OPTIK
·
2017
·
IF 0.835
Renping Cao,Jijun Huang,Xiangfeng Ceng,Zuofu Hu,Ting Chen,Wen Hu,Xinqin Zhang
Ca 3 Nb 2 O 8 :Sm 3+ phosphor is synthesized by solid-state reaction method in air. Host Ca 3 Nb 2 O 8 emits blue light with excitation 260 and 314 nm, and its emission band peaking at ∼460 nm is attributed to the 3 T 1,2 → 1 A 1 transations in [Nb 2 O 8 6− ] group. Ca 3 Nb 2 O 8 :Sm 3+ phosphor with excitation 314 nm shows a systematically tunable emission by adjusting Sm 3+ ion concentration , and only emits reddish-orange light with excitation 407 nm. Excitation band indicates that Ca 3 Nb 2 O 8 :Sm 3+ phosphor may be effectively excited by (∼407 nm) near ultraviolet light-emitting diode chip. The optimal Sm 3+ ion concentration is ∼5 mol% in Ca 3 Nb 2 O 8 :Sm 3+ phosphor. Emission intensity of Ca 3 Nb 2 O 8 :Sm 3+ phosphor may be increased ∼1.4 times by co-doping Li + ions as charge compensator and fluxing agent roles. The experimental results will contribute to studying novel Sm 3+ -doped luminescent materials.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
OPTIK
·
2016
·
IF 0.742
Renping Cao,Dedong Peng,Haidong Xu,Zhiyang Luo,Hui Ao,Siling Guo,Jingwei Fu
Sr 3 (VO 4 ) 2 :Eu 3+ and Sr 3 (VO 4 ) 2 :Eu 3+ , Li + phosphors are synthesized by solid-state reaction method in air. X-ray diffraction patterns indicate that all samples are pure phase Sr 3 (VO 4 ) 2 . The host Sr 3 (VO 4 ) 2 with excitation 348 nm emits yellow-green light. Emission spectrum of Sr 3 (VO 4 ) 2 :Eu 3+ phosphor with excitation 335 nm contains a broad emission band peaking at ∼540 nm due to V 5+ → O 2− charge transfer and some narrow emission bands owing to the 4 f – 4 f electron transations of Eu 3+ ion in the range of 400–780 nm. With excitation 394 nm, only emision bands derived from Eu 3+ ion are observed. Emission intensity of Sr 3 (VO 4 ) 2 :Eu 3+ phosphor can be improved obviously due to charge compensation and fluxing agent role of Li + ion when Li + ion is co-doped. The optimal Eu 3+ doping concentration is ∼5 mol%. The energy transfer process between [VO 4 ] 3− group and Eu 3+ ion is observed and analyzed by emission spectrum in Sr 3 (VO 4 ) 2 :Eu 3+ phosphor. The luminous mechanism of Sr 3 (VO 4 ) 2 :Eu 3+ phosphor is explained by energy transfer and energy level diagram of [VO 4 ] 3− group and Eu 3+ ion.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Reziwanguli Yantake,Palidan Aierken,Aierken Sidike
The cyan emission band contains blue and green light regions, which can simplify the fabrication process of white light-emitting diodes and help promote the development of solid-state lighting. In this paper, a series of Eu 2+ singly doped and Eu 2+ and Li + co-doped cyan light-emitting KAlSiO 4 : x Eu 2+ , y Li + materials were synthesized using the high temperature solid-state method. It was found that the incorporation of 10% Li + could increase the emission intensity of the KAlSiO 4 :0.02Eu 2+ sample by up to a factor of ∼3. This also shifted the emission color of the sample from blue-cyan (472 nm) to cyan (485 nm), and the quantum yield was increased from 71.5% to 93.3%. When the temperature is increased to 150 °C, the peak emission intensity was increased from 75.9% to 92.7% of that at room temperature. DFT calculations were used to demonstrate that the KAlSiO 4 phosphor host possesses a wide bandgap of 4.86 eV and the experimentally-determined optical bandgap of the phosphor was 5.6 eV. The phosphor was combined with a commercial red phosphor, and these together were used as the emitting components in a white LED package. The characteristics of the white LED when using two representative samples of the phosphor (KAlSiO 4 : 0.02Eu 2+ and KAlSiO 4 : 0.02Eu 2+ , 0.1Li + ) were examined; these white LEDs had color rendering indices of 82 and 95, and color temperatures of 5656 K and 4126 K respectively. This work demonstrates the significant potential that KAlSiO 4 :0.02 Eu 2+ , 0.1 Li + phosphors have in the field of LED lighting.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
