JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
·
2025
·
IF 4.7
Wenfeng Yuan,Xianke Sun,Meng Wu
A phosphor that emits both white light and broad near-infrared (NIR) light is of significant interest across various fields, as it enables both visual inspection and NIR spectroscopic detection. In this study, we designed Dy 3+ /Cr 4+ codoped CaLuGaO 4 phosphors that emit both white light and broad NIR light ranging from 1100 nm to 1700 nm when excited at 450 nm. The white light is produced by the 4 F 9/2 → 6 H 15/2 , 6 H 13/2 , 6 H 11/2 transitions of Dy 3+ . The broad NIR light arises from the 3 T 2 to 3 A 2 transition of Cr 4+ . Additionally, energy transfer from Dy 3+ to Cr 4+ occurs in the Dy 3+ /Cr 4+ codoped CaLuGaO 4 phosphors, allowing for tunable ratios of white light to NIR light by varying the concentrations of Dy 3+ and Cr 4+ . A phosphor-converted light-emitting-diode was constructed by encapsulating the synthesized phosphors around a commercial blue LED chip, demonstrating potential applications in lighting sources and non-destructive spectral analysis.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2016
·Vol. 3
·期 8
·1082-1090
·
IF 4.532
Min Li,Xiaoyang Liu,Li Liu,Bing Ma,Benxian Li,Xudong Zhao,Wenming Tong,Xiaofeng Wang
A series of Yb3+/Tm3+ co-doped β-NaYF4 (β-NaYF4:Yb,Tm) crystals have been successfully synthesized via the molten salt synthesis (MSS) method. A unique strong green emission of Tm3+ was observed, which cannot be obtained by any other method. The red, green and blue (RGB) light emissions have been obtained simultaneously in the presence of a single activator (Tm3+). The influencing factors of crystal growth have been studied in detail, in order to understand the change of the transition probabilities of Tm3+. Subsequent studies indicate that the RGB light emissions of Tm3+ can be effectively tuned by varying the concentration of sensitizers (Yb3+ and Mn2+) and the reaction time. Consequently, the effective multicolor upconversion (UC) luminescence was obtained, especially a strong white light, which was not obtained in the β-NaYF4:Yb,Tm system earlier. To our knowledge, it is the first time that the UC properties in the β-NaYF4:Yb,Tm system have been investigated by altering the transition probabilities at the same energy level of Tm3+.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Rui Zhou,Xue-Ying Wu,Qi Zhao,Kai-Kai Liu,Lin Dong,Chong-Xin Shan
ZnO nanoparticles (NPs) have been synthesized by a facile one-step synthesis method, and the emission color of the ZnO NPs can be tuned from orange to yellow, green, blue-green and blue. These ZnO NPs were used as phosphors to fabricate UV-pumped white light-emitting diodes (WLEDs). The color rendering index of the WLEDs is (0.31, 0.33), which is close to the standard white emission. The WLEDs have high correlated color temperature (6532 K) and Commission International de L'Eclairage (90.4). These results indicated that the multi-colored ZnO NPs have great application potential in lighting and display.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Photonics Research
·
2021
·Vol. 2
·期 5
·2000161
·
IF 0
Bin Liu,Zheng Chen,Bo Chu,Ya-Ling Wang,Ning Li,Huinian Zhang,Yongzhen Yang,Shengliang Hu,Xing-Hong Zhang
