OPTICAL MATERIALS
·
2024
·
IF 3.8
Yanting Liu,Qiumei Li,Lili Meng,Qi Pang,Yanzhu Wang,Hua Yao,Qian Chen
The emergence of near-infrared (NIR) luminescence from lanthanide (Ln 3+ ) ions doped lead-free Cs 2 AgInCl 6 double perovskites (DPs) has garnered significant attention due to its extensive range of potential applications. Unfortunately, they still suffer from weak NIR emission due to the inherent wide band gap of DPs resulting in inefficient energy transfer from the host to Ln 3+ . Herein, Bi 3+ can act as the sensitizer to activate Ho 3+ emission and reduce the excitation energy in Cs 2 AgInCl 6 : Ho. Under 400 nm excitation, Bi 3+ co-doped Cs 2 AgInCl 6 : Ho shows 39 times and 21 times higher emission intensity than Cs 2 AgInCl 6 : Ho in Visible and NIR. As a result, a photoluminescence quantum yield of 18.63 % ranging from 800 to 1600 nm can be obtained. Finally, by coupling a Bi-doped sample with a commercial near-ultraviolet LED chip (395 nm), a compact Vis-NIR ultrawideband light source was prepared, which has promising applications in multifunctional illumination and night vision.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Hongshi Zhang,Jiyou Zhong,Fu Du,Lei Chen,Xiaoli Zhang,Zhongfei Mu,Weiren Zhao
Broad-band near-infrared (NIR) phosphors are essential to assembling portable NIR light sources for applications in spectroscopy technology. However, developing inexpensive, efficient, and thermally stable broad-band NIR phosphors remains a significant challenge. In this work, a phosphate, KAlP2O7, with a wide band gap and suitable electronic environment for Cr3+ equivalent substitution was selected as the host material. The synthesized KAlP2O7:Cr3+ material exhibits a broad-band emission covering 650–1100 nm with a peak centered at 790 nm and a full width at half-maximum (fwhm) of 120 nm under 450 nm excitation. The internal quantum efficiency (IQE) was determined to be 78.9%, and the emission intensity at 423 K still maintains 77% of that at room temperature, implying the high efficiency and excellent thermal stability of this material. Finally, a NIR phosphor-converted light-emitting diode (pc-LED) device was fabricated by using the as-prepared material combined with a 450 nm blue LED chip, which presents a high NIR output power of 32.1 mW and excellent photoelectric conversion efficiency of 11.4% under a drive current of 100 mA. Thus, this work not only provides an inexpensive broad-band NIR material with high performance for applications in NIR pc-LEDs but also highlights some strategies to explore this class of materials.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2024
·
IF 8
Qiaoling Chen,Litian Lin,Chang Ji,Chang-Kui Duan
The unintentional incorporation of various unknown trace amounts of impurities poses challenges and controversies in identifying luminescent mechanisms of certain systems. A common approach to confirm or exclude the involvement of a certain activation center is to monitor the changes in luminescence by intentionally doping the inferred species into the crystal. Here, an intriguing luminescent phenomenon resulting from the hidden interplay between the dopants and trace impurities, is presented. In alkaline-earth stannate perovskites, near-infrared luminescence is observed. By combining density-functional calculations with the well-designed doping and codoping experimental strategies, the mechanisms behind this anomaly is successfully uncovered. It originates from the stabilization of Cr 3 + by codopants such as Bi and rare-earth (RE) ions, acting as electron donors. The luminescence is almost unobservable when chromium is doped alone, and thus the traditional identification method does't work. This work emphasizes the important role of trace impurity in materials, especially the subtle change of valence state of trace impurity upon doping, which provides enlightening insights and prompts reassessments of numerous reported anomalous luminescent phenomena.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2024
·
IF 5.2
Sihan Yang,Xuyan Xue,Feng Jiang,Liang Dong,Qi Zhu,Xuejiao Wang,Ji-Guang Li
