CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Wenwei Lai,Chuanli Wu,Xiuxun Han
All-inorganic perovskite CsPbBr 3 shows great potential in optoelectronic device applications due to their excellent optoelectrical properties. However, its practical use is still dauntingly plagued by the poor stability. Recently, its derivatives Cs 4 PbBr 6 and CsPb 2 Br 5 featured with good stability and the versatility in crystal structure have emerged as promising alternatives. Nevertheless, synthesizing such a series of perovskites through a facile, scalable, and high-yield method is challenging, and their luminescence mechanisms are still elusive. Herein, we reported a facile and rapid method for continuous synthesis of Cs x Pb y Br z -based perovskites (including Cs 4 PbBr 6 , CsPbBr 3 /Cs 4 PbBr 6 , CsPbBr 3 , CsPbBr 3 /CsPb 2 Br 5 , CsPb 2 Br 5 ) via a microfluidic system. The transformations of different dimensional perovskite nanocrystals were realized by simply adjusting the precursor flow rate. CsPbBr 3 /Cs 4 PbBr 6 and CsPbBr 3 /CsPb 2 Br 5 composite nanocrystals exhibited bright emissions in their solid forms, where CsPbBr 3 nanocrystals uniformly embedded in Cs 4 PbBr 6 or CsPb 2 Br 5 matrix. Simultaneously, strong green fluorescence exclusively from CsPbBr 3 nanocrystals was detected and related energy transfer in composite nanocrystals was further investigated. Finally, the highly stable CsPbBr 3 /Cs 4 PbBr 6 nanocrystals were used for the construction of WLED with a wide color gamut of 131% NTSC. This work provides a novel path for large-scale and controlled synthesis of the ternary Cs-Pb-Br materials for specific light-emitting applications.
研究领域:
材料科学
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纳米科技
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光学工程
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无机化学
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半导体物理
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Z.H. Xu,C. Wang,X.Z. Xiong,W.B. Dai
Borate-based phosphors, as a critical class of luminescent materials, have garnered significant attention due to their stable crystal structures, wide bandgaps, excellent thermal stability, and robust spectral tunability, making them essential components in white light-emitting diodes ( w LEDs) technologies. In this work, a high-symmetry Ba 3 Y 2 B 6 O 15 (BYB) phosphor co-doped with Bi 3+ , Tb 3+ , Eu 3+ , and Lu 3+ was synthesized via a multi-step sol-gel method. Different photoluminescence (PL) behaviors of Bi 3+ , Tb 3+ and Eu 3+ in BYB were systematically revealed. By modulating the PL spectrum via energy transfer (ET) from Bi → Tb → Eu, ‘cool’ white-light emission was achieved. A strategy of replacing Y 3+ with Lu 3+ was adopted to adjust the crystal field splitting and symmetry. This modification broadens the blue light coverage range in Bi 3+ PL, increases the hypersensitive transition of Eu 3+ ( 5 D 0 → 7 F 2 ), increase the intensity of red emission. They achieved their optimal balance ultimately. The improved structural compactness and rigidity reduced electron-phonon coupling effects, endowing the phosphor with superior chemical/thermal stability. Finally, a high-performance phosphor-converted w LED (pc- w LED) device with chromaticity coordinates of (0.361, 0.358), a luminous efficacy (LE) of 95.2 lm/W, was fabricated by integrating the optimized BYB: Bi/Tb/Eu/Lu phosphor with a UV LED chip using remote ‘cap’ packaging, demonstrating exceptional performance.
