JOURNAL OF LUMINESCENCE
·
2019
·
IF 2.961
Qiying Huang,Weihao Ye,Guangqi Hu,Xiaotang Liu
Bi 3+ and Mn 4+ co-activated Mg 3.5 Ge 1.25 O 6 phosphors were synthesized via a solid-state method in air. Codoping Bi 3+ into the matrix leads to effective enhancement of the deep-red emssion (659 nm) compared to Bi 3+ -free samples. The spectroscopic properties are discussed based on the Bi 3+ (6s 2 )→Ge 4+ (3d 10 ) metal-to-metal charge transfer and energy transfer between Bi 3+ and Mn 4+ . All samples emit deep-red emission ascribed to 2 E g → 4 A 2g transition of Mn 4+ . We have carried out the X-ray power diffraction (XRD), photoluminescence spectrum (PL), field emission scanning electron microscope (FESEM), fourier transform infrared spectroscopy (FT-IR) and UV–Vis absorption measurement to investigate the influences induced by Bi 3+ incorporation.
研究领域:
材料科学
·
光学农业
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2016
·
IF 2.758
Renping Cao,Xiangfeng Ceng,Jijun Huang,Xiuwen Xia,Siling Guo,Jingwei Fu
Novel double-perovskite Sr 2 ZnWO 6 :Mn 4+ (SZW:Mn 4+ ) phosphor is synthesized by high-temperature solid-state reaction method in air. SZW:Mn 4+ phosphor with excitation at 325 and 526 nm emits deep-red light, the chromaticity coordinate is (0.7315,0.2685), and the emission band peaking at ~702 nm within the range 640–760 nm is assigned to the 2 E→ 4 A 2 transition of Mn 4+ ion. The influences of “Mn 4+ - ligand” bonding and crystal field strength to emission properties of Mn 4+ ion are analyzed. The optimal Mn 4+ ion concentration in SZW:Mn 4+ phosphor is ~0.8 mol%. Lifetime of SZW:Mn 4+ phosphor decreases from 554.77 to 401.35 μs with increasing Mn 4+ ion concentration in the range of 0.2–1.0 mol%. The lifetime data and decay curves indicate that there is only a single type of Mn 4+ ion luminescent center in SZW:Mn 4+ phosphor. The luminous mechanism of SZW:Mn 4+ phosphor is analyzed by Tanabe-Sugano energy level diagram of Mn 4+ in the octahedron together with the simple energy level diagram. The experimental results are helpful to research the influences of the neighboring coordination environment around Mn 4+ and host crystal structure to the luminescence properties of Mn 4+ ion and to deeply understand other Mn 4+ -dopedmaterials.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2016
·Vol. 122
·期 4
·1-6
·
IF 1.444
Cao Renping,Ceng Dong,Liu Pan,Yu Xiaoguang,Guo Siling,Zheng Guotai
LaAlO 3 :Mn 4+ and LaAlO 3 :Mn 4+ , Na + deep red-emitting phosphors are synthesized by a solid-state reaction method in air. Their crystal structures, lifetimes, and luminescence properties are investigated, respectively. PLE spectrum monitored at 730 nm contains three PLE bands peaking at ~276, 325, and 500 nm within the range 200–550 nm, and PL spectrum with excitation 325 nm exhibits two PL band peaks located at ~703 and 730 nm owing to anti-stokes vibronic sidebands associated with the excited state 2 E of Mn 4+ ion and the 2 E → 4 A 2 transition of Mn 4+ ion, respectively. The optimal Mn 4+ doping concentration is ~0.8 mol%. Lifetime of LaAl 0.992 O 3 :0.8 %Mn 4+ phosphor is ~0.92 ms. Na + ion as charge compensator can improve obviously the luminescence properties of LaAlO 3 :Mn 4+ phosphor due to the charge compensation. The luminous mechanism of Mn 4+ ion is explained by using Tanabe–Sugano diagram of Mn 4+ ion in octahedral crystal field. The contents of this paper will be helpful to develop novel Mn 4+ -doped materials and improve their luminescence properties.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ECS Journal of Solid State Science and Technology
·
2023
·Vol. 12
·期 7
·076018
·
IF 2.2
Xuan Gu,Xiao-Yu Sun,Zheng He
Mn4+ doped BaLa2Al2O7 phosphors were developed after a sintering process at 1400 °C for 3 h. The phase and luminescence performance of them were researched. The XRD patterns confirm single phase of the Mn4+ doped BaLa2Al2O7 phosphors. Upon the UV light excitation, the Mn4+ doped BaLa2Al2O7 phosphors emit strong deep-red emission. The concentration-dependence emission spectra demonstrate that the critical concentration for Mn4+ ion in BaLa2Al2O7 host is 0.006. On the basis of the temperature-dependence emission spectra, the activation energy for Mn4+ has been calculated as 0.292 eV, which suggests excellent thermostability of the Mn4+ activated BaLa2Al2O7 phosphors.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2025