The emission wavelength of current near-infrared phosphors activated by Cr 3+ is generally smaller than 900 nm in near-infrared (NIR) I region, and it is extremely challenging and is of great practical significance to realize emission towards NIR-II region. In this study, a novel Cr 3+ excited KSrScSi 2 O 7 silicate broad-band phosphor was prepared using the traditional solid-state method. Cr 3+ resides in a weak crystal field in the KSrScSi 2 O 7 lattice and exhibits broad-band near-infrared emission at 984 nm, longer than those of most Cr 3+ activated phosphors, under 493 nm blue light excitation. This is due to the strong charge polarization caused by the unique local coordination environment of the silicate matrix, which leads to a reduction in the crystal field splitting energy of the [ScO 6 ] octahedron where Cr 3+ is located and the downward shift of the 4 T 2 energy level. The optimal doping concentration of Cr 3+ is found to be 2 mol%, and the quenching mechanism is dipole-dipole interaction. Compared to the phosphors with similar emission wavelengths ( λ em > 900 nm), KSrScSi 2 O 7 :Cr 3+ demonstrates outstanding advantages in various aspects of luminescent performance. The fabricated phosphor-converted light-emitting diode (pc-LED) is shown to have the potential for night vision and non-invasive imaging. Novel application of KSrScSi 2 O 7 : x Cr 3+ as stable green ceramic pigments is also explored. The KSrScSi 2 O 7 : x Cr 3+ powders show a bright yellowish green appearance, and the KSrScSi 2 O 7 :0.02Cr 3+ typical composition has chromaticity values of L* = 82.73, a* = –8.53, b* = 7.97. Remarkably, the glazing samples using KSrScSi 2 O 7 : x Cr 3+ as pigments well retain the bright color after 1200 °C sintering in different atmospheres. Therefore, multi-functional applications of KSrScSi 2 O 7 : x Cr 3+ for near-infrared spectroscopy and as ceramic pigments are achieved in this work.
研究领域:
材料科学
·
光学
·
陶瓷科学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2023
·
IF 3.9
Yihao Xu,Li Luo,Weiren Zhao,Wei Zhang,ZhengFa Hu
Developing novel broadband near-infrared (NIR) phosphors is crucial to promote NIR phosphor-converted light emitting diodes (pc-LEDs) development. In this paper, a novel multifunctional near-infrared phosphor, SrGa 4 O 7 :Cr 3+ , Yb 3+ , was synthesized by the conventional high-temperature solid-state method. The emission band of the material spans from 650 nm to 1100 nm. Despite the predominance of four-coordinate and five-coordinate sites within the SrGa 4 O 7 (SGO) lattice, the incorporation of Cr 3+ ions induces distortion in the Ga–O tetrahedra, resulting in an octahedral environment for Cr 3+ . Under blue light excitation, the Cr 3+ ions exhibit an ultra-wide emission band (650–900 nm) with a Full Width at Half Maximum (FWHM) of 131 nm. Furthermore, energy transfer from Cr 3+ to Yb 3+ was achieved in SrGa 4 O 7 :Cr 3+ , Yb 3+ , and the incorporation of an optimal quantity of Yb 3+ co-dopant yielded a significantly enhanced and extraordinarily broad spectrum from 600 to 1100 nm. Moreover, Yb 3+ -codoping improves the thermal stability due to the energy transfer from Cr 3+ to more thermally stable Yb 3+ emitters, and the integrated intensity of SrGa 4 O 7 :Cr 3+ , Yb 3+ at 300 K was 74% of that at room temperature. Based on these findings, a blue-light-excited NIR pc-LED was encapsulated. The forward voltage and intensity of the LED remained almost constant after 500 h of thermal aging at high temperatures, indicating its particular reliability in NIR pc-LED applications. The results show that SrGa 4 O 7 :Cr 3+ , Yb 3+ phosphors have great potential in ultra-wideband NIR pc-LED applications.
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
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2023
·
IF 4.4
Kang Cheng,Xinyue Liu,Qin Lu,Dongni Wu,Weichao Huang,Chaoyong Deng
Cr 3+ -free near-infrared (NIR) phosphors are currently gaining significant attention in various application fields. A novel Fe 3+ -activated LiAlO 2 NIR phosphor was successfully synthesized by high-temperature solid-state method. Under excitation of 391 nm and 467 nm, the phosphor emits near-infrared light with wavelengths ranging from 600 to 850 nm. The emission bands with peaks at 725 nm correspond to the transition from 4 T 1 ( 4 G) to the ground state energy level 6 A 1 ( 6 S). The optical band gap of LiAlO 2 was calculated using Density Function Theory (DFT) and diffuse reflectance spectrum, respectively. The thermal stability of the sample was measured under 391 nm and 467 nm excitation, showing that the emission intensity at 413 K is 55.3 % and 52.4 % of the emission intensity at room temperature .
