shaoqiu Xu. "Novel red-emitting Lu3Te2Li3O12: Eu3+ phosphor with high color purity for n-UV WLEDs." E3S Web of Conferences 185 (2020): 04044. http://dx.doi.org/10.1051/e3sconf/202018504044.

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In this work, a series of red emitting Lu3Te2Li3O12: Eu3+ phosphors were synthesized for the first time by high temperature solid state reaction. The structure was characterized by X-ray diffraction. The excitation spectra, emission spectra and CIE chromaticity coordinate were studied. The phosphors show strong red emission at 611 nm due to the 5D0-7F2 transition of Eu3+ ions. The optimal doping concentration of Eu3+ in LTL host is x = 0.5 due to the concentration quenching mechanism of dipole-dipole interaction. The CIE chromaticity coordinates of the LTL: 0.5Eu3++ phosphor is (0.644,0.355), and the purity of the color is up to 93.61%. The phosphor can be considered as a potential red-emitting candidate for near UV WLEDs.

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Song, Guo Hua, Bin Jiang, Jian Wen Miao, and Bang Dong Ding. "Preparation of Y₄MgSi₃O₁₃:Tb³⁺,Ce³⁺ Green Emitting Phosphor for White Light Emitting Diodes and its Luminescence Study." Advanced Materials Research 415-417 (December 2011): 1333–39. http://dx.doi.org/10.4028/www.scientific.net/amr.415-417.1333.

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The Y4MgSi3O13:Tb3+,Ce3+green phosphors are synthesized by sol-gel method, the preparation temperature, reduction atmosphere and luminescence characteristics of Y4MgSi3O13doped with single Ce3+ions and Ce3+,Tb3+ions have been studied. The excitation and emission spectra of phosphors is determined by fluorescence spectrophotometer. The results show that: luminous intensity of Y4MgSi3O13:Tb3+phosphors increased after doped with Ce3+ions and the optimal doping concentration of Ce3+is 0.04. Y3.94MgSi3O13: 0.02Tb3+,0.04Ce3+green phosphor has the best luminescence characteristics under reduction atmosphere(H2:N2=1:3) at 1000°C, the phosphor gives intense green emission at 550nm originating from the5D4→7F5transition of Tb3+ions.

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Yu, Sheng Fei. "Maleic Anhydride Coating for Strontium Aluminate-Based Phosphors." Advanced Materials Research 79-82 (August 2009): 807–10. http://dx.doi.org/10.4028/www.scientific.net/amr.79-82.807.

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Strontium aluminate-based phosphors SrAl2O4:Eu2+,Dy3+ (SAO-ED) are coated directly by the interfacial coordination chemistry method with maleic anhydride to prevent their hydrolysis in moist air. SEM, XPS, TG and DSC methods are used to characterize the coating. The results showed SAO-ED phosphors coordinated with maleic anhydride by the coordination bond and . The introduction of maleic anhydride doesn’t change the excitation and emission spectra of SAO-ED phosphors, which is proved by the photoluminescence measurement. The SAO-ED phosphor coated with 30 wt. % maleic anhydride has higher water-resistance at the cost of a minor loss of persistent phosphorescence than that of SAO-ED phosphor.

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Wang, Meng Xia, Qin Qin Zhou, Si Qi Ma, Xin Yue Wang, Yi Fan Gang, and Yi Wang. "Study on Spectral Structure and Photoelectric Properties of LED Healthy Light Source." Materials Science Forum 1036 (June 29, 2021): 53–65. http://dx.doi.org/10.4028/www.scientific.net/msf.1036.53.

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LED healthy light source by using a blue LED chip to excite phosphor was prepared successfully. Four kinds of LED commercial phosphors (cyan phosphor with a peak wavelength of 498 nm, green phosphor with 520 nm, yellow-green phosphor with 546 nm, and red phosphor with 628 nm) were selected that could be excited by blue light. A series of experimental studies were carried out on the different amounts of glue, different powder-glue ratio, different combinations of phosphors, and the influence of different driving currents. Trough the optimization of the experimental scheme, we obtained a LED healthy light source spectrum with luminous efficiency higher than 124 lm/w, color rendering index higher than 80, color temperature around 4000 k. These spectra are in good agreement with the full spectrum of sunlight, and the spectral continuity and uniformity are better, which accord with the requirements of bright (dark) vision, and the proportion of the blue spectrum is less than 2.4%, which meets the high quality and healthy lighting requirements of safety and comfort.

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Xiao, Jun, Cong Wang, Xin Min, Xiaowen Wu, Yangai Liu, Zhaohui Huang, and Minghao Fang. "Multiple Energy Transfer in Luminescence-Tunable Single-Phased Phosphor NaGdTiO4: Tm3+, Dy3+, Sm3+." Nanomaterials 10, no. 7 (June 27, 2020): 1249. http://dx.doi.org/10.3390/nano10071249.

