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- 实验方案
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Lanthanide-based Nanocomposites for Photothermal Therapy under Near Infrared Laser: Relationship between Light and Heat, Bio-stability and Reaction Temperature
摘要： In this research, typical organic/inorganic photothermal therapy (PTT) agents were designed with combination of up-conversion luminescent (UCL) or NIR II imaging rare earth nanomaterials for photoacoustic (PA)/UCL/NIR II imaging-guided PTT under NIR laser irradiation. The results show that: (1) PTT effect mainly comes from NIR absorption and partly from the UCL light conversion. (2) The visible UCL emission is mainly quenched by the NIR absorption of the coated PTT agent and partly quenched by the visible absorption, indicating the excitation may play a more important role than in the UCL emission process. (3) The bio-stability of the composite might be decided by the synthesized reaction temperature. Among the five inorganic/organic nanocomposite, UCNP@MnO2 is the most suitable candidate for cancer diagnosis and treatment due to its stimuli-response ability to the micro-acid environment of tumor cells and highest bio-stability. The composites generate heat for PTT after entering the tumour cells, and then the visible light emission gradually regains as MnO2 is reduced to colorless Mn2+ ions, thereby illuminating the cancer cells after the therapy.
关键词： Photothermal therapy,Upconversion luminescence imaging,Mito-tracker,Photoacoustic imaging,Inorganic/organic nanocomposite
更新于2025-09-23 15:19:57
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Bi <sub/>2</sub> SiO <sub/>5</sub> @g-SiO <sub/>2</sub> upconverting nanoparticles: a bismuth-driven core–shell self-assembly mechanism
摘要： Core–shell systems have attracted increasing interest among the research community in recent years due to their unique properties and structural features, and the development of new synthetic strategies is still a challenge. In this work, we have investigated lanthanide-doped Bi2SiO5 nanocrystal formation inside mesoporous silica nanoparticles (MSNs). The role of both synthesis temperature and concentration of the bismuth precursor impregnated into the MSNs is discussed, showing an unprecedented strategy for the simultaneous stabilization of a crystalline core and a glassy shell. Temperature dependent synchrotron radiation X-ray powder diffraction (SR-XRPD) and high resolution transmission electron microscopy (HR-TEM) analyses allow one to follow the crystalline core growth. A mechanism for the formation of a Bi2SiO5@g-SiO2 core–shell nanosystem is proposed. In addition, the easy tunability of the color output of the upconverting system is demonstrated by means of suitable doping lanthanide ions with potential applications in several fields.
关键词： upconversion luminescence,mesoporous silica,core–shell nanoparticles,bismuth silicate,Bi2SiO5
更新于2025-09-19 17:15:36
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Laser induced thermochromism and reversible upconversion emission modulation of a novel WO3:Yb3+,Er3+ ceramic: dual-modal fingerprint acquisition application
摘要： The quick and accurate identity recognition can be obtained by the acquisition of fingerprints in the financial, telecommunication, transportation, education and medical fields. However, conventional fingerprint acquisition technologies have many problems such as the high background interference, low detection sensitivity and complicated operation. In this work, the reversible modulation of laser induced thermochromism and upconversion luminescence of a novel WO3:Yb3+,Er3+ ceramic was achieved even after several cycles, exhibiting excellent repeatability. For the first time, we realized the dual-modal fingerprint acquisition by means of the laser induced thermochromism and upconversion luminescence of WO3:Yb3+,Er3+ ceramic. Particularly, this method shows ultrahigh stability, preserving the fingerprint patterns as long as one year. The results demonstrated that our technology is nondestructive, repeatable, highly effective and stable, paving the way for the development of the acquisition and storage of fingerprints.
