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Near-Infrared-Laser-Driven Robust Glass-Ceramic-Based Upconverted Solid-State-Lighting
摘要： Laser lighting, generally consisting of blue laser and downconversion phosphors, is considered to be the next promising illumination to replace traditional LED lighting. However, the irradiation of high-power blue laser will inevitably cause significant thermal attack, which puts forward high demand on phosphor converters as well as device architecture. In this work, a proof-of-concept prototype of near-infrared laser-driven upconversion solid-state-lighting is proposed. Robust lanthanide doped α/β-NaYF4 embedded glass ceramics are developed as upconverted color converters and routine 980 nm laser is used as pumping source for its relatively low thermal effect and a perfect resonance with Yb3+ sensitizers. Stable and bright upconversion white light is indeed produced by coupling Yb/Tm/Er doped α-NaYF4 glass ceramic with 980 nm laser but the luminous efficiency and energy efficiency are only 0.3 lm/W and 0.12%, respectively, owing to low Er doping concentration. As an alternative, a stacking structure of Yb/Tm doped glass ceramics and Yb/Er doped one is designed as color converter to improve luminous efficiency up to 1.0 lm/W and energy efficiency of 0.5% under a laser power density of 275 W/cm2. It is believed that this research will provide a new idea for laser lighting and open the application field of glass ceramics.
关键词： upconversion,lanthanide ions,optical materials,glass ceramics,laser lighting
更新于2025-11-20 15:33:11
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Remarkable laser-driven upconverting photothermal effect of Cs3LnF6@glass nanocomposites for anti-counterfeiting
摘要： Currently, advanced security strategies have aroused widely interest in anti-counterfeiting field to ensure the authentic items difficult to be replicated. Herein, cubic Cs3LnF6 (Ln = Y, Yb, Lu, Sc) nanocrystals embedded glasses are successfully prepared via an in-situ glass crystallization strategy. Emitting centers, such as Eu3+, Er3+, Ho3+ and Tm3+, can be incorporated into the precipitated Cs3YF6, Cs3YbF6 and Cs3LuF6 crystal lattices but remain in glass matrix rather than in Cs3ScF6 crystals for large ionic radius mismatch between lanthanide activators and Sc3+ host ions. It is demonstrated that upconverting quantum yields of all the Yb/Er: Cs3LnF6@glass samples are higher than those of well-known cubic/hexagonal Yb/Er: α/β-NaYF4@glass samples. Specifically, Yb/Er: Cs3LuF6@glass exhibits a maximal quantum yield of ~0.30%, which is superior to Yb/Er: β-NaYF4 @glass (~0.19%). Impressively, Er: Cs3YbF6@glass shows a remarkable 980 nm laser-induced photothermal effect, leading to significant alteration of upconversion emissive color from red to green with increase of incident laser power. As a prototype of the concept for practical application, a series of luminescent patterns using Er: Cs3YbF6@glass upconverting inks are constructed by a screen-printing technique and show distinct laser-power-sensitive emissive colors, being feasible for high-level anti-counterfeiting. The present work exploits a new anti-counterfeiting strategy by developing highly efficient laser-induced upconverting photothermal materials.
关键词： Anticounterfeit,Nanocomposites,Upconversion,Lanthanide ions,Photothermal effect,Luminescent glasses
更新于2025-10-22 19:38:57
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Optical Pressure Sensor Based on the Emission and Excitation Band Width (FWHM) and Luminescence Shift of Ce3+ Doped Fluorapatite – High-Pressure Sensing
摘要： A novel, contactless optical sensor of pressure based on the luminescence red-shift and band width (full width at half maximum - FWHM) of the Ce3+-doped fluorapatite - Y6Ba4(SiO4)6F2 powder, has been successfully synthesized via a facile solid-state method. The obtained material exhibits a bright blue emission under UV light excitation. It was characterized using powder X-ray diffraction, scanning electron microscopy and luminescence spectroscopy, including high-pressure measurements of excitation and emission spectra, up to above ≈30 GPa. Compression of the material resulted in a significant red-shift of the allowed 4f→5d and 5d→4f transitions of Ce3+ in the excitation and emission spectra, respectively. The pressure-induced monotonic shift of the emission band, as well as changes in the excitation/emission band widths, have been correlated with pressure for sensing purposes. The material exhibits a high pressure sensitivity (dλ/dP ≈0.63 nm/GPa), and outstanding signal intensity at high-pressure conditions (≈90% of the initial intensity at around 20 GPa) with minimal pressure-induced quenching of luminescence.