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Advances in solid-state white-light-emitting diodes (WLEDs) necessitate the urgent development of highly efficient single-phase phosphors with tunable photoluminescence properties. Herein, the Tm3+, Dy3+, and Sm3+ ions are incorporated into the orthorhombic NaGdTiO4 (NGT) phosphors, resulting in phosphors that fulfill the aforementioned requirement. The emission spectrum of Tm3+ ions overlaps well with the adsorption spectra of both Dy3+ and Sm3+ ions. Under the excitation at 358 nm, the single-phase NaGdTiO4: Tm3+, Dy3+, Sm3+ phosphor exhibits tunable emission peaks in the blue, yellow, and red regions simultaneously, resulting in an intense white-light emission. The coexisting energy transfer behaviors from Tm3+ to Dy3+ and Sm3+ ions and the energy transfer from Dy3+ to Sm3+ ions are demonstrated to be responsible for this phenomenon. The phosphors with multiple energy transfers enable the development of single-phase white-light-emitting phosphors for phosphor-converted WLEDs.

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Sun, Jia Yue, Jin Li Lai, Yi Ning Sun, Zhi Guo Xia, and Hai Yan Du. "Luminescence Properties of Ce³⁺ and Tb³⁺ Doped Strontium Pyroborate Phosphors." Advanced Materials Research 502 (April 2012): 140–43. http://dx.doi.org/10.4028/www.scientific.net/amr.502.140.

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Ce3+ and Tb3+ co-doped Strontium Pyroborate phosphors were synthesized by the solid-state method. The luminescent properties of phosphors were investigated by using the photoluminescence emission and excitation spectra. Under the excitation of near ultraviolet (n-UV) light, Ce3+ and Tb3+ co-doped Strontium Pyroborate phosphors exhibited blue emission corresponding to the f-d transition of Ce3+ ions and green emission bands corresponding to the f-f transition of Tb3+ ions, respectively. In the Ce3+ and Tb3+ co-activated samples the Ce3+ ions strongly sensitize the luminescence of the Tb ions. The Ce3+ and Tb3+ co-doped Strontium Pyroborate phosphor could be considered as one of double emission phosphor for n-UV excited white light emitting diodes.

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Zhang, Peng Yue, Zhang Lian Hong, Xian Ping Fan, and Min Quan Wang. "Luminescence Reducing Mechanism of Cd Doped Y₂O₂S:Ti,Cd Long Afterglow Phosphor." Key Engineering Materials 336-338 (April 2007): 604–6. http://dx.doi.org/10.4028/www.scientific.net/kem.336-338.604.

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Y1.97-xTi0.03CdxO2S (0≤x≤0.06) phosphors with long afterglow were synthesized by solid-state reaction. The photoluminescence spectra, decay curves, thermoluminescnece spectra and Chromaticity coordinate curves were investigated. Results showed that the luminescence and afterglow intensity of Y1.97-xTi0.03CdxO2S (0≤x≤0.06) reduced gradually with increasing Cd2+ ion content while the shape and position of emission peak remain unchanged. The Chromaticity coordinate of present phosphor keeps at (0.5497,0.4415). Furthermore, based on the results of thermoluminescence curves of Ti, Cd single doped and co-doped Y2O2S phosphors, the doped Cd ion reduces the inherent trap depth of Ti single doped Y2O2S:Ti, and induces simultaneously a new trap level in Y2O2S:Ti,Cd phosphor. Thus, it was proposed that the introduced new structure defect by Cd2+ ions should be responsible for the reducing luminescence and afterglow property.

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Tsyretarova, Seseg Yu, Nina M. Kozhevnikova, Nina S. Ereminа, and Gennady M. Mokrousov. "Red and Green Phosphors Glow on the Basis of Oxide Glass-Ceramics Doped with Eu³⁺ and Tb³⁺." Key Engineering Materials 670 (October 2015): 107–12. http://dx.doi.org/10.4028/www.scientific.net/kem.670.107.

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Glass-ceramics phosphors were obtained by the introduction of the crystalline phase NaMg3Sc (MoO4)5:Eu3+,Tb3+ in the glass composition 8SiO2-20B2O3-5Lu2O3-31Bi2O3-36ZnO. The properties were characterized by X-ray diffraction (XRD), photoluminescence (PL) and photoluminescent excitation spectra (PLE). The XRD patterns were indicated NaMg3Sc (MoO4)5:Eu3+,Tb3+ crystallize well with the novel structure type and were assigned to the triclinic phase (space group PĪ, Z = 6). Glass-ceramic phosphors are well-known and promising as solid electrolytes, laser, luminescent and other inorganic materials. Luminescent properties of the phosphors are performed at room temperature. The excitation spectra of Eu-doped phosphor present strong absorption at 300 nm and the sharp peaks in the 350-500 nm range. Under the 394 nm excitation, intense red emission peak at 616 nm corresponding to 5D0→7F2 transition of Eu3+ is observed in the emission spectrum. The luminescence property indicates that the local symmetry of Eu3+ ion has no inversion center. The excitation spectra of Tb-doped phosphor by monitoring wavelength at 546 nm shows the intense broad band from 260 to 420 nm and the line at 234 nm, which is mainly attributed to charge-transfer band transition in MoO42- group, indicating the existence of energy transfer from MoO42- to Tb3+ in the Tb3+:glass-ceramic. The measured emission spectrum of Tb-doped phosphor has intense green emission at 546 nm corresponding to 5D4→7F5 transition of Tb3+, with λex=368 nm. The as-prepared phosphors may find potential applications in the field such as color displays, light-emitting diodes (LEDs) and optoelectronic devices.

