Luminescence Thermal Stability Research Articles

Boosting the red emission and luminescent thermostability of GdPO4:Eu3+ phosphors by coating with graphitic carbon nitride

Due to the fact that the luminescence of Eu3+ belongs to orbital forbidden f→f transition, the luminous intensity of Eu3+-activated phosphors is relatively weak. In this work, in order to increase the luminous intensity of GdPO4:Eu3+, a series of GdPO4:Eu3+@g-C3N4 phosphors was obtained via conventional solid-state reaction, with GdPO4:0.05Eu3+@0.005 g-C3N4 identified as the optimal sample. The characterization results indicate that: (a) The coating of g-C3N4 not only enhances the luminescence, but also unexpectedly induces a relatively weak negative thermal quenching (NTQ) effect, thereby obviously improving its luminescence thermal stability. The mechanisms behind the enhanced luminescence and luminescence thermal stability are explored, and attributed energy transfer from g-C3N4 to Eu3+ and phonon electron interaction, respectively. (b) The WLED prepared with GdPO4:0.05Eu3+@0.005 g-C3N4 and yellow fluorescent phosphor (YAG:Ce3+) forms warm-white light under excitation of ultraviolet light. The findings reveal that GdPO4:0.05Eu3+@0.005 g-C3N4 is a potential candidate for using in the field of warm WLEDs excited by ultraviolet light.

Spectral studies of thermally stable Dy3+/Sm3+ co-doped Li2Ba5W3O15 phosphors for warm white LEDs

In the current study, a series of Li2Ba5W3O15: RE3+ (RE = Dy, Sm) [LBW:Dy3+/Sm3+] phosphors were prepared using a high-temperature solid-state method. X-ray diffraction, Scanning electron microscopy with energy-dispersive x-ray analysis scans showed that the crystal form was consistent with the standard LBW and comprised small irregularly shaped particles. Diffuse reflectance spectral (DRS) data was utilized to calculate the band gaps. Fluorescence study shows that LBW material doped with Dy3+ and Sm3+ yield distinct colors at 496 nm (blue) for Dy3+ and 582 nm (green-yellow), 612 nm (yellow), and 669 nm (red) for Sm3+ when excited by near-ultraviolet (336 nm) light. The observation of energy transfer between Dy3+ and Sm3+ ions play a role in modifying the luminescence of LBW:Dy3+/Sm3+ co-doped phosphors. With a constant excitation wavelength (λ Ex), different levels of activator doping lead to a change in the emission colors from their neutral white light to a deep orange-red region for LBW:Dy3+/Sm3+ phosphors. The decay curves demonstrate a decrease in lifetime with an increase in the concentration of activator ions (Sm3+). For D3S5 phosphor, the temperature-dependent photoluminescence characteristics were analyzed under λ Ex = 336 nm excitation. The results indicate excellent luminescence thermal stability with an activation energy of 0.16 eV at λ Ex = 336 nm. With its low color-correlated temperature and good thermal stability, the prepared phosphor sample shows potential as a solid-state emitting phosphor that can be used with UV chip stimulation for warm white LED applications.

Optimization of near-infrared luminescence performance in Cr3+-doped double perovskite Sr2ScTaO6 phosphor by Nb5+ ion substitution

Here, Nb5+ were partially substituted for Ta5+ in the double perovskite Sr2ScTaO6: Cr3+ phosphor to improve its luminescence performance and finally obtained the optimized phosphor Sr2ScTa0.6Nb0.4O6: Cr3+. The structure, substitution mechanism, luminescence optimization mechanism, crystal field, and thermal stability of the phosphor were all thoroughly explored. The results indicate that introducing Nb5+ into Sr2ScTaO6: Cr3+ can cause lattice distortion in the host, and the distorted crystal lattice can break the forbidden transition of Cr3+, thereby enhancing its absorption of excitation light. At the same time, the full width at half maximum of the phosphor emission increased from 176.4 nm to 179.7 nm. And the internal quantum efficiency, absorption efficiency, and external quantum efficiency of the optimized Sr2ScTa0.6Nb0.4O6: Cr3+ phosphor can reach 86.3%, 49% and 42.3%, respectively. The photoelectric conversion efficiency of the optimized pc-LED increased from 5.63% to 7.80%@100 mA, indicating the introduction of Nb5+ in Sr2ScTaO6: Cr3+ improved the luminescence performance of phosphor. The above results provide directions for the development of more efficient and promising double-perovskite NIR phosphors.