Despite the advancements in synthetic methods, it is still challenging to prepare white light-emitting carbon dots for solid-state white light-emitting diodes (LEDs). Herein, the synthesis and characterization of a carbonized polymer dot (CPD) that emits white light in the solid state are presented. The reaction of an oxygen-rich precursor, trimethylolpropane tri(cyclic carbonate) ether, with nitrogen-rich melamine in an alcohol via a single-step solvothermal method affords CPDs with hydroxyurethane and CN groups. The morphology of the CPDs can be regulated by changing the reaction time. Transmission electron microscopy reveals structural evolution from flocculent polymers to dandelion-like and spherical particles with an increase in the carbonization time from 6 to 12 and 18 h, respectively. The dandelion-like CPDs exhibit a relatively high quantum yield of 7.5% in the solid state, which is ascribed to the abundant surface poly(hydroxyurethane) chains that restrict the aggregation-caused quenching of luminescence. It is proposed that multiple coexistent clusters generate different emission sites, thereby leading to white light emission. Loose clusters formed from hydroxyurethane and CN bonds, which have a low degree of conjugation, emit blue light, whereas compact clusters generated through interactions between the hydroxyurethane and CN bonds of poly(hydroxyurethane) and carbon cores emit yellow light.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
CRYSTENGCOMM
·
2020
·Vol. 22
·期 41
·6911-6919
·
IF 3.117
Dingyi Shen,Yini Mao,Jun Yang,Lu Cao,Juntao Ning,Shanshan Hu
In this work, uniform and monodisperse Sr2YF7 spheres were successfully synthesized via a facile one-step hydrothermal route without employing any surfactant. Particularly, a well-defined morphology of Sr2YF7 crystals ranging from spherical to octahedral shape was first achieved by adjusting the pH values. In addition, the spherical products doped with 6% Ln3+ (Ln = La, Ce, Pr, Sm, Gd, and Dy) show different sizes ranging from 300 to 600 nm. The Sr2YF7 crystals also exhibit excellent multicolor DS/UC luminescence properties after doping with different Ln3+ ions. Energy transfer from Tb3+ to Eu3+ was observed in Sr2YF7 crystals; the Sr2YF7:Dy3+ crystals showed nearly white light emission under UV excitation; Sr2YF7:Yb3+/Er3+/Tm3+ crystals could produce pure white light with a CIE color coordinate of (0.3123, 0.3005) by controlling the doping concentrations of Er3+ and Tm3+ ions under 980 nm excitation. The as-prepared phosphors may potentially serve as light, color displays and markers in biological imaging.
研究领域:
材料科学
·
光学
·
生物成像
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 2
·1-9
·
IF 5.479
Sun Huaijing,Mei Qingsong,Shikha Swati,Liu Jinliang,Zhang Jing,Zhang Yong
The authors describe the use of white-light emitting upconversion nanoparticles (WL-UCNPs) for visual detection of the pesticide thiram. The method is demonstrated to undergo a better discernable color change upon target binding. The WL-UCNPs are modified with the lead(II)-dithizone complex which acts as the energy acceptor and recognition unit. This leads to quenching of the blue (475 nm) and green (545 nm) emissions of the WL-UCNPs, while the red emission (650 nm) remains unaffected. Upon addition of thiram, the quenched emissions are recovered, with a linear signal increase in the range from 2 nM to 20 nM of thiram and a limit of detection of 0.26 nM. The nanoprobe was further integrated into a test paper for visual detection. The concentration-dependent color change that varies from red to cyan and bluish violet and then to white can be visually distinguished.
Schematic presentation of a white-light emissive upconversion nanoparticle based test paper for color-discernable detection of the pesticide thiram. The test stripe exhibits a concentration-dependent color variation spanning from red, cyan, to bluish violet, and at last to white.