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Xu, Xue Wen, Kun Fu, Long Hu, Zun Ming Lu, Xing Hua Zhang, and Cheng Chun Tang. "Synthesis and Photoluminescence Properties of Two-Bands Excited SrSi₂O₂N₂: Yb²⁺ Phosphors." Advanced Materials Research 430-432 (January 2012): 315–18. http://dx.doi.org/10.4028/www.scientific.net/amr.430-432.315.

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The crystal structure and luminescent properties of synthesized SrSi2O2N2: Yb2+ phosphors have been investigated to seek for convention phosphor for white light-emitting diode applications. The Sr1-xYbxSi2O2N2 phosphors have yellow-red luminescence under the exciting of blue light, which is attributed to the 4fn↔4fn-15d transitions of Yb2+. Although the chemical compositions for Sr1-xYbxSi2O2N2 materials are different, no shifts are observed from the excitation and emission spectra.

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Han, Xiu Mei, Deng Hui Ren, Ying Ling Wang, Gui Fang Sun, and Xi Wei Qi. "Luminescent Properties of MgLaLiSi₂O₇:Eu³⁺ Phosphors via Sol-Gel Process." Key Engineering Materials 512-515 (June 2012): 178–81. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.178.

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MgLaLiSi2O7:Eu3+ phosphors have been prepared through the sol-gel process. X-ray diffraction (XRD), thermogravimetric and ddifferential thermal analysis (TG-DTA), FT-IR spectra and photoluminescence spectra were used to characterize the resulting phosphors. FT-IR spectra suggested that crystallized silicates have formed in the powders annealed at 1050°C. The results of XRD indicated that the phosphors crystallized completely at 1050°C. In MgLaLiSi2O7:Eu3+ phosphors, the Eu3+ shows its characteristic red (613nm, 5D0–7F2) emissions.

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Li, Qian, Biao Zhang, Zhilei Wei, Miao He, Hailong Wang, Zhipeng Wei, and Zhongqi Shi. "Effect of Bi3+ ion concentration on crystal structure and luminescent properties of blue–green-emitting Y2O3:Bi3+ phosphors." Functional Materials Letters 13, no. 07 (October 2020): 2050036. http://dx.doi.org/10.1142/s1793604720500368.

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Blue–green-emitting Y2O3 : [Formula: see text]Bi[Formula: see text] ([Formula: see text] = 0.25–1.50 mol.%) phosphors were synthesized by a solution combustion method followed by high temperature annealing. The effect of Bi[Formula: see text] ion concentration on the crystal structure and photoluminescence performance of the phosphors were investigated. The results show that the cell parameter and cell volume of Y2O3host were increased with the Bi[Formula: see text] concentration, and all the phosphor powders exhibited porous lamellar structure with the width of [Formula: see text]500 nm. The emission spectra of the phosphors ([Formula: see text] = 335 nm) consist of three broadband emission spectra centered at 370 nm (3A[Formula: see text]A[Formula: see text], 410 nm (3E[Formula: see text]A[Formula: see text] and 486 nm (3B [Formula: see text]A), respectively. The phosphor exhibited the optimal luminescence performance at [Formula: see text]= 0.50% and the dipole–dipole and quadrupole–quadrupole interactions among Bi[Formula: see text] ions could lead to the concentration quenching. The color coordinates of Y2O3:0.50%Bi[Formula: see text] were (0.1595, 0.2250), indicating that the as-synthesized blue–green phosphors have a broad application prospect in the field of white light-emitting diodes.

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Sun, Jia Yue, Jin Li Lai, and Hai Yan Du. "Synthesis and Luminescence Properties of Red Emitting Phosphors Na₃CaB₅O₁₀:Eu³⁺." Advanced Materials Research 295-297 (July 2011): 547–50. http://dx.doi.org/10.4028/www.scientific.net/amr.295-297.547.

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A series of new Na3CaB5O10:Eu3+ phosphor was synthesized by a solid-state reaction method, and its luminescent properties were investigated. The phase formation of phosphors was confirmed by X-ray powder diffraction (XRD). The excitation spectra exhibited that the phosphors could be effectively excited by near ultraviolet (392 nm) and blue (464 nm) light, which perfectly match the emission wavelength of near-UV light-emitting diodes (LEDs). The emission spectra showed that two characteristic red emission lines peaking at 592 and 613 nm can be obtained upon 394 and 463 excitation with the chromaticity coordinates of (0.6347, 0.3649), which are due to 5D0- 7F1 and 5D0-7F2transitions of Eu3+ ions. The effect of Eu3+ concentration on the emission spectrum of Na3CaB5O10:Eu3+ phosphor was studied. The results showed that the emission intensity increased with increasing Eu3+ concentration, and then decreased because of concentration quenching. The obtained results indicated that this phosphor could be a promising candidate for near-UV white LEDs.

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Wan, Junxi, Youwei Yao, Guoyi Tang, and Yitai Qian. "Hydrothermal Synthesis and Size-Enhanced Chromaticity of Sr2ZnSi2O7:Eu3+ Nanoparticles." Journal of Nanoscience and Nanotechnology 8, no. 3 (March 1, 2008): 1449–53. http://dx.doi.org/10.1166/jnn.2008.18212.