LUMINESCENCE
·
2017
·Vol. 32
·期 6
·908-912
·
IF 1.509
Renping Cao,Jinlong Zhang,Wudi Wang,Qianglin Hu,Wensheng Li,Wen Ruan,Hui Ao
CaSnO 3 :Bi 3+ blue-emitting phosphor was synthesized using a high-temperature solid-state reaction method in air. The crystal structures and luminescence properties were investigated. A broad emission band peaking at ~448 nm upon excitation at 262 and 308 nm was observed in the range 330–680 nm at room temperature due to 3 P 1 → 1 S 0 transition of the Bi 3+ ion. The chromaticity coordinate was (0.1786, 0.1665). The optimal Bi 3+ ion concentration was ~0.6 mol% in CaSnO 3 :Bi 3+ phosphor. The emission spectrum of CaSnO 3 :Bi 3+ phosphor showed a blue-shift with increasing temperature from 50 to 300 K due to the influence of temperature on the electron transition of the Bi 3+ ion. The emission intensity of CaSnO 3 :Bi 3+ phosphor may be increased ~1.45 times by co-doping Li + ions as a charge compensator and fluxing agent. The luminescence mechanism is explained by a configurational coordinate diagram of Bi 3+ ion in CaSnO 3 :Bi 3+ phosphor.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2018
·
IF 2.88
Yichen Jin,Tao Pang
Upconversion luminescence and optical temperature sensing properties of Yb 3+ /Er 3+ /Li + tri-doped ZnMoO 4 phosphors were investigated. It has been demonstrated that Li + doping affected not only the local symmetry of Yb 3+ and Er 3+ but also the distribution of them in the host lattice. As a result, the significantly improved green upconversion luminescence was obtained when excited at 980 nm. The pumping power dependent photo-thermal behavior was used to evaluate the reliability of upconversion temperature sensing. An accurate temperature scale was established by eliminating the impact of thermal effect, and the sensing ability was evaluated via a comparison with the results reported in literatures.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Ping Wang,Peixi Wang,Jie Wang,Shoutao Lv,Jiaqing Wang,Hui Zheng
With the rapid development of wireless charging technology, there is a growing demand for ferrite materials with high permeability, high saturation magnetic induction intensity, and low power loss. This study aims to enhance the electromagnetic performance of NiCuZn ferrite by co-doping Nb 5+ and Li + . The influence of the doping levels Nb 5+ and Li + on the morphology, crystal structure, and electromagnetic properties of NiCuZn ferrite were studied in detail. Structural analysis shows that the lattice constant decreases as the Nb 5+ -Li + doping concentration increases, and the NiCuZn ferrite exhibits a high density and homogeneous microscopic morphology at the optimum concentration of x = 0.004. Specifically, at a doping concentration of x = 0.004, the magnetic permeability at 1 MHz measured at 1112.1, the saturation magnetic induction intensity reached 458.98 mT, and the power loss was minimized to 521.85 kW/m 3 , demonstrating significant improvement in the transmission power of wireless charging applications.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2020
·
IF 7.1
Junqing Chang,Mati Horprathum,Dianhui Wang,Gang Meng,Zanhong Deng,Bin Tong,Pinit Kidkhunthod,Tiantian Dai,Meng Li,Hongyu Liu,Wei Tong,Shimao Wang,Xiaodong Fang