关键词： Ce3+ doping,Contactless pressure gauge,Y6Ba4(SiO4)6F2 apatite phosphors,Lanthanide ions (Ln3+),Compression in DAC,Luminescent functional materials
更新于2025-09-23 15:23:52
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[IEEE 2017 5th International Conference on Instrumentation, Communications, Information Technology, and Biomedical Engineering (ICICI-BME) - Bandung, Indonesia (2017.11.6-2017.11.7)] 2017 5th International Conference on Instrumentation, Communications, Information Technology, and Biomedical Engineering (ICICI-BME) - Enhancement of Luminescence Light Yield of Ln <sup>3+</sup> Doped Glass By Oxyfluoride Glass Matrix
摘要： Glass is a good material which received attention for doping lanthanide ions. Glass doped Ln3+ ions can show luminescence, but not too strong light yield. It is well known that the host glass plays an important role in the enhancement. This paper has been described effect of Ln3+ ions (Sm3+, Eu3+ and Dy3+) doped oxyfluoride glass by comparing between oxide and oxyfluoride glasses. For the Sm3+ doped gadolinium calcium phosphate oxyfluoride glass, the highest emission peak was 598 nm under 401 nm excitation. While the emission light yield of oxyfluoride glass was higher than oxide glass due to the reduction of phonon and non-radiative losses. In case of Eu3+ doped oxyfluoride glass, the 612 nm emission under 394 nm excitation was observed. The light yield of oxyfluoride glass also was better than oxide glass. The Dy3+-doped phosphate oxide and oxyfluoride glasses were investigated. The luminescence light yield of oxyfluoride glass was more than oxide glass as well, owing to lower OH group of oxyfluoride glass, which can be confirmed by FTIR measurement. As described earlier, it concludes that the oxyfluoride glass is better than glass matrix when compared with oxide glass to enhance luminescence light yield for Ln3+ ions in glass matrix.
关键词： phonon energy,oxyfluoride glass,oxide glass,lanthanide ions
更新于2025-09-23 15:22:29
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Europium and terbium lanthanide ions co-doping in TiO2 photoanode to synchronously improve light-harvesting and open-circuit voltage for high-efficiency dye-sensitized solar cells
摘要： In this study, we explore the effects on the incorporation of europium (Eu3+) and terbium (Tb3+) rare-earth ions into titanium dioxide (TiO2) photoanodes in dye-sensitized solar cells (DSSCs). X-ray photoelectron spectroscopy (XPS) studies affirm that the Eu3+ ions are arranged at the cationic locales of Ti4+ in the matrix whereas the site inhabitance was remunerated by Tb3+ ions, supporting that the anatase phase stays unaltered without generating any new deformities. Additionally, the Eu3+ ions decidedly changed the conduction band minimum of TiO2, actually, Tb3+ ions contrarily conversion because of various vacant trap states in the band gap. Besides, the photoinduced electron transfer estimations show an efficient interfacial charge transfer for co-doped TiO2 (kET = 3.1 ns) contrasted with the bare TiO2 (2.6 ns). DSSCs based on Eu3+/Tb3+ co-doped TiO2 display higher efficiency (9.11%) than those for the bare TiO2 (7.20%) and the exclusively Eu3+ (8.01%) or Tb3+ (7.10%) doped samples, which is ascribed to the joined impact of a faster electron transportation and longer electron lifetime in the co-doped TiO2 film. This work may open another approach to further improve the performance of DSSCs by Eu3+/Tb3+ co-doping technique, advancing the development of DSSCs toward commercial applications.
关键词： Co-doping process,Europium (Eu3+)/terbium (Tb3+) lanthanide ions,Stability,Photoanodes,DSSCs,Titanium dioxide (TiO2) nanopowders
更新于2025-09-23 15:21:01
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Engineering efficient upconverting nanothermometers using Eu <sup>3+</sup> ions
摘要： Upconversion nanothermometry combines the possibility of optically sensing temperatures in very small areas, such as microfluidic channels or on microelectronic chips, with a simple detection setup in the visible spectral range and reduced heat transfer after near-infrared (NIR) excitation. We propose a ratiometric strategy based on Eu3+ ion luminescence activated through upconversion processes. Yb3+ ions act as a sensitizer in the NIR region (980 nm), and energy is transferred to Tm3+ ions that in turn excite Eu3+ ions whose luminescence is shown to be thermally sensitive. Tridoped SrF2:Yb3+,Tm3+,Eu3+ nanoparticles (average size of 17 nm) show a relative thermal sensitivity of 1.1% K-1 at 25.0 °C, in the range of the best ones reported to date for Ln3+-based nanothermometers based on upconversion emission. The present nanoparticle design allows us to exploit upconversion of lanthanide ions that otherwise cannot be directly excited upon NIR excitation and that may provide operational wavelengths with a highly stable read out to fill the spectral gaps currently existing in upconversion-based nanothermometry.