·
IF 3.6
Qingdong Gou,Junwei Jiang,Hui Ao,Siling Guo,Ting Chen,Xiaochun Li,Jingjing Duan,Renping Cao
Light can improve the growth and development of most plants, and the red/deep-red light in the 600–760 nm region is very good for phytochrome red and phytochrome far-red of plants, causing a great interest in the research and development of the deep-red-emitting luminescence materials. In this work, a pure phase LiAlSi 2 O 6 :Mn 4+ with monoclinic crystal structure and only luminous center (Mn 4+ ) is synthesized successfully in air. The excitation spectrum of LiAlSi 2 O 6 :Mn 4+ covers the region from 220 to 550 nm owing to the O 2− - Mn 4+ charge transfer and the 4 A 2g → 4 T 1g and 4 T 2g transitions of Mn 4+ . We observe the deep-red emission of LiAlSi 2 O 6 :Mn 4+ with emission peak at ∼663 nm in the range of 600–850 nm due to the transitions 2 E g → 4 A 2g of Mn 4+ and analyze the luminous mechanism. The optimal doping concentration of Mn 4+ (0.1mol%) is determined by the concentration dependent emission spectra. We analyze the concentration quenching mechanism and investigate the lifetimes of LiAlSi 2 O 6 :Mn 4+ with different Mn 4+ concentration. The good thermal stability of LiAlSi 2 O 6 :Mn 4+ is confirmed via the temperature dependent emission spectra. The potential applications of LiAlSi 2 O 6 :Mn 4+ in plant growth LED lighting are estimated by comparison of spectral properties of LiAlSi 2 O 6 :Mn 4+ and plant.
研究领域:
材料科学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Xiaoshuai Zhang,Wen Xiong,Chengrun Liu,Zixuan Wang,Xiaoyan Yu,Xiaojie Li,Guodong Zhang,Panlai Li,Zhijun Wang
Exploring oxide-based deep red light-emitting phosphors is crucial for indoor plant lighting applications. In particular, designing Eu 2+ deep red emission in inorganic solids is challenging. In this paper, a cation substitution strategy was used to replace the Ca 2+ ions in the matrix with a certain concentration of Sr 2+ ions. A series of spectrally red-shifted Ca 1-x Sr x Sc 2 O 4 :Eu 2+ deep red phosphors were obtained under 460 nm light excitation. The substitution of Sr 2+ ions changes the local crystal field environment of Eu 2+ . The spectral shift from 656 nm to 702 nm was achieved by changing the centroid shift, the degree of polyhedral distortion and the lattice disorder. Combined with the need for practical applications, Ca 0.5 Sr 0.5 Sc 2 O 4 :0.01Eu 2+ phosphor and blue chip have been made into phosphor-converted light-emitting diodes for plant lighting, and the results of plant lighting experiments show that Ca 0.5 Sr 0.5 Sc 2 O 4 :0.01Eu 2+ phosphor has a certain application potential in plant lighting. In addition, this study will guide the exploration of new oxide-based deep red phosphors with Eu 2+ activation and for the realization of tunable emission through cation substitution.
研究领域:
材料科学
·
光学工程
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2021
·
IF 3.599
Zuizhi Lu,Yingbin Meng,Hua Fan,Jiangying Lu,Xiaoying Zhong,Yingjun Ou,Hairong Mo,Liya Zhou
Mn 4+ -doped double-perovskite LaTiSbO 6 (LTS) phosphors were fabricated via traditional high-temperature sintering reaction. The crystal structure, composition , and luminescent properties of the LTS:Mn 4+ phosphors were studied. The PLE spectrum presents two broad bands that are centered at 356 and 475 nm, and they match the UV and blue chips. A broad emission band that is centered at 685 nm is presented in the PL spectrum. The quantum efficiency is 21.3%. A red light LED device was also fabricated with LTS:0.007Mn 4+ phosphor and an InGaN chip (465 nm). The CCT, CRI, and luminous efficiency of the LED are 4215 K, 73.4, and 62.1 Im/W, respectively. The LED spectrum meets the needs of plant growth in blue and red light. Therefore, the LED fabricated by LTS:Mn 4+ phosphor is a potential light source for plant growth.