研究领域:
材料科学
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光学工程
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无机化学
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固态照明
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功能材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Peiyuan Zhuang,Cong He,Huanlin Lv,Chunwen Ye,Yanjie Zhang,Bing Li
Inorganic perovskite quantum dots (PQDs) have great potential in display, lighting and other fields because of their high optical properties, narrow fluorescence emission half-peak width and convenient synthesis. However, the large Stokes shift (more than 155 nm) of KCsPbBr 3 PQDs results in more energy loss, and the maximum excitation peak is normally located at near-ultraviolet (NUV) region (∼365 nm), greatly limiting its application in lighting and displays based on blue light emitting diodes (LEDs). Herein, KCsPbBr 3 PQDs in lithium disilicate glass powders with a super broad excitation band in the range of 330–450 nm and narrow Stokes shift of ∼67 nm has been developed. Lithium disilicate glass with excellent mechanical properties are introduced as rigid armor to keep CsPbBr 3 PQDs from thermal and moisture attack, even maintaining the average particle size of ∼2.4 nm after high temperature calcination (600 °C). Interestingly, photoluminescence excitation spectrum of KCsPbBr 3 PQDs glass calcined at 600 °C presents which is entirely consistent with the emission wavelength of NUV and blue LEDs. In addition, the photoluminescence intensity of KCsPbBr 3 PQDs in lithium disilicate glass powders increases firstly and then decline sharply after calcination 600 °C, which exhibits with a narrow full width at half peak (FWHM) of ∼20 nm. The KCsPbBr 3 PQDs glass exhibits ultrahigh stable properties and maintains the photoluminescence emission intensity even soaked in deionized water for more than 85 days, indicating a great potential in fields such as green or white light lighting and fingerprint recognition.
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2023
·Vol. 16
·期 20
·6667
·
IF 3.4
Yukun Li,Svenja Hanson,Cheng Heng Pang,Peng Lyu,Jun Jiang
In order to attain phosphor ceramics with a high Color-Rendering Index (CRI), samples with the composition of Y0.997−xRexCe0.003)3(Al0.9748Mn2+0.024Cr3+0.0012)5O12(Rex= 0, Gd0.333, Gd0.666, Gd0.997, Tb0.333, Tb0.666, Tb0.997and Lu0.997were prepared by solid-state reaction and vacuum sintering, and exhibited potential for high-quality, solid-state lighting. Doping with Cr3+and Mn2+effectively enhanced the red component of Ce3+spectra through the intense energy transfer from Ce3+ions to Mn2+/Cr3+ions. The crystal field splitting of [GdO8] and [TbO8] was more extensive than that of [YO8], causing a massive redshift in the Ce3+emission peaks from 542 to 561 and 595 nm, while [LuO8] had an opposite effect and caused a blueshift with a peak position at 512 nm. White LED devices incorporating Ce/Mn/Cr: (Gd0.333Y0.664)3Al5O12phosphor ceramic exhibited a high CRI of 83.97, highlighting the potential for enhancing the red-light component of white LED lighting.Keywords:garnet phosphor;laser lighting;full spectrum;spectral modulation;Ce/Mn/Cr: (Re,Y)3Al5O12
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
Xiangyu Chen,Juanjuan Yao,Bin Xia,Jingye Gan,Naiyun Gao,Zhi Zhang