研究领域:
分析化学
·
环境科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2019
·
IF 2.291
Ping Xiao,Song Ye,Huazhen Liao,Yanling Shi,Deping Wang
The ability to increase the emission intensity and turn the emission color of upconversion nanocrystals (NCs) will greatly enhance their application scopes. In this research, the sub-10 nm pure β-NaYF 4 : Yb 3+ /Tm 3+ /Ho 3+ core NCs were prepared by using sodium oleate (NaOA) as sodium source instead of the traditional NaOH, based on which the β-NaYF 4 :Yb 3+ /Er 3+ @NaYF 4 core-shell NCs were successfully obtained with seed-mediated growth method. The spectral measurement and the calculated CIE color coordinates revealed that the growing of inert NaYF 4 shell on the active NaYF 4 : Yb 3+ /Tm 3+ /Ho 3+ core NCs can not only effectively increase the upconversion emission intensity, but also realize extended tunable emission from blue to orange by turning Ho 3+ concentration, and a strong white light emission with chromaticity coordinates of (0.32, 0.33) can be obtained in the NaY 0.77 F 4 :0.2Yb 3+ /0.01Tm 3+ /0.02Ho 3+ @NaYF 4 core-shell NCs. Furthermore, the extended color tunability and efficient white white-light generation in the core-shell NCs were demonstrated by NCs-PMMA nanocomposites under 980 nm excitation. The results suggested that the β-NaYF 4 :Yb 3+ /Er 3+ @NaYF 4 core-shell NCs have promising applications in optoelectronic devices such as light emitting diode and three-dimensional display.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL PAPERS
·
2023
·Vol. 77
·期 8
·4633-4642
·
IF 2.2
Li Rongfa
Animated displays and fluorescent devices are researched for fashion media. In this work, perovskite nanocrystals (PNCs)/copolymer composite with high luminescent intensity and stability was prepared. Two composites bearing PNCs (various polymer matrices) were fabricated via drop-coating method. Micro-/nano-structure, crystallization, and light absorption/photoluminescence (PL) traits of PNCs were characterized. PNCs/poly(methyl methacrylate- co -butyl acrylate) (PMMA- co -PBA) composite shows a better film-forming property than PNCs/polymethyl methacrylate (PMMA) composite. PL-emission properties of PNCs/copolymer composite are comparable to PNCs, including the maintained emission wavelength (~ 521 nm) and narrow emission half-peak width. For high fluorescent stability after air/ultraviolet aging, PNCs/copolymer composite is superior to PNCs and PNCs/homopolymer composite. PNCs/copolymer composite shows a PL intensity of ~ 90% after air aging for 40 days (~ 80% after ultraviolet aging for 120 h). Luminescent film devices via PNCs/copolymer composite were studied, and effective green-/white-light emissions were achieved. The present white-light emission is close to the international standard. This work might enable a large-scale preparation of quantum dots/polymer composites for luminescent devices.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
Small Structures
·
2024
·
IF 13.9
Xinrui Chen,Xing Han,Caixia Zhang,Xue Ou,Xiaoli Liu,Junhua Zhang,Wei Liu,Arthur J. Ragauskas,Xueping Song,Zhanying Zhang
Light-emitting diodes (LEDs) are widely used in lighting and display applications. Carbon quantum dots (CQDs), which have high biocompatibility, high resistance to photobleaching, and full-spectrum luminescence, have inherent advantages as fluorescent materials for LED devices. Herein, multicolor CQDs are prepared by a new reagent engineering strategy due to the difference of effective conjugate length and the surface electron-withdrawing groups of CQDs. White CQDs are realized by mixing blue, green, and red CQDs proportionally. Then, the aggregation-caused quenching phenomenon of CQDs is suppressed through the hydrogen-bonding network of cellulose nanofibrils (CNFs). Multicolor fluorescent films are prepared from CQDs and CNFs by simple mixing and casting methods. Finally, thin-film encapsulation based on the photosensitive resin ABPE-10 coating can be realized and rapidly assembles into fluorescent films with different light-emitting colors into LED devices, leading to have superior thermal performance compared with conventional LEDs. White LEDs have excellent white-light illumination performance, with Commission Internationale de L’Eclairage color coordinates of (0.33, 0.37), a correlated color temperature of 5688 K, and a color rendering index of 86. This strategy provides a convenient and scalable pathway for low-cost, environmentally friendly, and high-performance CQDs-based LEDs.
