Browsing by Author "Chen, Teng-Ming"

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A Green-Emitting Phosphor Sr(3)La(PO(4))(3):Ce(3+),Tb(3+) with Efficient Energy Transfer for Fluorescent Lamp
(2010-01-01)
Kuo, Te-Wen
;
Chen, Teng-Ming
;
應用化學系
;
Department of Applied Chemistry
Green-emitting phosphors of Sr(3)La(PO(4))(3):Ce(3+),Tb(3+) have been synthesized by a solid-state reaction. The energy transfer from Ce(3+) to Tb(3+) is a resonant type via a dipole-dipole mechanism with an energy-transfer critical distance of 7.6 angstrom. By utilizing the principle of energy transfer and appropriate tuning of activator contents, we have also made an attempt to observe a strong green emission performance displayed by this phosphor for use as a coating material on compact fluorescent lamps (CFLs). The results clearly indicate that the luminous efficiency based on Sr(3)(La(0.67)Ce(0.08)Tb(0.25))(PO(4))(3) was found to be 69 lm/W. The good luminous efficiency and lumen maintenance (2000 h, 91.8%) of the green-emitting CFL demonstrate that this phosphor can be suitable for application on a short UV fluorescent lamp. Additionally, the Sr(3)(La(0.67)Ce(0.08)Tb(0.25))(PO(4))(3) green phosphor has advantages of environmental friendliness and low cost. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3384662] All rights reserved.
A Green-Emitting Phosphor Sr3La(PO4)(3):Ce3+,Tb3+ with Efficient Energy Transfer for Fluorescent Lamp
(2010-01-01)
Kuo, Te-Wen
;
Chen, Teng-Ming
;
應用化學系
;
Department of Applied Chemistry
Green-emitting phosphors of Sr3La(PO4)(3):Ce3+,Tb3+ have been synthesized by a solid-state reaction. The energy transfer from Ce3+ to Tb3+ is a resonant type via a dipole-dipole mechanism with an energy-transfer critical distance of 7.6 angstrom. By utilizing the principle of energy transfer and appropriate tuning of activator contents, we have also made an attempt to observe a strong green emission performance displayed by this phosphor for use as a coating material on compact fluorescent lamps (CFLs). The results clearly indicate that the luminous efficiency based on Sr-3(La0.67Ce0.08Tb0.25)(PO4)(3) was found to be 69 lm/W. The good luminous efficiency and lumen maintenance (2000 h, 91.8%) of the green-emitting CFL demonstrate that this phosphor can be suitable for application on a short UV fluorescent lamp. Additionally, the Sr-3(La0.67Ce0.08Tb0.25)(PO4)(3) green phosphor has advantages of environmental friendliness and low cost. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3384662] All rights reserved.
A highly sensitive system for urea detection by using CdSe/ZnS core-shell quantum dots
(2007-03-15)
Huang, Chin-Ping
;
Li, Yaw-Kuen
;
Chen, Teng-Ming
;
應用化學系
;
Department of Applied Chemistry
An original and novel assay system with urease as a catalyst and CdSe/ZnS quantum dots (QDs) as an indicator has been developed for quantitative analysis of urea. By mixing urease and QDs, the determination of urea can be performed in a quantitative manner. The detection is based on the enhancement of QD photoluminescence (PL) intensity, which is correlated to the enzymatic degradation of urea. By controlling the buffer concentration and pH, PL enhancement due to the degradation of urea is linear in the urea concentration ranging from 0.01 to 100 mM. This property makes the urease/QDs system to be a promising urea-biosensing system. The newly developed system is a superior design and possesses many advantages, including its simple preparation, low cost, no enzyme immobilization required, high flexibility, and good sensitivity. (c) 2006 Elsevier B.V. All rights reserved.
A morphologically stable host material for efficient phosphorescent green and red organic light emitting devices
(2008-11-28)
Ho, Meng-Huan
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Balaganesan, Banumathy
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Chu, Ta-Ya
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Chen, Teng-Ming
;
Chen, Chin H.
A carbazole-based host material, 4,4'-N,N'-[di(3, 6-di(t-butyl)carbazole]biphenyl (ttbCBP), with four t-butyl steric spacers on peripheral carbazole moieties was effectively synthesized through Friedel-Crafts Alkylation. Owing to the presence of sterically hindered t-butyl groups, ttbCBP exhibits a high glass transition temperature (175 degrees C) and is morphologically stable. This host material also preserves the characteristics of wide band-gap of 3.2 eV and high triplet energy of 2.64 eV. In addition, ttbCBP has been shown to be effective hosts for green and red phosphorescent emitters in organic electrophosphorescent devices. (C) 2008 Elsevier B.V. All rights reserved.