关键词： Photo-thermal-chromism,Upconversion luminescence,WO3:Yb3+,Er3+ ceramics,Fingerprint acquisition
更新于2025-09-19 17:13:59
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High-performance upconversion luminescent waveguide using a rare-earth doped microtube with beveled ends
摘要： Upconversion luminescence-based waveguides can achieve optical signal transmission and visible light emission with near-infrared light excitation and their quality is highly dependent on the coupling efficiency between the light and waveguide. Here, a new luminescent waveguide formed by a rare-earth doped microtube with beveled ends was designed to increase the optical coupling efficiency for vertical waveguide-excitation. The beveled end enabled the near-infrared light to effectively couple into the waveguide and produce a visible transmission pattern and directional emission, which was not possible using conventional luminescent waveguides without beveled ends. It was found that the beveled end can not only improve the input and the output signal efficiency, but also control the coupling efficiency and transmission pattern. In particular, a coupling efficiency of B68% could be obtained with the optimized beveled waveguide with a rotation angle of 301. The high optical coupling efficiency and multi-channel luminescent waveguide enabled by the microtube with beveled ends allowed for a deeper understanding of vertical waveguide excitation, and it extends the potential applications of luminescent waveguides for bioimaging and optical communication.
关键词： rare-earth doped microtube,beveled ends,upconversion luminescence,waveguide,optical coupling efficiency
更新于2025-09-16 10:30:52
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Upconversion luminescence of CaF2-SrF2-ErF3 single crystals upon 1.5 μm laser excitation
摘要： In present work, the spectral-luminescent properties of CaF2-SrF2-ErF3 (CaF2-SrF2:Er) single crystals were investigated. The upconversion luminescence (UCL) of CaF2-SrF2: Er in the visible and infrared spectral regions upon excitation of the 4I13/2 level Er3+ ions were studied for the first time. The absolute energy yields of the UCL upon laser excitation at 1.5 μm are determined for CaF2-SrF2:Er. The possible application of fluoride crystals for increasing the efficiency of solar cells was discussed.
关键词： upconversion luminescence,single crystals,solar cells,CaF2-SrF2-ErF3
更新于2025-09-16 10:30:52
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Near-infrared Laser Triggered Full-Color Tuning Photon Upconversion and Intense White Emission in Single Gd2O3 Microparticle
摘要： Full-color emission fluorescence materials are of imperious demands in information storage, graphics imaging and anti-counterfeiting fields. However, it is still a formidable challenge to develop a single material with full-color emission and high purity white output under a NIR-light excitation. Herein, we design a novel and convenient strategy to tune the upconversion luminescence color with full color range in lanthanide ions doped Gd2O3 microspheres via a single NIR laser sensitization. Different from the typical ion-dependent tuning of color, the bright and flexible full-color emission tuning from blue to cyan, green, yellow, pink, and red can be controllable implementation in a single microparticle. Particularity, benefiting from the laser sensitive color adjustment, highly intense white color emission can be simultaneously achieved in diverse doped ion concentration particles. In addition, the upconversion emission intensity has been evidently improved if using a NIR laser sensitization, leading to significantly enhanced upconversion red luminescence signal (44-fold) at the power 446 mW. The mechanistic investigations and dynamics analysis reveal that the unprecedented color tunability from these microcrystals is attributed to dynamic control of multi-energy transfer and multi-cross relaxation process. Furthermore, owning to their excellent upconversion luminescence properties, Gd2O3 microparticles could be used to the anticounterfeiting application in different colors. These findings not only open a way to fabricate a single material to fine tuning upconversion emission in a full color gamut, but also give the possibility to construction of the multicolor imaging for anti-counterfeiting applications.
关键词： upconversion luminescence,anti-counterfeiting,full color emission,lanthanide ions doped Gd2O3 microspheres,white color emission,laser sensitization
更新于2025-09-16 10:30:52
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Tunable upconversion luminescence and optical temperature sensing based on non-thermal coupled levels of Lu3NbO7:Yb3+/Ho3+ phosphors
摘要： The color-tunable upconversion (UC) emission and optical temperature sensing based on non-thermal coupled levels (NTCL) were observed from the Yb3t/Ho3t codoped Lu3NbO7 phosphors synthesized by the solid-state method. The phosphors are capable of generating color tunable UC luminescence from green (yellow) to yellow (green) with the increase of the Yb3t concentration. The tunable emission is due to the different energy back transfer processes from Ho3t to Yb3t. The temperature sensing performances are investigated in the temperature range of 293–573 K based on NTCL by using fluorescence intensity ratio technology. The maximum absolute sensitivities are 0.37%K?1, 0.94%K?1, 0.27%K?1 at 298 K, which are based on three pairs NTCL of (5F4/5S2→5I8)/(5F5→5I8), (5F5→5I8)/(5F4/5S2→5I7) and (5F4/5S2→5I8)/(5F4/5S2→5I7) of Ho3t, respectively. The above results suggest that the as-prepared Lu3NbO7:Yb3t/Ho3t phosphors have great potential for the application prospects of upconverter, color tunable device and optical temperature sensor.