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Red phosphor Sr2ZnSi2O7:Eu3+ nanoparticles with an average diameter of 20 nm were successfully synthesized via a low-temperature hydrothermal route in order to understand the underlying relationship between size and luminescent properties. The nanometer-sized particles result in a distinct improvement in chromaticity and a high quenching concentration. According to emission spectra, the relative intensity of the 5D0 → 7F2 to 5D0 → 7F1 transitions in nanometer-sized phosphors is higher than that of the corresponding bulk material. The better chromaticity results from the more distorted lattices and relatively lower crystal symmetry around the Eu3+ ions, which is ascribed to the large surface area due to the nanometer size of the phosphor. Moreover, the nanometer-sized Sr2ZnSi2O7:Eu3+ red phosphor exhibits a shorter fluorescent lifetime and a blue-shift in excitation spectra compared to that of its bulk counterpart. These results indicate that size-induced enhancement of luminescent properties is an efficient way to obtain red phosphors with better chromaticity.

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Luitel, Hom Nath, Rumi Chand, Toshio Torikai, Mitsunori Yada, and Takanori Watari. "Rare Earth FreeZn3V2O8Phosphor with Controlled Microstructure and Its Photocatalytic Activity." International Journal of Photoenergy 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/410613.

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Microsphere of rare earth free phosphor,Zn3V2O8, with broadband yellowish white emission was synthesized by combustion route and compared with the hydrothermal, sol-gel, and solid state reaction methods. The phosphor samples were characterized by X-ray diffraction and scanning electron microscopy. UV-visible absorption and photoluminescence (PL) emission and excitation spectra were investigated for these phosphors.Zn3V2O8phosphor containing 10 mol% of H3BO3flux exhibited enhanced PL emission showing broadband from 450 nm to 750 nm. Effect of stoichiometry of Zn and V on the host lattice and its effect on the PL emission spectra were studied. Series of Mg3V2O8,Ca3V2O8, and Sr3V2O8phosphors were also synthesized and compared to theZn3V2O8phosphor in terms of PL emission and internal quantum yield, and it was found thatZn3V2O8is the most efficient phosphor among the other phosphors studied with quantum yield of 60%. The visible light irradiated photocatalytic activity of these phosphors was investigated and it was found that the hydrothermalZn3V2O8exhibited enhanced activity.

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Reddy, K. Rajamohan, V. Aruna, T. Balaji, K. Annapuma, and S. Buddhudu. "Photoluminescence spectra of LaOBr:Eu3+ powder phosphors." Materials Chemistry and Physics 52, no. 2 (February 1998): 157–60. http://dx.doi.org/10.1016/s0254-0584(98)80017-5.

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Reddy, K. Rajamohan, K. Annapurna, and S. Buddhudu. "Photoluminescence spectra of BaFCl: Eu2+ phosphors." Materials Letters 27, no. 4-5 (July 1996): 273–74. http://dx.doi.org/10.1016/0167-577x(96)00013-4.

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Huang, Qui Ping, Zhang Lian Hong, Peng Yue Zhang, and Xian Ping Fan. "Preparation and Properties of Ti, Eu Co-Doped Y₂O₂S:0.06Ti,0.08Eu Phosphor with Red Long Afterglow." Key Engineering Materials 336-338 (April 2007): 600–603. http://dx.doi.org/10.4028/www.scientific.net/kem.336-338.600.

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Ti,Eu co-doped Y2O2S:0.06Ti,0.08Eu phosphor with red long afterglow emission from Eu ions was synthesized via traditional sintering method. Results showed that sintering temperature has great influence on the crystal structure, luminescence and afterglow property of the phosphors. The best luminescence and afterglow properties were obtained for the phosphors sintered at 1200°C for 2.5h. Furthermore, only emissions originated from charge transition of Eu3+ was found in the luminescence spectra whereas the afterglow spectra were composed of two sets of emissions: a broad yellow emission band around 565nm and a group of narrow peaks in the wavelength range above 530 nm. The origin of afterglow spectra was discussed: the former is likely related to emission from Ti related traps and the latter is supposed to come from the Eu3+ through an energy transfer process from Ti emission to Eu3+.

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Zhang, Lu, Shuangping Yi, Xiaoxue Hu, Boxin Liang, Weiren Zhao, and Yinhai Wang. "Synthesis and photoluminescence properties of multicolor tunable GdNbO4: Tb3+, Eu3+ phosphors based on energy transfer." Modern Physics Letters B 31, no. 08 (March 20, 2017): 1750051. http://dx.doi.org/10.1142/s0217984917500518.

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A color-tunable phosphor based on Tb[Formula: see text]/Eu[Formula: see text] co-doped GdNbO4 were synthesized by a traditional solid-state reaction method. X-ray powder diffraction (XRD), diffuse reflectance spectra, photoluminescence spectra and decay curves were utilized to characterize the as-prepared phosphors. XRD result indicated that various concentrations Tb[Formula: see text]/Eu[Formula: see text] single-doped and co-doped phosphors were well indexed to the pure GdNbO4 phase. The GdNbO4 host was proved to be a self-activated phosphor with broad absorption range from 200 nm to 325 nm. When Tb[Formula: see text] ions were added into the host lattice, the energy transferring from host to Tb[Formula: see text] was identified. And the broad absorption in the UV region was changed and enhanced. Therefore, we selected Tb[Formula: see text] as the sensitizer ion, and adjusted red component from Eu[Formula: see text] to control the emission color. The energy transfer from Tb[Formula: see text] to Eu[Formula: see text] was confirmed based on the luminescence spectra and decay curves. Furthermore, the energy transmission mechanism was deduced to be the dipole–quadrupole interaction. On the whole, the obtained GdNbO4, GdNbO4:Tb[Formula: see text], and GdNbO4:Tb[Formula: see text], Eu[Formula: see text] phosphors may have potential application in the UV white-light-emitting diodes (w-LEDs) and display devices.