研究领域:
材料科学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 9
·2619-2630
·
IF 4
Xuejiao Wang,Xiaowen Feng,Maxim S. Molokeev,Huiling Zheng,Qiushi Wang,Chunyan Xu,Ji-Guang Li
Phosphors that exhibit tunable broadband emissions are highly desired in multi-functional LEDs, including pc-WLEDs and pc-NIR LEDs. In this work, broadband emissions were obtained and modulated in the unexpectedly wide spectral range of 517–609 nm for (Lu0.99−xGdxBi0.01)2WO6 phosphors by tuning the Gd3+ content (x = 0–0.99). The effects of Gd3+ doping on phase constituents, particle morphology, crystal structure, and photoluminescence were systematically investigated. Broadband green emission was obtained from Gd3+-free (Lu0.99Bi0.01)2WO6 phosphors (x = 0), whose emission intensity was enhanced by 50% with 5 at% Gd3+ (x = 0.05). The phase transition happened when x > 0.50 and the broadband red-NIR emission was obtained when x = 0.75–0.99. Three luminescence centers were proved to be responsible for the broadband green emissions via crystal structure, spectral fitting and fluorescence decay analysis. A pc-WLED with a high color rendering index (Ra = 91.3), a stable emission color, and a low color temperature (3951 K) was fabricated from the (Lu0.94Gd0.05Bi0.01)2WO6 broadband green phosphor, and an LED device that simultaneously emits high color rendering index white light and NIR light was obtained with the (Gd0.99Bi0.01)2WO6 broadband red-NIR phosphor. Night vision and noninvasive imaging were also demonstrated using the latter LED device.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Optical Materials
·
2024
·Vol. 12
·期 22
·2400722
·
IF 8
Zhen-Yu Ma,Bai-Sheng Zhu,Xue-Chen Ru,Yi-Chen Yin,Li-Zhe Feng,Guan-Jie Ding,Mei-Yu Zhou,Yong-Hui Song,Hong-Min Zhou,Cheng-Ming Wang,Jing-Ming Hao,Hong-Bin Yao
Inorganic CsPbI 3 perovskite has great potential to fabricate deep-red light-emitting diodes (LEDs) owing to excellent color purity, thermal stability, and carrier mobility. However, fabricating high-quality CsPbI 3 thin films for high-performance LEDs remains challenging. While it is demonstrated that hydrogen bonds between organic ammonium cations and molecule additives can lead to high-quality organic–inorganic hybrid perovskite films, this method cannot be applied to CsPbI 3 thin films due to the absence of hydrogen bonds between Cs + ions and additives. In this study, an amorphous complex-seed-crystal growth process to fabricate high-quality γ -CsPbI 3 cuboid crystallite thin films, is reported. During the initial annealing, the metastable intermediates formed crystal nucleate seeds and transformed into amorphous complex intermediates, maintaining stability at an elevated temperature for perovskite crystallization. With prolonged annealing, the amorphous complex around the nucleate seeds gradually converts to γ -CsPbI 3 perovskite, enabling us to fabricate CsPbI 3 thin films with high crystallinity and orientation. The resulting deep-red LEDs exhibit a peak external quantum efficiency (EQE) of 16.5% and a high maximum luminance of 3158 cd m −2 . Moreover, the devices show significantly suppressed efficiency roll-off, maintaining an EQE of 14.8% even under a high current density of 500 mA cm −2 .
研究领域:
材料科学
·
光电技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2025
·
IF 7.2
Xiaoshuai Zhang,Xi Wang,Tao Yin,Xuping Han,Panlai Li,Xiaoyan Yu,Zixuan Wang,Chengrun Liu,Zhijun Wang
The market demand for environmentally controlled agricultural indoor lighting is gradually increasing due to environmental pollution and drastic changes in the natural climate. Generally, matrix K 3 YSi 2 O 7 (phase 1) is difficult to synthesize compared to K 3 YSi 2 O 7 (phase 2), which has been illustrated by theoretical calculations. In this paper, large quantities of pure phase K 3 YSi 2 O 7 (phase 1) matrix were obtained by the substitution engineering strategy (Ca 2+ →Y 3+ ). Subsequently, Eu 2+ was doped to obtain a thermally stable ultra-wideband deep red light-emitting phosphor with an emission band centered at 721 nm and a full width at half maximum of 186 nm under 450 nm light excitation. It is noteworthy that compared with K 3 YSi 2 O 7 :Eu (phase 2), K 3 Ca 0.3 Y 0.7 Si 2 O 7 :Eu 2+ (phase 1) is superior in terms of emission wavelength, full width at half maximum, and thermal stability. Furthermore, the spectrum resemblance between its emission spectrum and the photosensitive pigment P fr was calculated to be 97.5%, which set the stage for subsequent plant lighting applications. Finally, light-emitting diode devices were prepared using K 3 Ca 0.3 Y 0.7 Si 2 O 7 :Eu 2+ phosphor for plant lighting experiments, and plants grown under deep red light emitting diode light show more luxuriant growth. The results show that the phosphor K 3 Ca 0.3 Y 0.7 Si 2 O 7 :Eu 2+ has promising applications in indoor plant culture. Meanwhile, the successful implementation of ion substitution engineering also provides a new strategy for transitions in host systems.