Though p-type NiO possesses excellent catalytic oxidation property toward volatile organic compounds (VOCs), intrinsic low sensitivity of NiO (arising from the hole accumulation layer configuration in ambient air atmosphere sensor) restricts its promising applications in VOCs detection. In this study, Sc and Li were proposed to modulate the (surface) properties of NiO nanosheet-flowers based sensors. At the optimal 2 at.% Sc and 5 at.% Li doping ratio (Ni 0.93 Sc 0.02 Li 0.05 O), the sensitivity to 100 ppm ethanol is 118.4 (105 times higher than that of pure NiO), which is comparable to or even higher than most of reported NiO based sensors. Moreover, Ni 0.93 Sc 0.02 Li 0.05 O sensor exhibits a low detection limit of 10 ppb, excellent repeatability and long-term stability (∼30 % decline of response after 7 months). Apart from regulating the carrier concentration, defect characterizations indicate a noticeable increase of stabilized surface oxygen vacancy (O V ) defects and Ni 3+ cations by Sc 3+ and Li + co-doping, which greatly facilitate the adsorption of VOCs molecule (revealed by density functional theory calculation) as well as the subsequent VOCs/NiO interfacial charge interaction, thus contribute to the superior sensing performances. This work demonstrates that co-doping offers an effective avenue for boosting the performances of (p-type) oxide sensors.
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2023
·
IF 4.9
Wei Zhang,Changjian Wang,Xusheng Qiao,Xianping Fan
The rapid development of phosphor-converted white light emitting diodes (pc-WLEDs) requires new red phosphors with efficient and thermally stable luminescence for high-quality warm-white lighting. However, it is still a challenge to discover red phosphors with facile synthesis, high internal quantum efficiency (IQE), excellent thermal stability and high color purity. Herein, a novel red-emitting Eu 3+ activated barium dialuminum digermanate (BaAl 2 Ge 2 O 8 , BAGO) phosphor showing strong red emission at 610 nm was prepared. The IQE is improved from 32.91% to 78.84% by employing a charge compensation strategy. The lithium-ion co-doped BAGO:Eu 3+ phosphor exhibits a nearly twofold increase in integral photoluminescence (PL) intensity and the high color purity reaches 94.17%. Impressively, the PL intensity of the BAGO:Eu 3+ ,Li + phosphor drops by only 2.6% at 150 °C of that at room temperature. Finally, the pc-WLED using the red BAGO:Eu 3+ ,Li + phosphor exhibits white light with the chromaticity coordinate of (0.3515, 0.3495), a high color-rendering index of 92 and a low correlated color temperature of 4746 K. All these results manifest that BAGO:Eu 3+ ,Li + phosphor is a suitable red phosphor for near-ultraviolet (NUV) chip-based pc-WLEDs.
研究领域:
材料科学
·
光电
·
发光二极管
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2024
·Vol. 12
·期 11
·3980-3987
·
IF 5.7
Yuechao Tang,Jin Yang,Qinan Mao,Yang Ding,Guojun Zheng,Lang Pei,Jiasong Zhong
Driven by the demand for miniaturized broadband near-infrared (NIR) light sources, considerable effort has been dedicated to developing Cr3+-activated phosphors. However, in many cases, the multivalent nature of the Cr ion is adverse to achieving highly efficient emission of Cr3+. Herein, strategic Li+ co-doping was employed to boost the NIR emission of BaGe4O9:Cr3+. In the phosphor, Li+ ions play a pivotal role in the distribution of Cr3+ on the two octahedral sites and the elimination of Cr4+ and crystal defects, leading to a 42.9-fold enhancement of Cr3+ emission. The obtained BaGe4O9:Cr3+,Li+ exhibited broadband emission centered at 808 nm, with an FWHM of 177 nm and an internal quantum efficiency of 61.3%. A fabricated pc-LED device utilizing the phosphor showcased an NIR radiant flux of 24.8 mW and a photoelectric efficiency of 8.9% at 100 mA. Furthermore, the application of the pc-LED in bio-imaging, night vision and information encryption was successfully demonstrated.
研究领域:
材料科学
·
光电技术
·
光子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）