研究领域:
材料科学
·
光学工程
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2015
·
IF 6.723
Qi Zhao,Junting Li,Xiaoqian Zhang,Zhengping Li,Yanli Tang
We designed and synthesized a novel oligo(thiophene ethynylene) (OTE) to investigate the antibacterial activities against Gram-positive (Staphylococcus aureus and Staphylococcus epidermidis) and Gram-negative (Ralstonia solanacearum and Escherichia coli) bacteria in vitro by photodynamic therapy (PDT). Notably, OTE presents broad-spectrum and greatly high antibacterial activities after white light irradiation at nanogram per milliliter concentrations. The half inhibitory concentrations (IC50) values obtained for S. aureus, S. epidermidis, E. coli, and R. solanacearum are 8, 13, 24, and 52 ng/mL after illumination for 30 min, respectively, which are lower than that of other PDT agents. Interestingly, OTE shows the specific and very strong dark killing capability against S. aureus at the concentration of 180 ng/mL for 30 min, which is the highest efficiency biocide against S. aureus without the need of irradiation to date. The antibacterial mechanism investigated demonstrated that reactive oxygen species or singlet-oxygen generated by OTE kills bacteria irreversibly upon white light irradiation, and OTE as a v-type oligomer exerts its toxicity directly on destroying bacterial cytoplasmic membrane in the dark. Importantly, the OTE shows no cell cytotoxicity and excellent biocompatibility. The results indicate that it is potential to provide versatile applications in the efficient control of pathogenic organisms and specific application for killing S. aureus.
研究领域:
生物化学
·
微生物学
·
药物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2021
·
IF 3.599
Cen Zhang,Xiaonan Zhu,Fei Gao,Liu Yang,Weizhen Liu
The development of wavelength adjustable electrically driven panchromatic display light-emitting devices (LEDs), a future direction for lighting sources, still seems necessary because of great development prospects and practical significance. Herein, perovskite quantum dots (QDs) of CsPbBr 3 and CsPbI 3 with multi-color luminescence feature were employed into n-ZnO/p-GaN nano-heterojunction LEDs. A thin polystyrene cover layer was intentionally inserted between CsPbBr 3 and CsPbI 3 to prevent the undesired halogen anion-exchange reaction. A color-tunable electroluminescence (EL) could be achieved by changing the molar ratio of these two types of perovskite QDs. By further optimizing the molar ratio between CsPbBr 3 and CsPbI 3 , that is, the evolution of the share of red, green and blue-violet luminescence in EL spectra, a stable white light emission was obtained. The current research not only achieves multi-color EL emissions in a three-dimensional nano-architecture, but also proposes an effective and clever strategy for preparing and developing single-chip white LEDs.
研究领域:
材料科学
·
光学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2023
·Vol. 13
·期 37
·25681-25690
·
IF 3.9
Jie Liang,Ting Fan,Jian-tao Lü,Tianjie Guan,Ting-ting Deng,Bangyun Xiong
NaGdF4:Ce,Eu,Tb nanocrystals were successfully prepared by a one-step hydrothermal method with Ce3+ ions as sensitizers, Eu3+ and Tb3+ ions as activators, and polyethylenimine (PEI) as surfactants. Color-adjustable fluorescence emission was achieved by the energy transfer effect between rare earth ions. Blue fluorescent carbon quantum dots (CDs) with a double UV response under 254 nm and 365 nm excitation were synthesized by a one-step hydrothermal method. A hydrophilic NaGdF4:Ce,Eu,Tb/CD composite ink was prepared by an easy physical mixing method. Because of the electrostatic self-assembly effect, the color adjustable luminescence was achieved in a few seconds, and the white light emission with color coordinates of (0.32, 0.32) was obtained. A dual-mode luminescence anti-counterfeiting pattern was designed and achieved by excitation with ultraviolet light at 254 nm and 365 nm.
研究领域:
材料科学
·
光学
·
纳米技术
✓ 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）