研究领域:
材料科学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2020
·
IF 3.28
Xiaoyong Huang,Qi Sun,Balaji Devakumar
Deep-red-emitting phosphors are important for fabricating light-emitting diodes (LEDs) toward applications in plant growth lighting. Herein, we reported on novel efficient deep-red-emitting Mn 4+ -activated Ca 2 LuTaO 6 (CLT) double-perovskite phosphors. A series of CLT: x Mn 4+ ( x = 0.1, 0.2, 0.4, 0.6, 0.8, and 1.0 mol%) samples were prepared by the conventional high-temperature solid-state reaction technique, and they were characterized by using X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), elemental mapping, photoluminescence excitation and emission, decay curves, CIE chromaticity coordinates, internal quantum efficiency (IQE), and temperature-dependent emission spectra . The CLT host crystallized in a monoclinic structure with space group of P2 1 /n, and it contained an octahedral site of TaO 6 for Mn 4+ doping. Impressively, under 351 ultraviolet light excitation these CLT: x Mn 4+ phosphors exhibited bright deep-red emissions around 682 nm with CIE chromaticity coordinates of (0.7272, 0.2728) and full width at half maximum (FWHM) of 25 nm. Notably, the optimal CLT:0.2%Mn 4+ sample possessed an IQE of 37% and good resistance to thermal quenching (I 423 K /I 303K = 47%). Considering the emission spectrum of CLT:0.2%Mn 4+ deep-red-emitting phosphors matched well with the absorption spectrum of phytochrome P FR , the as-prepared CLT:0.2%Mn 4+ phosphors showed great potential in plant growth LEDs.
研究领域:
材料科学
·
植物学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2022
·
IF 5.436
Chuqiao Wu,Shuting Zhang,Yuhui Zheng,Aiqi Wang,Qiming Zhao,Wenjie Sun,Wanqiang Liu,Chenggang Long,Qianming Wang
Treatment of sulfur dots with polyethylene glycol (PEG) has been an efficient way to achieve a high luminescence quantum yield, and such a PEG-related quantum dot (QD)-synthesis strategy has been well documented. However, the polymeric insulating capping layer acting as the “thick shell” will significantly slow down the electron-transfer efficiency and severely hamper its practical application in an optoelectric field. Especially, the employment of synthetic polymers with long alkyl chains or large molecular weights may lead to structural complexity or even unexpected changes of physical characteristics for QDs. Therefore, in sulfur dot preparation, it is a breakthrough to use short-chain molecular species to replace PEG for better control and reproducibility. In this article, a solvent-type passivation (STP) strategy has been reported, and no PEG or any other capping agent is required. The main role of the solvent, ethanol, is to directly react with NaOH, and the generated sodium ethoxide passivates the surface defects. The afforded STP-enhanced emission sulfur dots (STPEE-SDs) possess not only the self-quenching-resistant feature in the solid state but also the extension of fluorescence band toward the wavelength as long as 645 nm. The realization of sulfur dot emission in the deep-red region with a decent yield (8.7%) has never been reported. Moreover, a super large Stokes shift (300 nm, λex = 345 nm, λem = 645 nm) and a much longer decay lifetime (109 μs) have been found, and such values can facilitate to suppress the negative influence from background signals. Density functional theory demonstrates that the surface passivation via sodium ethoxide is dynamically favorable, and the spectroscopic insights into emission behavior could be derived from the passivation effect of the sulfur vacancy as well as the charge-transfer process dominated by the highly electronegative ethoxide layer.
研究领域:
材料科学
·
光学
·
理论化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）