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Sun, Jia Yue, Liu Han, Qiu Mei Di, and Qi Guang Xu. "Synthesis and Luminescence Properties of Na₃YSi₂O₇:Sm³⁺, Eu³⁺ Phosphor." Applied Mechanics and Materials 633-634 (September 2014): 306–9. http://dx.doi.org/10.4028/www.scientific.net/amm.633-634.306.

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Novel Na3YSi2O7: Sm3+, Eu3+phosphors for white light-emitting diodes were prepared by high-temperature solid-state reaction. The photoluminescence excitation and emission spectra, energy transfer from Eu2+to Tb3+are investigated in detail. The current research suggests that Na3YSi2O7: Sm3+, Eu3+phosphor is a potential candidate for application in Phosphor-converted LEDs.

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Yang, Rong, and Huidong Tang. "Synthesis and luminescence properties of red-emitting K2MgSiO4:Eu3+ phosphors." International Journal of Modern Physics B 31, no. 16-19 (July 26, 2017): 1744058. http://dx.doi.org/10.1142/s0217979217440581.

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A novel phosphor, K2MgSiO4:Eu[Formula: see text], was synthesized by a solid-state reaction method. The phase formation was checked by X-ray powder diffraction. The photoluminescence excitation, emission spectra, decay curve and CIE coordinates of samples with different Eu[Formula: see text] ion concentrations were investigated in detail. The excitation spectra show a broad wavelength range of 225–470 nm. The K2MgSiO4:Eu[Formula: see text] phosphors exhibit highly red emission peaking at about 616 nm which is assigned to the 5D[Formula: see text]F2 transition of Eu[Formula: see text]ions under the excitation of near-ultraviolet (NUV) (394 nm) light. The critical quenching concentration of Eu[Formula: see text] doped in the K2MgSiO4: Eu[Formula: see text] phosphors was about 10 mol.% and the concentration quenching mechanism was dipole–dipole interactions between Eu[Formula: see text] ions. The results indicate that K2MgSiO4:Eu[Formula: see text] is a potential red phosphor candidate for NUV-pumped white light emitting diodes.

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Lin, Cuikun, Bo Zhao, Zhenling Wang, Min Yu, Huan Wang, Deyan Kong, and Jun Lin. "Spherical SiO2 @ GdPO4 : Eu3+ Core–Shell Phosphors: Sol–Gel Synthesis and Characterization." Journal of Nanoscience and Nanotechnology 7, no. 2 (February 1, 2007): 542–48. http://dx.doi.org/10.1166/jnn.2007.102.

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Nanocrystalline GdPO4 : Eu3+ phosphor layers were coated on non-aggregated, monodisperse and spherical SiO2 particles by Pechini sol–gel method, resulting in the formation of core–shell structured SiO2 @ GdPO4 : Eu3+ particles. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), photoluminescence (PL), low-voltage cathodoluminescence (CL), time-resolved PL spectra and lifetimes were used to characterize the core–shell structured materials. Both XRD and FT-IR results indicate that GdPO4 layers have been successfully coated on the SiO2 particles, which can be further verified by the images of FESEM and TEM. Under UV light excitation, the SiO2 @ GdPO4 : Eu3+ phosphors show orange-red luminescence with Eu3+ 5D0–7F1 (593 nm) as the most prominent group. The PL excitation and emission spectra suggest that an energy transfer occurs from Gd3+ to Eu3+ in SiO2 @ GdPO4 : Eu3+ phosphors. The obtained core–shell phosphors have potential applications in FED and PDP devices.

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Lin, Cuikun, Bo Zhao, Zhenling Wang, Min Yu, Huan Wang, Deyan Kong, and Jun Lin. "Spherical SiO2 @ GdPO4 : Eu3+ Core–Shell Phosphors: Sol–Gel Synthesis and Characterization." Journal of Nanoscience and Nanotechnology 7, no. 2 (February 1, 2007): 542–48. http://dx.doi.org/10.1166/jnn.2007.18045.

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Nanocrystalline GdPO4 : Eu3+ phosphor layers were coated on non-aggregated, monodisperse and spherical SiO2 particles by Pechini sol–gel method, resulting in the formation of core–shell structured SiO2 @ GdPO4 : Eu3+ particles. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), photoluminescence (PL), low-voltage cathodoluminescence (CL), time-resolved PL spectra and lifetimes were used to characterize the core–shell structured materials. Both XRD and FT-IR results indicate that GdPO4 layers have been successfully coated on the SiO2 particles, which can be further verified by the images of FESEM and TEM. Under UV light excitation, the SiO2 @ GdPO4 : Eu3+ phosphors show orange-red luminescence with Eu3+ 5D0–7F1 (593 nm) as the most prominent group. The PL excitation and emission spectra suggest that an energy transfer occurs from Gd3+ to Eu3+ in SiO2 @ GdPO4 : Eu3+ phosphors. The obtained core–shell phosphors have potential applications in FED and PDP devices.