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Lanjiao Li,Ying Chen,Rongfei Wei,Siyu Guo,Xiangling Tian,Fangfang Hu,Hai Guo
Near-infrared phosphor-converted light-emitting diodes (NIR pc-LEDs) are playing an increasingly important role in the spectroscopy technology fields. Developing high-performance NIR-emitting phosphors is of immense significance for advancing NIR pc-LEDs. Herein, the approach of cationic substitution of Ca 2+ by Mg 2+ was designed in Ca 4 ZrGe 3 O 12 :Cr 3+ . Remarkably enhanced NIR emission and strikingly improved thermal stability are realized. The luminescence intensity at 423 K compared with that of room temperature ascends from 45.67 % to 72.81 %. Moreover, the representative sample was assembled to a NIR pc-LED with favorable output power and photoelectric conversion efficiency by combining a commercial 470 nm blue chip. The packaged LED demonstrates the feasibility of practical applications in night vision, biological imaging, and fruit detection. The above findings verify the potential prospect of Ca 4- x Mg x ZrGe 3 O 12 :Cr 3+ phosphor for the utilizations in NIR light sources.
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
Journal of Materials Chemistry B
·
2015
·Vol. 3
·期 37
·7449-7456
·
IF 4.726
Xiang Li,Qiuhong Zhang,Zeeshan Ahmad,Jie Huang,Zhaohui Ren,Wenjian Weng,Gaorong Han,Chuanbin Mao
750–850 nm (NIR I) and 1000–1400 nm (NIR II) in the near infrared (NIR) spectra are two windows of optical transparency for biological tissues with the latter capable of penetrating tissue deeper. Monitoring drug release from the drug carrier is still a daunting challenge in the field of nanomedicine. To overcome such a challenge, we propose to use porous Nd3+-doped CaTiO3 nanofibers, which can be excited by NIR I to emit NIR II light, to carry drugs to test the concept of monitoring drug release from the nanofibers by detecting the NIR II emission intensity. Towards this end, we first used electrospinning to prepare porous Nd3+-doped CaTiO3 nanofibers by adding micelle-forming surfactant Pluronic F127, followed by annealing to remove the organic component. After a model drug, ibuprofen, was loaded into the porous nanofibers, the drug release from the nanofibers into the phosphate buffered saline (PBS) solution was monitored by detecting the NIR II emission from the nanofibers. We found that the release of the drug molecules from the nanofibers into the PBS solution triggers the quenching of NIR II emission by the hydroxyl groups in the surrounding media. Consequently, more drug release corresponded to more reduction in the intensity of the NIR II emission, allowing us to monitor the drug release by simply detecting the intensity of NIR II from the nanofibers. In addition, we demonstrated that tuning the amount of micelle-forming surfactant Pluronic F127 enabled us to tune the porosity of the nanofibers and thus the drug release kinetics. This study suggests that Nd3+ doped CaTiO3 nanostructures can serve as a promising drug delivery platform with the potential to monitor drug release kinetics by detecting the tissue-penetrating NIR emission.
研究领域:
纳米医学
·
生物材料
·
光学成像
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Hengjuan Deng,Xinxin Han,Juan Wang,Dongxi Liu,Bingsuo Zou
Near-infrared (NIR) light source technology has been integrated into mobile devices with the advantage of portability to provide efficient analysis in many fields. Among them, NIR light in the 850 nm band has attracted much attention due to its unique advantages. In this study, an ultra-broad NIR emission from 700 to 1100 nm with the peak at 839 nm and full width at half-maximum (FWHM) of 151 nm is achieved in a novel tetra-fluoride RbAlF4:Cr 3+ excited by 465 nm blue light, exhibiting a relatively longer emission wavelength and wider FWHM compared with the reported Cr 3+ -doped fluoride phosphors. In-depth research on its crystal structure reveals that Cr 3+ is in a weak crystal field with a distorted octahedral environment, coupled with a strong electron-phonon coupling effect, which prompts the phosphor to exhibit long-wavelength and broad NIR light characteristics. However, these reasons also lead to relatively moderate internal quantum efficiency and thermal stability. Finally, a NIR phosphor-converted light-emitting diode (NIR pc-LED) was fabricated by combining this phosphor with a commercial blue chip, which shows great potential in non-destructive testing, night-vision observation, and biomedical imaging. This work provides new insights into the design of long-wavelength broadband fluoride phosphors.