The influence of pH and dissolved oxygen (DO) on the degradation of ofloxacin (OFX) in water by UVA-LED/TiO 2 nanotube arrays photocatalytic fuel cell (UVA-LED/TNA PFC) was investigated. The degradation pathway depended on the location of OFX frontier orbital with different ionization states and the role of reactive oxidative species (ROSs) played with varied pH and DO values. In presence of DO, the quencher tests revealed that O 2 − played a key role at pH 3.0, 7.0 and 11.0, while OH made its greatest contribution at pH 3.0 and the effect of h + was largely inhibited at pH 11.0. Hydroxylation for cationic OFX was more significant, while demethylation and piperazinyl ring oxidation for anionic OFX occurred more quickly compared to other forms. Besides, zwitterionic OFX underwent decarboxylation and combination of demethylation & hydroxylation more easily. Much higher power generation was observed in presence of DO at pH 7.0, probably due to the enhanced adsorption of OFX on the TNA, and DO could amplify the electric potential between the two electrodes. The degradation efficiencies were almost the same in presence or absence of DO, but the pathways were different and e- aq may replace O 2 - as the leading ROSs in absence of DO.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF ANALYTICAL CHEMISTRY
·
2022
·
IF 1.193
Yuzhe LI,Hui ZENG,Jin XU,Yan LI,Lishan ZHANG,Ying LIANG,Min ZHANG
A gas-phase absorption detector (GPAD) was developed using a surface-mount 235 nm light-emitting diode (LED) as the light source. Modules for housing the LED and photodiode were three-dimensional printed. A stainless-steel tube was used as the detection cell. To perform long path absorption detection, a fused silica full-ball lens (5 mm diameter) was employed to collimate the light produced by the UV-LED with a viewing angle of 120°. The light attenuation coefficient ( α b ) was measured to be 0.025±0.001 cm −1 . The optimum path length with the maximum signal-to-noise ratio was obtained at ca. 80 cm. This result agreed with the theoretical calculation for optimum path length, i.e., 2/ α b . The GPAD was coupled with an automated analysis system and applied to detect nitrite in water. The automated system added citric acid and ethanol into a water sample, and nitrite was converted to gaseous nitrous acid (HONO), which has a strong absorption at 235 nm. The produced HONO was purged with air, followed by water removal, and then detected with the GPAD. The method was used to detect nitrate and total dissolved nitrogen (TDN) in water as well. Nitrate was reduced to nitrite through a photo-induced reaction with a conversion efficiency of ca. 60%. TDN was converted to nitrate by using an alkaline persulfate digestion method, followed by photoreduction to nitrite, and detected by using the automated system. The limits of detection were 0.4 μM, 3.9 μM, and 6.7 μM (94 μg N/L) for nitrite, nitrate, and TDN, respectively.
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2022
·
IF 9.224
Lin Liu,Shanshan Peng,Lei Fu,Yuxuan Guo,Xia Sun,Liang Song,Junpeng Shi,Yun Zhang
Since the strong blue light from the conventional blue chip has negative effects on human health, near-ultraviolet (n-UV) white light-emitting diodes (W-LEDs) have been widely studied. However, the photoluminescence spectrum generated by tricolor (blue, green, and red) phosphors contains a notable cavity in the deep-blue region (400–430 nm), which reduces the color quality. In this work, we report a novel series of narrow-band deep-blue-emitting phosphors with strong n-UV excitation, Ln2Si2O7:Bi3+ (Ln = Gd, Y, Lu, Sc), and realize the tuning of emission from 422 to 403 nm via cationic substitution, which bridges the deep-blue gap. All of these phosphors are effectively excited by n-UV radiation at approximately 370 nm and exhibit narrow-band deep-blue emission with a full width at half-maximum (FWHM) < 50 nm. Among them, Sc2Si2O7:Bi3+ generates 403 nm deep-blue emission with a 38 nm FWHM under 372 nm n-UV excitation, with high luminescence intensity and excellent thermal stability. Finally, 365 nm n-UV-pumped phosphor-converted (pc) W-LED devices are fabricated by combining Sc2Si2O7:Bi3+ and commercially available phosphors, and they have a high color-rendering index (Ra) of 95.4 and a low correlated color temperature (CCT) of 3736 K. This result suggests that these phosphors have potential applications in full-spectrum warm white lighting.