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Lu, Hao Ying, and Hua Wei Yang. "The Characteristics of High-Temperature Synthesized YAG:Ce Nano-Phosphors." Applied Mechanics and Materials 145 (December 2011): 194–98. http://dx.doi.org/10.4028/www.scientific.net/amm.145.194.

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In the last decade, nanosized phosphors had attracted a lot of interest, no matter in light emitting layers or thermal remove materials. Many methods had been investigated to synthesize nanosized phosphors, but they usually need expensive cost and complicated procedures, furthermore they resulted in the difficulties in mass production. In our work, chemical co-precipitation was applied to prepare YAG:Ce precursor. Then, the mixed precipitation was heated to 900°C with air in the furnace. After 1 hour, the synthesis was completed. From TEM images, the average particle size is about 40 nm and all XRD diffraction peaks of phosphor powders were consistent to JCPDS data of YAG. Photoluminescence spectra show the nanosized YAG:Ce phosphor synthesized at 1000°C possessed the strongest photoluminescence intensity at wavelength 540 nm. From photoluminescence excitation spectra, the strongest absorption peak was observed at wavelength 460 nm in all samples. At synthesis temperature 1000°C, YAG with 0.5% Ce3+ was observed to emit the strongest yellow light. It is believed our synthesis can provide an easy and low-cost choice to synthesize YAG:Ce nanophosphors at high temperature.

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Seo, Yeon Woo, Mi Noh, Byung Kee Moon, Jung Hyun Jeong, Hyun Kyoung Yang, and Jung Hwan Kim. "Synthesis and Luminescent Properties of Eu3+ Doped CaGd4O7 Phosphors by Solvothermal Reaction Method." Journal of Nanoscience and Nanotechnology 15, no. 10 (October 1, 2015): 8028–33. http://dx.doi.org/10.1166/jnn.2015.11265.

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Eu3+ doped CaGd4O7 phosphors have been newly synthesized using a solvothermal reaction method and sintered at 1400 °C. The phase, composition, morphologies, and photoluminescent properties of the phosphors have been well characterized by means of the X-ray diffraction (XRD) patterns, energy dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FE-SEM), photoluminescence (PL) spectroscopy, and decay curves, respectively. The XRD patterns of the as-prepared phosphors confirm their monoclinic structure and the FE-SEM images reveal flower-like morphology, formed through agglomeration. The calculated size of the crystallites was approximately 83 nm. The photoluminescence excitation (PLE) spectra of CaGd4O7: Eu3+ phosphors consist of a broad band due to the charge transfer (CT) electronic transition, and several sharp peaks that can be attributed to the f–f transitions of Eu3+ and Gd3+. The PL spectra exhibited a stronger red emission corresponding to the 5D0→7F2 transition. The CIE chromaticity coordinates of the phosphors were calculated and all the chromaticity coordinates have been placed in the red spectral region. These luminescent powders are expected to have potential applications for white light-emitting diodes (WLEDs) and optical display systems.

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Huang, Chun Ying, and Man Hua Wan. "Spectral Analysis of Ca_2-XBO₃Cl:xDy³⁺ Phosphors." Materials Science Forum 663-665 (November 2010): 54–57. http://dx.doi.org/10.4028/www.scientific.net/msf.663-665.54.

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PL spectra of Ca2-xBO3Cl:xDy3+ phosphors excited by 390 nm n-UV light. The intensity of both blue and yellow emissions starts to increases with the growing contents of Dy3+ ions, the strongest intensity of Dy3+ emission courses in the Ca1.95BO3Cl:0.05Dy3+ phosphor, subsequently it decreases with further adding Dy3+ ions due to concentration quenching. it can be concluded that the environment of Dy3+ ions may be less influenced due to the clustering of Dy3+ ions in the investigated phosphors after concentration quenching.

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Polisadova, Elena F., Vitaly A. Vaganov, Damir T. Valiev, Habibula A. Abdullin, A. A. Marhabaeva, and D. D. Kerimbaev. "Cathodoluminescence Properties of Commercial Phosphors for White LED." Key Engineering Materials 712 (September 2016): 367–71. http://dx.doi.org/10.4028/www.scientific.net/kem.712.367.

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The results of the study of spectral and decay kinetic characteristics of the pulse cathodoluminescence (PCL) for the group of industrial “white” LEDs phosphors with different composition of the host and dopants are presented. The quantitative characteristics of the PCL: position and half-width of the luminescence spectra, the luminescence decay times were determined.

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Kaya, Selvin Yesilay, Bekir Karasu, Guray Kaya, and Erkul Karacaoğlu. "Influences of Eu²⁺ and Dy³⁺ Contents on the Properties of Long Afterglow Strontium Aluminate Phosphors." Advances in Science and Technology 62 (October 2010): 88–94. http://dx.doi.org/10.4028/www.scientific.net/ast.62.88.

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The detailed preparation process of Eu2+ and Dy3+ ion co-doped phosphor powders in Sr4Al14O25:Eu2+/Dy3+ phosphor system with bluish-green long afterglow produced by solid state reaction method under reducing atmosphere is here reported. X-ray diffraction (XRD), scanning electron microscopy (SEM), and particle size analysis were made to assign the effects of Eu and Dy ions on the luminescent properties of the synthesized phosphors, which were determined by measuring the photoluminescence spectra. The maximum emission intensity of these phosphors under excitation was investigated. As a result, the relevant values were obtained from the phosphorescent pigment with 0.21% and 0.05% molar percent of Eu2+ and Dy3+.