A new approach for quantitative determination of glucose by using CdSe/ZnS quantum dots
(2008-03-14)
Huang, Chin-Ping
;
Liu, Shu-Wei
;
Chen, Teng-Ming
;
Li, Yaw-Kuen
;
應用化學系
Quantitative detection of glucose is an important issue in food industry, various biotechnological processes and medication of metabolic disorders. Many ways have been developed to approach this target. In this study, we demonstrated a simple assay system containing glucose oxidase (GOD) and CdSe/ZnS quantum dots (QDs) for specific and quantitative detection of glucose, The role of QDs functioned as an "indicator" to reveal the acidity change of the assay system resulting from the enzymatic oxidation of glucose. By controlling the initial buffer conditions of the assay system at 10 mM or 30 mM phosphate, pH 8.0, the quench ratio of PL intensity of QDs at 586 nm was found to be linear to the tested glucose in the range of 0.2-10 mM or 2-30 mM, respectively. The assay system also provides a convenient way to determine the glucose concentration by visuahzing the color change of QDs fluorescence. As compare to most of the existing methods, this newly developed system possesses many advantages, including simplicity, low cost, high flexibility, and good sensitivity. Furthermore, no complicated chemical modification and enzyme immobilization were needed in this system. (C) 2007 Elsevier B.V. All rights reserved.
A Novel Single-Composition Trichromatic White-Light Ca(3)Y(GaO)(3)(BO(3))(4):Ce(3+),Mn(2+),Tb(3+) Phosphor for UV-Light Emitting Diodes
(2011-02-10)
Huang, Chien-Hao
;
Chen, Teng-Ming
;
應用化學系
;
Department of Applied Chemistry
A novel single-composition white-emitting phosphor Ca(3)Y(GaO)(3)(BO(3))(4):Ce(3+), Mn(2+),Tb(3+) has been synthesized by a high-temperature solid-state reaction. The spectral overlap between the emission band of Ce(3+) and the excitation band of Mn(2+), which supports the occurrence of the energy transfer from Ce(3+) to Mn(2+), has been studied and demonstrated to be a resonant type via a dipole-quadrupole mechanism. Because there was no spectral overlap between the emission spectra of Ce(3+) and excitation band of Tb(3+) in our study, no energy transfer from Ce(3+) to Tb(3+) was observed, Indicating that Ce(3+) and Tb(3+) were coexcited. Through effective resonance-type energy transfer and coexcitation, the chromaticity coordinates of Ca(3)Y(GaO)(3)(BO(3))(4):Ce(3+),Mn(2+),Tb(3+) phosphors can be tuned from (0.152, 0.061) for Ca(3)Y-(GaO)(3)(BO(3))(4):Ce(3+) to (0.562, 0.408) for Ca(3)Y(GaO)(3)(BO(3))(4):Mn(2+), and eventually reaching (0.314, 0.573) for Ca(3)Y(GaO)(3)(BO(3))(4):Tb(3+). A white light-emitting diode (LED) was fabricated by using the white-emitting single-composition (Ca(0.97))(3)(Y(0.92))(GaO)(3)(BO(3))(4):0.01Ce(3+),-0.03Mn(2+),0.07Tb(3+) pumped by a 365 nm UV-chip. Our results indicated that the CIE chromaticity coordinates and correlated color temperature (CCT) for white UV-LEDs were (0.31, 0.33) and 6524 K, respectively. Therefore, our novel white Ca(3)Y(GaO)(3)(BO(3))(4):Ce(3+),Mn(2+),Tb(3+) can serve as a key material for phosphor-converted white-light UV-LEDs.