关键词： Phosphor,Optical temperature sensing,Lu3NbO7,Upconversion luminescence
更新于2025-09-11 14:15:04
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Augmenting nitrogen removal by periphytic biofilm strengthened via upconversion phosphors (UCPs)
摘要： The application of periphytic biofilm in removing nitrogen from water is limited by the fluctuating nitrogen concentration. Here, we delineate a novel approach to enhance periphytic biofilm performance in nitrogen removal via upconversion luminescence of upconversion phosphors (UCPs). Nitrogen removal rates (14 d) in high nitrogen wastewater (26 mg/L) were significantly improved to 58.6% and 61.4% by UCPs doped with Pr3+ and Li+ and UCPs doped with Pr3+, respectively, and to 95.1% and 95.9% in low nitrogen surface water (2 mg/L), respectively. The stimulation of UCPs optimized the microbial community structure in the periphytic biofilms, and also resulted in good acclimation to use different carbon sources. The enhanced synergic action of cyanobacterial biomass, ratio of Gram +ve to Gram -ve bacteria and carbon source metabolic capacity contributed to the improved nitrogen removal. This novel approach is promising in nitrogen removal from wastewater and surface water with fluctuating initial nitrogen concentration.
关键词： Nitrogen removal,Microbial aggregates,Upconversion luminescence,Microbial community structure,Periphytic biofilm
更新于2025-09-10 09:29:36
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In-situ synthesis and enhanced upconversion luminescence of Y2O3/Y2O2S:Yb3+,Er3+/Tm3+ nanocomposites by reduction of Y2O3:Yb3+,Er3+/Tm3+
摘要： Y2O3/Y2O2S:Ln3+ (Ln = Yb,Er and Yb,Tm) nanocomposites with enhanced upconversion luminescence were successfully prepared by combining hydrothermal with in-situ synthesis method. Under 980 nm excitation, the upconversion luminescence intensity of Y2O3/Y2O2S:Ln3+ increased, and then declined with the rising amount of sulfur powder. Especially, the Y2O3/Y2O2S:Ln3+ nanocomposites can emit brighter upconversion luminescence than those of Y2O3:Ln3+ and Y2O2S:Ln3+. In terms of Y2O3/Y2O2S:Yb3+,Er3+ nanocomposites which were prepared with 0.025g sulfur powder, an unusual 4G11/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions of Er3+ could be observed. Besides, we have constructed a simple upconversion Y2O3/Y2O2S:Yb3+,Er3+@Au nanocomposite, which can be used for rapid sensing of glucose. The limit of detection of glucose level which based on Y2O3/Y2O2S:Yb3+,Er3+@Au was only 0.066 μmol/L. The proposed approach, which we have mentioned above, holds a great practical value for diabetes mellitus detection and clinical diagnosis.
关键词： B. Upconversion luminescence,A. Y2O3/Y2O2S:Yb3+Er3+,D. Glucose detection
更新于2025-09-10 09:29:36
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Effect of Hf <sup>4+</sup> doping on structure and enhancement of upconversion luminescence in Yb:Tm:LiNbO <sub/>3</sub> crystals
摘要： A series of Yb:Tm:LiNbO3 crystals doped with x mol% Hf4+ ions (x = 2, 4, and 6) were grown by the Czochralski method. The dopant occupancy and defect structure of Hf:Yb:Tm:LiNbO3 crystals were investigated by x-ray diffraction and infrared transmission spectra. The influence of Hf4+ ions concentration on UV–VIS–NIR absorption spectra of Hf:Yb:Tm:LiNbO3 crystals was discussed. The upconversion luminescence of Hf:Yb:Tm:LiNbO3 crystals was obtained under 980 nm excitation. Strong emissions were observed at 475 nm in the blue wavelength range and 651 nm in the red wavelength range. Remarkably, enhancement of the red and blue upconversion luminescence was achieved by tridoping Hf4+ ions.
关键词： crystal structure,Hf:Yb:Tm:LiNbO3 crystals,upconversion luminescence
更新于2025-09-09 09:28:46