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Han, Xiu Mei, Shu Ai Hao, Ying Ling Wang, Gui Fang Sun, and Xi Wei Qi. "Luminescent Properties of Zn₂SiO₄:Eu³⁺,Dy³⁺ Phosphors via Sol-Gel Process." Applied Mechanics and Materials 217-219 (November 2012): 733–36. http://dx.doi.org/10.4028/www.scientific.net/amm.217-219.733.

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Zn2SiO4:Eu3+, Dy3+ phosphors have been prepared through the sol-gel process. X-ray diffraction (XRD), thermogravimetric and ddifferential thermal analysis (TG-DTA), FT-IR spectra and photoluminescence spectra were used to characterize the resulting phosphors. The results of XRD indicated that the phosphors crystallized completely at 1000oC. In Zn2SiO4:Eu3+,Dy3+ phosphors, the Eu3+ and Dy3+ show their characteristic red(613nm, 5D0-7F2), blue (481nm, 4F9/2–6H15/2) and yellow (577nm, 4F9/2–6H13/2) emissions.

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Zhang, Jiao, Yanmin Yang, Fang Yu, Yanzhou Liu, Boning Han, Chao Mi, and Linlin Liu. "Synthesis and Luminescence Properties of La2W2O9:Eu3+ Micron-Crystals." Journal of Nanoscience and Nanotechnology 16, no. 4 (April 1, 2016): 3852–56. http://dx.doi.org/10.1166/jnn.2016.11791.

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La2W2O9:2%Eu3+ phosphors were synthesized by a typical hydrothermal procedure. The samples were characterized by X-ray diffraction and scanning electron microscope (SEM). X-ray diffraction analysis showed that a stock solution pH value equal to 9 is the ideal value, while the crystallization of the hydroxyl sodium yttrium tungstate crystal is improved by increasing the PH values of stock solution within limits. Meanwhile, SEMs of different pH values were recorded. Additionally, photoluminescence excitation (PLE) and emission (PL) spectra were measured. It was found that this phosphor can be effectively excited by C–T band (266 nm) and ultraviolet light 342 nm. The wavelengths at 342 nm fit in nicely with the whole visible region, thus the La2W2O9:2%Eu3+ phosphors emit white light. Furthermore, the annealing temperature’s impact on PLE and PL spectra was also studied. The Eu3+-doped La2W2O9 phosphor may be a better candidate than current method for solid-state lighting applications.

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Han, Xiu Mei, J. Lin, M. Yu, C. K. Lin, Xi Wei Qi, Zhi Yong Yu, and Xiao Qin Wang. "Luminescence Properties of Spherical Phosphors SrSiO₃:Eu³⁺." Key Engineering Materials 336-338 (April 2007): 619–21. http://dx.doi.org/10.4028/www.scientific.net/kem.336-338.619.

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Spherical SiO2 particles have been successfully coated with SrSiO3:Eu3+ phosphor layers through a sol-gel process. The resulted core-shell phosphors were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), photoluminescence spectra as well as kinetic decays. The XRD results demonstrate that the SrSiO3:Eu3+ layers begin to crystallize on the SiO2 particles after annealing at 1000oC. The obtained core-shell phosphors have perfect spherical shape. The Eu3+ shows a strong photoluminescence (PL) (dominated by 5D0-7F2 red emission at 612 nm).

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Khaidukov, Nicholas, Angela Pirri, Maria Brekhovskikh, Guido Toci, Matteo Vannini, Barbara Patrizi, and Vladimir Makhov. "Time- and Temperature-Dependent Luminescence of Manganese Ions in Ceramic Magnesium Aluminum Spinels." Materials 14, no. 2 (January 16, 2021): 420. http://dx.doi.org/10.3390/ma14020420.

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Samples of magnesium aluminum spinel ceramics doped with manganese ions were prepared by a high-temperature solid-state reaction method; their potential as red-emitting phosphors was analyzed using a time-resolved luminescence spectroscopy technique, from room temperature to 10 K. It was found that in the red spectral range, the luminescence spectra of manganese ions in the MgAl2O4 spinel showed a narrow band peaking at 651 nm due to the emission of Mn4+ and a broader emission band in the region of 675 ÷ 720 nm; the ratio of intensities for these bands depends on the synthesis conditions. By applying a special multi-step annealing procedure, the MgAl2O4:Mn4+ phosphor containing only tetravalent manganese ions, Mn4+, was synthesized. Broad-band far-red emission observed from MgAl2O4:Mn and Mg1.25Al1.75O3.75F0.25:Mn phosphors, prepared by a conventional method of a solid-state reaction, was interpreted as coming from Mn3+ ions.

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Shinde, K. N., and S. J. Dhoble. "Luminescence in Rare Earth Activated AlPO₄ Phosphor." Advanced Materials Research 306-307 (August 2011): 171–75. http://dx.doi.org/10.4028/www.scientific.net/amr.306-307.171.