A Novel Single-Composition Trichromatic White-Light Ca3Y(GaO)(3)(BO3)(4):Ce3+,Mn2+,Tb3+ Phosphor for UV-Light Emitting Diodes
(2011-02-10)
Huang, Chien-Hao
;
Chen, Teng-Ming
;
應用化學系
;
Department of Applied Chemistry
A novel single-composition white-emitting phosphor Ca3Y(GaO)(3)(BO3)(4):Ce3+, Mn2+,Tb3+ has been synthesized by a high-temperature solid-state reaction. The spectral overlap between the emission band of Ce3+ and the excitation band of Mn2+, which supports the occurrence of the energy transfer from Ce3+ to Mn2+, has been studied and demonstrated to be a resonant type via a dipole-quadrupole mechanism. Because there was no spectral overlap between the emission spectra of Ce3+ and excitation band of Tb3+ in our study, no energy transfer from Ce3+ to Tb3+ was observed, Indicating that Ce3+ and Tb3+ were coexcited. Through effective resonance-type energy transfer and coexcitation, the chromaticity coordinates of Ca3Y(GaO)(3)(BO3)(4):Ce3+,Mn2+,Tb3+ phosphors can be tuned from (0.152, 0.061) for Ca3Y-(GaO)(3)(BO3)(4):Ce3+ to (0.562, 0.408) for Ca3Y(GaO)(3)(BO3)(4):Mn2+, and eventually reaching (0.314, 0.573) for Ca3Y(GaO)(3)(BO3)(4):Tb3+. A white light-emitting diode (LED) was fabricated by using the white-emitting single-composition (Ca-0.97)(3)(Y-0.92)(GaO)(3)(BO3)(4):0.01Ce(3+),-0.03Mn(2+),0.07Tb(3+) pumped by a 365 nm UV-chip. Our results indicated that the CIE chromaticity coordinates and correlated color temperature (CCT) for white UV-LEDs were (0.31, 0.33) and 6524 K, respectively. Therefore, our novel white Ca3Y(GaO)(3)(BO3)(4):Ce3+,Mn2+,Tb3+ can serve as a key material for phosphor-converted white-light UV-LEDs.
A Novel Tunable Green- to Yellow-Emitting beta-YFS:Ce(3+) Phosphor for Solid-State Lighting
(2011-08-01)
Wu, Yun-Chen
;
Wang, De-Yin
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Chen, Teng-Ming
;
Lee, Chi-Shen
;
Chen, Kuo-Ju
A Ce(3+)-activated fluorosulfide phosphor (beta-YFS: Ce(3+)) was synthesized by solid-state reaction in a sealed tube. The crystal structure has been refined from the XRD profiles and there are two different crystallographic rare earth sites, namely, Y(1) and Y(2), where the Ce(3+) ions occupied. The emission band with a maximum at 495 nm of beta-Y(0.99)Ce(0.01) FS phosphor was characterized by the 4f-5d transitions of Ce(3+) ion. With increasing Ce(3+) concentration, the emission variations were observed from 495 to 547 nm. When beta-YFS:Ce(3+) phosphors were utilized to incorporate with n-UV/blue chip, greenish-white light with color rendering index of 65-77 were obtained. The results indicate that the tunable green- to yellow-emitting beta-YFS:Ce(3+) can serve as a potential phosphor for incorporation in fabrication for solid-state lighting. The preparation, spectroscopic characterization, quantum efficiency, thermal-quenching behavior, and related LED device data are also presented.
A Novel Tunable Green- to Yellow-Emitting beta-YFS:Ce3+ Phosphor for Solid-State Lighting
(2011-08-01)
Wu, Yun-Chen
;
Wang, De-Yin
;
Chen, Teng-Ming
;
Lee, Chi-Shen
;
Chen, Kuo-Ju
A Ce3+-activated fluorosulfide phosphor (beta-YFS: Ce3+) was synthesized by solid-state reaction in a sealed tube. The crystal structure has been refined from the XRD profiles and there are two different crystallographic rare earth sites, namely, Y(1) and Y(2), where the Ce3+ ions occupied. The emission band with a maximum at 495 nm of beta-Y0.99Ce0.01 FS phosphor was characterized by the 4f-5d transitions of Ce3+ ion. With increasing Ce3+ concentration, the emission variations were observed from 495 to 547 nm. When beta-YFS:Ce3+ phosphors were utilized to incorporate with n-UV/blue chip, greenish-white light with color rendering index of 65-77 were obtained. The results indicate that the tunable green- to yellow-emitting beta-YFS:Ce3+ can serve as a potential phosphor for incorporation in fabrication for solid-state lighting. The preparation, spectroscopic characterization, quantum efficiency, thermal-quenching behavior, and related LED device data are also presented.