关键词： nanothermometry,nanoparticles,upconversion,ratiometric strategy,lanthanide ions,Eu3+
更新于2025-09-19 17:15:36
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Electronic structure and optical properties of Ln(III) nitrate adducts with 1,10-phenanthroline
摘要： Adducts of tris-nitrates of rare-earth elements Ce(III), Nd(III), Eu(III), and Er(III) with two molecules of 1,10-phenanthroline with formula Ln(NO3)3(Phen)2 are studied by X-ray photoelectron spectroscopy (XPS) and quantum chemistry (DFT/TDDFT). The geometric structure for DFT modeling is build using X-ray diffraction data. To analyze the composition and differences of the electronic structure in the series under study, XPS spectra were obtained for which interpretation was performed using calculated data. It has been shown that the molecule of Phen, when attached to the complexes of nitrates, is polarized, leads to an increase in absorption in the visible region and reduces the energy gap between HOMO and LUMO. Experimental absorption spectra were obtained, described and interpreted using TDDFT simulation. The transitions in adducts from π to π * MO in Phen ligands determine the main absorption band. The reasons for the absence of luminescence in adducts with ions Ce(III), Nd(III), and Er(III) are revealed by the example of the correlation diagram of singlet and triplet levels. A possible origin of coloring of adducts is determined using TDDFT.
关键词： Optical properties,Nitrates,DFT,Lanthanide ions,Photoelectron spectroscopy
更新于2025-09-19 17:15:36
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A series of two-dimensional lanthanide coordination polymers: synthesis, structures, magnetism and selective luminescence detection for heavy metal ions and toxic solvents
摘要： A series of two-dimensional lanthanide coordination polymers: synthesis, structures, magnetism and selective luminescence detection for heavy metal ions and toxic solvents
关键词： lanthanide ions,coordination polymers,luminescence properties,crystal structure,magnetic properties
更新于2025-09-19 17:15:36
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Eu3+ as a luminescence probe in DNA studies: Structural and conformational implications
摘要： Lanthanide ions are widely used as luminescent probes for structural studies of various biomolecules, including DNA. Latest developments of circularly polarized luminescence (CPL) methodology further boosted interest to luminescence techniques. However, an effect of the lanthanide probes themselves on the DNA structure and conformation was investigated only partially and not for all lanthanides. In the present work, we performed a detailed spectroscopic study of Eu3+ complexes with native double-stranded DNA and compared them to the relevant complexes with single-stranded DNA. We employed infrared (IR), vibrational circular dichroism (VCD) and electronic circular dichroism (ECD) spectroscopic methods to investigate Eu3+ effect on DNA structure and conformational transitions. It was shown that Eu3+ ions can induce significant alteration of the native DNA structure at the concentrations often used in luminescence studies. While no DNA denaturation was observed at these metal ion concentrations, significant unstacking of the base pairs and disordering of the sugar-phosphate backbone, partial appearance of the A-form backbone geometry, and DNA transition into condensed ψ–type form took place. Eu3+ binding to single-stranded DNA was more pronounced than the binding to double-stranded DNA. We detected the main Eu3+ binding sites and determined the metal ion concentration range in which DNA geometry remains largely unaltered. The results obtained in the current study could be used for tuning the luminescence and CPL structural studies of DNA utilizing Eu3+ ions as probes.
关键词： infrared (IR),DNA condensation,lanthanide ions,DNA structure,luminescence probe,vibrational circular dichroism (VCD)
更新于2025-09-19 17:15:36
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Full-color persistent luminescence tuning: A marriage of perovskite quantum dots and lanthanide ions
摘要： In modern society, luminescent materials capable of emitting various colored lights are critically important for lighting and display systems. As a typical kind of luminescent materials, the persistent luminescence phosphors have been widely investigated as night-light vision materials due to their many significant applications such as emergency route signage and security signals, bio-labels, photocatalysts, anti-counterfeiting, optical sensors, and optical data storage. However, realizing multicolored persistent luminescence phosphors has been a long-standing challenge, thus posing a serious problem in their practical applications. In a recent publication in Angewandte Chemie International Edition, Prof. Xueyuan Chen and co-workers demonstrated a simple but effective approach to fine-tuning the persistent luminescence colors, based upon the composites of lanthanide ions doped CaAl2O4:Eu2+,Nd3+ (CAO) blue persistent phosphors with all-inorganic CsPbX3 (X = Cl, Br, and I) perovskite quantum dots (PeQDs). With the help of the radiative energy transfer from CAO blue persistent phosphors to CsPbX3 PeQDs, the persistent luminescence colors can be precisely controlled through tailoring of the PeQDs bandgap. The approach allowed access to full-spectrum persistent luminescence with wavelengths covering the entire visible spectral range by single-wavelength excitation, thus offering new opportunities for persistent luminescence materials in many important emerging applications.
关键词： persistent luminescence,lanthanide ions,full-color tuning,perovskite quantum dots
更新于2025-09-16 10:30:52