研究领域:
材料科学
·
光学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Optical Materials
·
2022
·
IF 0
Hongshi Zhang,Chaojie Li,Jiyou Zhong,Jun Wen,Weiren Zhao
The near-infrared (NIR) phosphor-converted light-emitting diode (pc-LED) is an emerging portable light source and has multifunctional applications based on spectroscopic technology. Nevertheless, it is still difficult to develop broadband NIR materials with strong resistance toward thermal quenching. In this work, a thermally robust broadband NIR phosphor NaGaP2O7:Cr3+ was reported, which has an emission peak located at 793 nm, and the emission spectrum covers 650–1100 nm with a full width at half-maximum (fwhm) of 115 nm. The emission intensity at 150 °C was surprisingly maintained as 85.45% of that at 25 °C, indicating an outstanding ability to resist thermal quenching. A systematic investigation of aspects such as structural rigidity, the band gap of the host, and the electron phonon coupling effect was carried out to understand the mechanism of thermally robust luminescence in this material. Finally, the NaGa0.94Cr0.06P2O7 NIR phosphor and 450 nm InGaN LED chip were combined to produce a prototype NIR light source. This device generates a NIR output power of 44.43 mW and a photoelectric conversion efficiency of 10.4% when driven at 150 mA, demonstrating a good performance of this material for practical applications.
研究领域:
材料科学
·
光学
·
固体物理
✓ 已验证
DOI
Inorganic Chemistry Frontiers
·
2024
·Vol. 11
·期 19
·6536-6548
·
IF 6.1
Wen Song,Kaiwen Zhang,Xiaoyi Dong,Liang Xu,Yongjin Li,Rui Hu,Zhaoyi Yin,Zhengwen Yang,Jianbei Qiu,Zhiguo Song
Realizing efficient long-wavelength near-infrared (NIR) emission of Cr3+ ions is still a challenge in spinel-based phosphors due to the limitations of strong crystal fields. Here, we propose three design strategies for obtaining weak crystal fields in spinel-type crystals, and report for the first time designed Cr-activated LiZnNbO4 (LZNO) crystals with unique weak crystal fields and application of an NIR enhancement strategy via heterotopic and heterovalent doping with trivalent rare earth ions. Under irradiation with 468 nm blue light, the phosphor presents ultra-wideband NIR emission centered at 800 nm covering the region of 650–1300 nm, which is attributed to the larger radius, high valence state of cations and the low symmetry of octahedral sites in the LZNO spinel. Supported by XRD refinement, XPS analysis, and density functional theory (DFT) calculation results, it was shown that when Er3+ ions are designedly doped with the Zn2+ sites of the spinel crystals, effective promotion of the valence state transformation of Cr4+ to Cr3+ in the LZNO:Cr3+ system is achieved by defect charge compensation, and this enhances the NIR emission by nearly 3 times. The results of this work not only enrich the material family of Cr3+-activated NIR emitting phosphors, but also offer a novel and simple method for improving the luminescence efficiency of Cr3+-activated phosphors.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2019
·
IF 2.687
Xiuna Tian,Hongjian Dou,Lingyuan Wu
Upconversion (UC) luminescent materials have received much attention due to their unique luminescent properties and potential applications in various fields. Yb 3+ /Tm 3+ codoped NaBiF 4 UC material has been successfully synthesized through a solvothermal method. With the excitation of 980 nm laser light, NaBiF 4 :Yb 3+ /Tm 3+ powder show strong UC luminescence. Especially, the near-infrared (NIR) UC emission band of NaBiF 4 :Yb 3+ /Tm 3+ centered at 800 nm is 49 times stronger than the blue emission band. The temperature-dependent UCL properties of NaBiF 4 :Yb 3+ /Tm 3+ were investigated systematically under 980 nm excitation. The results show that all the UC emission peaks of NaBiF 4 : Yb 3+ /Tm 3+ in the region from 300 to 900 nm decrease with the temperature increase except for the emission peak at 697 nm which is positively correlated with temperature. And the UC emissions of NaBiF 4 : Yb 3+ /Tm 3+ exhibits high temperature sensitivity between 303 and 443 K. Therefore, NaBiF 4 : Yb 3+ /Tm 3+ material with strong NIR UCL could be a potential candidate for sensitive temperature sensor .
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）