A Single-Phased Emission-Tunable Phosphor Ca(9)Y(PO(4))(7):Eu(2+),Mn(2+) with Efficient Energy Transfer for White-Light-Emitting Diodes
(2010-01-01)
Huang, Chien-Hao
;
Chen, Teng-Ming
;
Liu, Wei-Ren
;
Chiu, Yi-Chen
;
Yeh, Yao-Tsung
A series of single-composition emission-tunable Ca(9)Y(PO(4))(7):Eu(2+),Mn(2+) phosphors were synthesized by solid-state reaction. The energy transfer from Eu(2+) to Mn(2+) in Ca(9)Y(PO(4))(7) host matrix was studied and demonstrated to be a resonant type via a dipole-quadrupole mechanism with the critical distance of similar to 11 angstrom. The wavelength-tunable white light can be realized by coupling the emission bands centered at 486 and 638 nm ascribed to the contribution From Eu(2+) and Mn(2+), respectively. By properly tuning the relative composition of Eu(2+)/Mn(2+), chromaticity coordinates of (0.31, 0.33) can be achieved under excitation at 250-440 nm. Moreover, white-light-emitting diodes were fabricated through the integration of 365 nm chips and single composition white-light-emitting phosphors (Ca(0.975)Eu(0.01)Mn(0.015))(9)Y(PO(4))(7) into a single package shows a cool white light of 7200 K, color rendering index of 76, and color coordinates of (0.30, 0.31) close to that of ideal white light can be achieved.
A Single-Phased Emission-Tunable Phosphor Ca9Y(PO4)(7):Eu2+,Mn2+ with Efficient Energy Transfer for White-Light-Emitting Diodes
(2010-01-01)
Huang, Chien-Hao
;
Chen, Teng-Ming
;
Liu, Wei-Ren
;
Chiu, Yi-Chen
;
Yeh, Yao-Tsung
A series of single-composition emission-tunable Ca9Y(PO4)(7):Eu2+,Mn2+ phosphors were synthesized by solid-state reaction. The energy transfer from Eu2+ to Mn2+ in Ca9Y(PO4)(7) host matrix was studied and demonstrated to be a resonant type via a dipole-quadrupole mechanism with the critical distance of similar to 11 angstrom. The wavelength-tunable white light can be realized by coupling the emission bands centered at 486 and 638 nm ascribed to the contribution From Eu2+ and Mn2+, respectively. By properly tuning the relative composition of Eu2+/Mn2+, chromaticity coordinates of (0.31, 0.33) can be achieved under excitation at 250-440 nm. Moreover, white-light-emitting diodes were fabricated through the integration of 365 nm chips and single composition white-light-emitting phosphors (Ca0.975Eu0.01Mn0.015)(9)Y(PO4)(7) into a single package shows a cool white light of 7200 K, color rendering index of 76, and color coordinates of (0.30, 0.31) close to that of ideal white light can be achieved.
A study on the luminescence properties of CaAlBO(4): RE(3+) (RE=Ce, Tb, and Eu) phosphors
(2008)
Liu, Wei-Ren
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Chiu, Yi-Chen
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Tung, Chien-Yueh
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Yeh, Yao-Tsung
;
Jang, Shyue-Ming
A series of new phosphors of CaAlBO(4):RE(3+) (RE=Ce, Tb, Eu) were synthesized by conventional solid-state reactions. The X-ray diffraction data indicate that a pure phase of CaAlBO(4):RE(3+) can be successfully obtained. The photoluminescence (PL) spectra, quantum efficiency, and CIE coordinates of CaAlBO(4):RE(3+) were investigated. The PL and PL excitation spectra indicate that the emission wavelengths of CaAlBO(4):Ce(3+) are 372 and 398 nm (with full width at half maximum of 33 nm) attributed to the 4f(6)5d-4f(7) transition of the Ce(3+) activator, respectively. CaAlBO(4):Tb(3+) displays green emission at 483, 543, 584, and 620 nm, while CaAlBO(4):Eu(3+) shows a dominating emission peak at 621 nm, which is attributed to the Eu(3+) (5)D(0)-(7)F(2) transition. The quantum efficiencies of optimized CaAlBO(4):Ce(3+), CaAlBO(4):Tb(3+), and CaAlBO(4):Eu(3+) were found to be 43, 21, and 19%, respectively. The phosphors may provide a new kind of luminescent material under UV excitation. (C) 2008 The Electrochemical Society.