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产品关联
DOI
高影响因子
Advanced Optical Materials
·
2020
·Vol. 8
·期 22
·2001037
·
IF 8.286
Dongjie Liu,Xiaohan Yun,Guogang Li,Peipei Dang,Maxim S. Molokeev,Hongzhou Lian,Mengmeng Shang,Jun Lin
Highly efficient cyan-emitting phosphor materials are indispensable for closing the cyan gap in spectra of the traditional phosphor-converted white light-emitting diodes (WLEDs) to achieve high-quality full-spectrum white lighting. In this work, bright cyan-emitting Ca 3 Ga 4 O 9 (CGO):0.02Bi 3+ ,0.07Zn 2+ phosphor is developed to bridge the cyan gap. Such a Bi 3+ ,Zn 2+ codoping enhances the cyan emission of CGO:0.02Bi 3+ by 4.1 times due to the influence of morphology and size of phosphor particles, charge compensation and lattice distortion. Interestingly, codoping La 3+ ions into the current system can achieve a photoluminescence tuning of CGO:0.02Bi 3+ from cyan to yellowish-green by crystallographic site engineering. Besides, Bi 3+ –Eu 3+ energy transfer is successfully realized in CGO:0.02Bi 3+ ,0.07Zn 2+ , n Eu 3+ phosphors and the emission color tuning from cyan to orange is observed. The investigation of thermal quenching behaviors reveals that the incorporation of Zn 2+ and La 3+ improves the thermal stability of CGO:0.02Bi 3+ . Finally, CGO:0.02Bi 3+ ,0.07Zn 2+ ,0.10Eu 3+ phosphor is employed to obtain a single-phased warm WLED device. A full-spectrum WLED device with remarkable color rendering index (Ra) of 97.4 and high luminous efficiency of 69.72 lm W −1 is generated by utilizing CGO:0.02Bi 3+ ,0.07Zn 2+ phosphor. This result suggests the important effect of CGO:0.02Bi 3+ ,0.07Zn 2+ phosphor on closing the cyan gap, providing new insights of cyan-emitting phosphors applied in full-spectrum white lighting.
研究领域:
材料科学
·
光学工程
·
固体物理
·
无机化学
·
光电子学
·
照明技术
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2020
·
IF 3.28
Zhiqin Zheng,Peizhang Xie,Panpan Yi,Jun Zhao,Lihong Liu,Facheng Yi
Nowadays, ultraviolet (UV) and blue converted phosphors have played a key role in the solid-state lighting field, and the white light is usually produced by mixing multiple phosphors. In this work, we report a type of UV converted single white phosphor, i.e. , Ba 9 La 2 Si 6 O 24 :Eu 3+ ,Bi 3+ .Various techniques, such as powder X-ray diffraction (XRD), scanning electron microscopic (SEM), photoluminescence (PL) spectra, and quantum efficiency (QE), have been used to characterize the samples. In Bi 3+ doped samples, upon excitation within the wavelength range of 250–380 nm can lead to three Bi 3+ emission bands ( i.e. , 358 nm, 415 nm, and 516 nm), but only one emission band peaking at 415 nm appears when the excitation wavelength exceeds 380 nm. Structural analysis and discussion on the PL intensity variation reveal there are three Bi 3+ luminescent centers at two different La 3+ sites and one Ba 2+ site. The Bi 3+ concentration-induced luminescent quenching is dominated by the d-d interaction. In view of the spectral overlap between the Bi 3+ emissions and the Eu 3+ excitation spectra , the energy transfer from Bi 3+ to Eu 3+ of the Ba 9 La 2 Si 6 O 24 :Eu 3+ ,Bi 3+ is studied, and it is dominated by a dipole-quadrupole ( d - q ) interaction. Moreover, upon excitation at 365 nm, the emissions broadly tuning from blue, white and to red are achieved by varying the Eu 3+ content. For the white Ba 9 La 2 Si 6 O 24 :Eu 3+ ,Bi 3+ sample, high temperature PL results show that it does not have severe degradation of emission intensity after increasing the temperature from 25 to 300 °C, exhibiting a good thermal stability . To show the potential application in the lighting fields, we fabricate a white light LEDs device by depositing this white phosphor on a 365 nm UV LED chip. As a result, the values, i.e. , a color rendering index (CRI) of 95, luminous efficiency of 80 lm/W, and color temperature (CT) of ~4215 K at chromaticity (0.382, 0.398), are achieved.