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Rare earth activated AlPO4 phosphors were synthesized by solid-state reactions and the completion of the synthesis was confirmed by X-ray diffraction (XRD) pattern. Under near-ultraviolet (nUV) light, the Eu3+ emission in AlPO4 consists of the transitions from 5D0 to 7FJ shows orange/red region and the AlPO4 :Dy3+ phosphor shows an efficient blue and yellow band emissions, which originates from the 4F9/26H15/2 and 4F9/26H13/2 transitions of Dy3+ ion. The excitation spectra of the phosphors are extending from 300 to 400 nm, which are characteristics of nUV excited LED. The effect of the Eu3+ and Dy3+ concentration on the luminescence properties of AlPO4 phosphors is also studied.

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Tang, An, Liduo Gu, Fengxiang Shao, Xidong Liu, Yongtao Zhao, Haijun Chen, and Hongsong Zhang. "Influence of Bi3+ content on photoluminescence of InNbO4:Eu3+,Bi3+ for white light-emitting diodes." Materials Science-Poland 35, no. 2 (July 26, 2017): 435–39. http://dx.doi.org/10.1515/msp-2017-0053.

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Abstract A series of red-emitting phosphors InNbO4:Eu3+,Bi3+ was prepared by a high temperature solid-state reaction. The structure, size distribution and luminescence properties of the phosphors were respectively characterized by X-ray diffraction (XRD), laser particle size and molecular fluorescence spectrometer. The XRD results indicate that the phase-pure samples have been obtained and the crystal structure of the host has not changed under the Eu3+ and Bi3+ co-doping. The test of size distribution shows that the phosphor has a normal size distribution. The excitation spectra illustrate that the dominant sharp peaks are located at 394 nm (7F0→5L6) and 466 nm (7F0→5D2). Meanwhile, the emission spectra reveal that the phosphors excited by the wavelength of 394 nm or 466 nm have an intense red-emission line at 612 nm owing to the 5D0→7F2 transition of Eu3+. Bi3+ doping has not changed the peak positions except the photoluminescence intensity. The emission intensity is related to Bi3+ concentration, and it is up to the maximum when the Bi3+-doping concentration is 4 mol%. Due to good photoluminescence properties of the phosphor, the InNbO4:0.04Eu3+,0.04Bi3+ may be used as a red component for white light-emitting diodes.

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Cao, Chunyan, Weiping Qin, Jisen Zhang, Jishuang Zhang, Yan Wang, Ye Jin, Guodong Wei, Guofeng Wang, and Lili Wang. "Multicolor Up-Conversion Emissions of Tm3+/Er3+/Yb3+ Tri-Doped YF3 Phosphors." Journal of Nanoscience and Nanotechnology 8, no. 3 (March 1, 2008): 1384–87. http://dx.doi.org/10.1166/jnn.2008.18200.

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Tm3+/Er3+/Yb3+ tri-doped yttrium fluoride (YF3) phosphors were prepared by a facile hydrothermal method. X-ray topographic analysis found that the phosphors were crystallized products. Their sizes and morphologies were characterized by scanning electron microscopy (SEM, Hitachi S-4800), which indicated that most of the YF3 phosphors were hundreds of nanometers in size. Up-conversion (UC) spectra were recorded under 980-nm diode laser excitation at room temperature with a fluorescence spectrometer (Hitachi F-4500). Plenty of UC emissions of Tm3+ and Er3+ were observed from ultraviolet to red. For Tm3+ ions, a five-photon process (∼291 nm and ∼347 nm), a four-photon process (∼362 nm and ∼452 nm), and a three-photon process (∼475 nm) were identified in the UC spectra. The UC emissions from the Er3+ were: ∼380 nm, ∼408 nm, ∼521 nm, ∼537 nm, and ∼652 nm. Therefore, cyan-white light can be observed by the naked eye at 980-nm excitation, even under low excitation power density. By comparing the UC spectra of the phosphors annealed at different temperatures, we found that the intensity of the UC luminescence increased as annealing temperature increased. Furthermore, the spectral dependencies on Tm3+ doped concentrations were studied. The energy transfer processes and fluorescence dynamics in the tri-doped system are currently being investigated.

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Wang, Wen Deng, Fu Qiang Huang, Yu Juan Xia, Xin Ping Lin, Min Ling Liu, and Jian Lin Shi. "Influence of Mechanical Milling and Annealing Atmosphere on the Photoluminescence Properties of ZnS:Cu,Cl Phosphors." Key Engineering Materials 368-372 (February 2008): 312–14. http://dx.doi.org/10.4028/www.scientific.net/kem.368-372.312.

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ZnS:Cu,Cl phosphors were synthesized by high temperature (1200 °C) solid state reaction, mechanical milling (rotation speed = 0, 75, 150, 250 and 350 r / min) and the final annealing at 750 °C for 1 h in different atmospheres (hydrogen sulfide, sealed evacuated silica tubes and Ar). The as-prepared phosphors were characterized by X-ray powder diffraction and photoluminescence spectra. It was found that mechanical milling led to width increases of diffraction peaks. Both the mechanical milling and atmosphere play important roles in the photoluminescence performance of the phosphors. Some phosphors prepared by the three-step method possess higher photoluminescence performances than the normal one-step method. Particularly, the luminescence intensity of the phosphor milled at the rotation speed of 75 r / min and then treated in Ar atmosphere is about one time higher than that prepared by the normal one-step process.

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Journal articles on the topic 'Phosphors – Spectra'

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