All Inorganic Perovskite Quantum Dots Hybrid Green Light-Emitting Diode with Stable Performance
(2018-01-01)
Yu, Chung-Ping
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Chung, Meng-Ting
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Chen, Tzu-Yu
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Huang, Yu-Ming
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Huang, Chung-Ping
A silica-coated inorganic perovskite quantum dot hybrid light-emitting diodes is aged continuously in high and low light intensity conditions. Both blue and ultra-violet-pumped samples showed stable performances up to 104 hours.
alpha-(Y,Gd)FS:Ce(3+): a novel red-emitting fluorosulfide phosphor for solid-state lighting
(2011-01-01)
Wu, Yun-Chen
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Chen, Yi-Chin
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Wang, De-Yin
;
Lee, Chi-Shen
;
Sun, Ching-Cherng
A novel Ce(3+)-doped fluorosulfide phosphor, alpha-(Y,Gd)FS:Ce(3+), was first investigated as a new candidate for application in phosphor-converted light emitting diodes (LEDs) and thin-film electroluminescence (TFEL) devices. The detailed crystal structure was investigated based on X-ray diffraction profiles using Rietveld refinement methods. This phosphor shows good absorption ranging from ultraviolet to visible region and broad saturated red emission, which can be tuned from 660 to 672 nm, and the photoluminescence (PL) intensity was demonstrated to be effectively enhanced by Gd(3+) substitution.
alpha-(Y,Gd)FS:Ce3+: a novel red-emitting fluorosulfide phosphor for solid-state lighting
(2011-01-01)
Wu, Yun-Chen
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Chen, Yi-Chin
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Wang, De-Yin
;
Lee, Chi-Shen
;
Sun, Ching-Cherng
A novel Ce3+-doped fluorosulfide phosphor, alpha-(Y,Gd)FS:Ce3+, was first investigated as a new candidate for application in phosphor-converted light emitting diodes (LEDs) and thin-film electroluminescence (TFEL) devices. The detailed crystal structure was investigated based on X-ray diffraction profiles using Rietveld refinement methods. This phosphor shows good absorption ranging from ultraviolet to visible region and broad saturated red emission, which can be tuned from 660 to 672 nm, and the photoluminescence (PL) intensity was demonstrated to be effectively enhanced by Gd3+ substitution.
An efficient green-emitting Ba5Si2O6Cl6:Eu2+ phosphor for white-light LED application
(2017-01-01)
Dutta, Somrita
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Chen, Teng-Ming
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應用化學系
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Department of Applied Chemistry
A series of novel green-emitting Ba5Si2O6Cl6:Eu2+ (BSOC:Eu2+) phosphors were synthesized via the high-temperature solid-state reaction route. The phase identification, elemental distribution, reflectance spectra, luminescence, and thermal stability of the BSOC:Eu2+ phosphor and its applicability in white light-emitting diodes (WLEDs) were investigated in detail. The broad excitation spectrum was observed from UV to blue light which generated a broadband emission peaking at 510 nm for the present phosphor with a good quantum efficiency of 44% and thereby it is promising for solid-state lighting applications. Temperature-dependent luminescence measurements of the BSOC:Eu2+ phosphor from 25 degrees C to 250 degrees C were performed to obtain the thermal stability of the present phosphor. Finally, a WLED was fabricated using the green-emitting BSOC:Eu2+ phosphor and commercially available red and blue phosphors pumped with a 400 nm blue chip. The CIE parameters such as color coordinate, color rendering index, color correlated temperature and luminous efficacy of radiation of the fabricated LED were measured. The suitable excitation spectra, efficient and broad emission band and excellent color parameters suggest that the synthesized phosphor could be a potential material for WLED application.
An Investigation on Stable and Continuous Operation of Hybrid Perovskite Quantum Dot Light Emitting Diodes
(2019-01-01)
Cho, Yu-Yun
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Hsu, Shun-Chieh
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Huang, Yu-Ming
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Shih, Hsiang-Yun
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Lee, Ting-Yu
Two different package structures of hybrid perovskite quantum dots light emitting diodes were demonstrated with stable and continuous light emission. With boron nitride nanoparticles, the lifetime of device is expected to be thousands of hours.