研究领域:
材料科学
·
发光材料
·
固态照明
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
ACS Applied Engineering Materials
·
2024
·
IF 0
Zongtao Li,Zelong Li,Jiasheng Li,Guanwei Liang,Yaoxing Song,Xinrui Ding
While the active camouflage approach based on thermochromic materials in the visible–infrared spectrum achieves camouflage effects, it suffers from issues such as temperature-dependent color change, limited color range, and color nonuniformity, which undermine its reliability and applicability. This paper presents a visible–infrared active camouflage device comprising light-emitting diodes with a photothermal-scattering hybrid structure (PSHS-LED camouflage device), which includes a flexible LED display array, a photothermal conversion layer, and a flexible scattering layer. Herein, the employed photothermal conversion layer made of graphite-infused polydimethylsiloxane (PDMS) functions to convert a portion of visible light into heat which is emitted in the form of infrared radiation. At the same time, the selective scattering layer made of porous poly(methyl methacrylate) (PMMA), in which the incident visible light will be diffusely propagated, whereas infrared light undergoes minimal scattering. Finally, a visible–infrared active camouflage device enabling independent control of visible-light and infrared imaging is obtained, ensuring effective camouflage in the visible–infrared detection domain. The manufactured PSHS-LED camouflage device exhibits a distinctly discernible infrared imaging effect when the infrared detector is sufficiently close, with a maximum temperature difference of 15 °C within the device. Meanwhile, the manufactured PSHS-LED camouflage device exhibits a wide color gamut (102% of the Adobe RGB gamut) and uniform display performance, offering a viable solution for visible–infrared active camouflage.
研究领域:
材料科学
·
光学工程
·
电子工程
✓ 已验证
DOI
ACS Applied Polymer Materials
·
2019
·
IF 0
Jiawei Liu,Jiahui Liu,Feiyang Ma,Jiguang Liu
Particles with circumstance-responsive conductivity have an appealing performance in constructing sensors. Here, “smart” conducting polyaniline-doped poly(styrene-co-N-isopropylacrylamide) composite spheres, i.e. PANI/P(St-NIPAM) particles, are reported. A series of PANI/P(St-NIPAM) particles can be prepared with different ratios of N-isopropylacrylamide to monomers, i.e. N/M ratios. With the improved N/M ratios in polymerization, the amount of polyaniline (PANI) incorporating into the produced particles increased, resulting in an enhanced conductivity. With the improved N/M ratios, the hydrodynamic diameters of PANI/P(St-NIPAM) particles increased at a low temperature, whereas they decreased at a high temperature; resulting in the enhanced volume-change ability with the increasing poly(N-isopropylacrylamide) (PNIPAM) content in particles. Depending on the temperature-induced volume change, these particles exhibit “smart” conductivity in a homemade device, in which these particles can be used as a temperature-responsive conducting medium to construct an “on–off” circuit, and the switch of an LED lamp can be triggered by temperature. These particles with the smart conducting property provide wide potential applications in sensors, microelectronics, energy storage, and other fields.
研究领域:
材料科学
·
传感器技术
·
高分子化学
✓ 已验证
DOI
OPTICAL MATERIALS
·
2024
·
IF 3.8
Qilin Yu,Jingxiang Liu,Pengjun Zhang,Shuwei Hao,Chongqiang Zhu,Chunhui Yang
A novel red phosphor BaY 4 Si 3 O 13 :Eu 3+ (BYSO:Eu 3+ ) was designed and prepared through a high-temperature solid-phase method in this work. It was found that the addition of Li 2 CO 3 in the synthesis process could significantly decrease the sintering temperature and increase the intensity and purity of red emission, as more lower symmetry sites were occupied by Eu 3+ . The optimum preparation conditions of BYSO:Eu 3+ were obtained as sintering at 1350 °C for 3h with the doping of 18% Eu 3+ and 5% Li 2 CO 3 . The CIE chromaticity coordinate was (0.636,0.362) and color purity reached 91.56% at room temperature, and 53.93% of the initial PL intensity could be retained when the temperature rose up to 453 K. The results showed that BYSO:Eu 3+ had greatly potential application in white LED deriving from the great red emission.
研究领域:
材料科学
·
光电技术
·
发光材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）