An Investigation on the Luminescence and Ce(3+) -> Eu(2+) Energy Transfer in Ca(9)Y(PO(4))(7):Ce(3+),Eu(2+) Phosphor
(2011-01-01)
Huang, Chien-Hao
;
Luo, Liyang
;
Chen, Teng-Ming
;
應用化學系
;
Department of Applied Chemistry
A series of Ce(3+)- and Eu(2+)-coactivated Ca(9)Y(PO(4))(7) phosphors were synthesized by high temperature solid-state reactions. The Ca(9)Y(PO(4))(7):Ce(3+), Eu(2+) phosphor showed two emission bands under 292 nm excitation:the one observed at 342 nm was attributed to the 4f(0)5d(1) -> 4f(1) transition of Ce(3+) ion emission, and the other found at 492 nm was assigned to the 4 f(6)5d(1) -> 4f(7) transition of Eu(2+) ions. Through an effective resonance-type energy transfer, the Ca(9)Y(PO(4))(7):Ce(3+), Eu(2+) phosphors exhibit a systematically varied hues from ultraviolet to blue-greenish and the relative intensity of ultraviolet and blue-greenish emissions can be tuned by properly tuning the relative dopant composition of Ce(3+)/Eu(2+). The energy transfer from a sensitizer Ce(3+) to an activator Eu(2+) in Ca(9)Y(PO(4))(7) host matrix was studied and demonstrated to be a resonant type via a dipole-dipole mechanism based on the decay lifetime analysis. Furthermore, we have calculated the critical distance for Ce(3+) -> Eu(2+) energy transfer to be about 30.7 angstrom by both concentration quenching and spectral overlap methods. (C) 2011 The Electrochemical Society. [DOI: 10.1149/2.029111jes] All rights reserved.
An Investigation on the Luminescence and Ce3+ -> Eu2+ Energy Transfer in Ca9Y(PO4)(7):Ce3+,Eu2+ Phosphor
(2011-01-01)
Huang, Chien-Hao
;
Luo, Liyang
;
Chen, Teng-Ming
;
應用化學系
;
Department of Applied Chemistry
A series of Ce3+- and Eu2+-coactivated Ca9Y(PO4)(7) phosphors were synthesized by high temperature solid-state reactions. The Ca9Y(PO4)(7):Ce3+, Eu2+ phosphor showed two emission bands under 292 nm excitation:the one observed at 342 nm was attributed to the 4f(0)5d(1) -> 4f(1) transition of Ce3+ ion emission, and the other found at 492 nm was assigned to the 4 f(6)5d(1) -> 4f(7) transition of Eu2+ ions. Through an effective resonance-type energy transfer, the Ca9Y(PO4)(7):Ce3+, Eu2+ phosphors exhibit a systematically varied hues from ultraviolet to blue-greenish and the relative intensity of ultraviolet and blue-greenish emissions can be tuned by properly tuning the relative dopant composition of Ce3+/Eu2+. The energy transfer from a sensitizer Ce3+ to an activator Eu2+ in Ca9Y(PO4)(7) host matrix was studied and demonstrated to be a resonant type via a dipole-dipole mechanism based on the decay lifetime analysis. Furthermore, we have calculated the critical distance for Ce3+ -> Eu2+ energy transfer to be about 30.7 angstrom by both concentration quenching and spectral overlap methods. (C) 2011 The Electrochemical Society. [DOI: 10.1149/2.029111jes] All rights reserved.
Anomalous luminescence from Yb2+-doped Ca2PO4Cl
(2014-04-01)
Wang, De-Yin
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Chiu, Yi-Chen
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Huang, Chien-Hao
;
Wu, Yun-Chen
;
Chen, Teng-Ming
The photoluminescence of Ca2PO4Cl:Yb2+ has been investigated and compared with that of Ca2PO4Cl: Eu2+, and the application of Ca2PO4Cl:Yb2+ for white LED has been evaluated. The excitation spectra of Ca2PO4Cl:Yb2+ are dominated by an intense excitation band at 395 nm. Under near DV excitation at 395 nm, Ca2PO4Cl:Yb2+ shows a broad asymmetric emission with maximum at 490 nm. This emissions result from two different Yb2+ centers is evidenced by the low temperature (T=100 K) emission spectrum. Yb2+ luminescence differs significantly from that of Eu2+, most notably in the structure of emission spectra, and is characterized by a much broader emission band and lower quenching temperature. Such anomalous luminescence from Yb2+ is ascribed to the de-excitation process of the Yb2+-trapped exciton state. Ca2PO4Cl:Yb2+ has external quantum efficiency of 24% and exhibits 40% of luminescence quenching at 100 degrees C in the air and, therefore, these results reveal its limited potential in the fabrication of white-light LEDs. (C) 2013 Elsevier B.V. All rights reserved.