Unraveling the Defect‐Induced Spectral Tuning in a Ce‐Doped Garnet Solid‐Solution Phosphor

Unraveling the Defect‐Induced Spectral Tuning in a Ce‐Doped Garnet Solid‐Solution Phosphor

Simultaneous NIR Emission and Thermal Stability Enhancement in Garnet‐Type NIR Phosphors through the Synergistic Effect of Lattice Distortion and Enhanced Rigidity

AbstractEven though there have been significant advancements in the development of Cr3+‐activated near‐infrared (NIR) phosphors, the challenge still remains to develop highly efficient and thermally stable NIR phosphors. Here, the Ca4‐xZnxHfGe3O12:0.03Cr3+ solid solution phosphors with 834–806 nm NIR emission are constructed by substituting Zn2+ for Ca2+, thereby facilitating the formation of [ZnO6] luminescence site. The coexistence of [HfO6] and [Zn/CaO6] luminescence centers is confirmed through DFT calculation, time‐resolved photoluminescence (TRPL) spectroscopy, and low‐temperature‐photoluminescence (77 K) spectroscopy. The formation of [ZnO6] effectively resolves the issue of lattice mismatch between Cr3+ and Ca2+. Furthermore, the simultaneous enhancement of luminescence intensity and thermal stability is realized through a synergistic combination of lattice distortion and rigidity enhancement. By optimizing the substitution concentration of Cr3+, the internal quantum efficiency (IQE) of 92% and an external quantum efficiency (EQE) of 29% are finally achieved. Meanwhile, the thermal stability is also enhanced from 59%@400 K (x = 0) to 81%@400 K (x = 0.8). The developed NIR phosphor‐converted light‐emitting diodes (pc‐LEDs) exhibit promising prospects in the fields of security, biomedicine, non‐destructive testing and rapid identification.

Two-Site Occupation for Constructing Double Perovskite BaLaMgNbO6:Cr3+ Ultrabroadband NIR Phosphors.

Given the escalating significance of near-infrared (NIR) spectroscopy across industries, agriculture, and various domains, there is an imminent need to address the development of a novel generation of intelligent NIR light sources. Here, a series of Cr3+-doped BaLaMgNbO6 (BLMN) ultrabroadband NIR phosphor with a coverage range of 650-1300 nm were developed. The emission peak locates at 830 nm with a full width at half maximum of 210 nm. This ultrabroadband emission originates from the 4T2→4A2 transition of Cr3+ and the simultaneous occupation of [MgO6] and [NbO6] octahedral sites confirmed by low photoluminescence spectra (77-250 K), time-resolved photoluminescence spectra, and electron paramagnetic resonance spectra. The fluxing strategy improves the luminescence intensity and thermal stability of BLMN:0.02Cr3+ phosphors. The internal quantum efficiency (IQE) is 51%, external quantum efficiency (EQE) can reach 33%, and thermal stability can be maintained at 60%@100 °C. Finally, we successfully demonstrated the application of BLMN:Cr3+ ultrabroadband in the qualitative analysis of organic matter and food freshness detection.

UVC Stokes and Anti-Stokes Emission of Ca9Y(PO4)7 Polycrystals Doped with Pr3+ Ions.

The recent COVID-19 pandemic has made everyone aware of the threat of viruses and the growing number of antibiotic-resistant bacteria. It has become necessary to find new methods to combat these hazards. One tool that could be used is UVC radiation, i.e., 100-280 nm. Currently, the available sources of this light are mercury vapor lamps. However, the modern world requires more compact, mercury-free, and less energy-consuming light sources. This work presents the results of our research on a new material in which efficient UVC radiation was obtained. Here, we present the results of research on Ca9Y(PO4)7 polycrystals doped with Pr3+ ions prepared using the solid-state method. The absorption, excitation, emission, and emission decay profiles of praseodymium(III) ions were measured and analyzed. The upconversion emission in the UVC region excited by blue light was observed. Parameters such as energy bandgap, refractive index, and thermal stability of luminescence were determined. The studied phosphate-based phosphor possesses promising characteristics that show its potential in luminescent applications in future use in medicine or for surface disinfection.

Highly thermally stable SrLaMgTaO6: Cr3+ double-perovskite phosphors for night-vision applications

In this study, a novel thermally stability broad-band near-infrared (NIR) phosphor SrLaMgTaO6 (SLMT): Cr3+ was research, along with investigations into its structure, morphology, PL spectra and crystal field strengths. Additionally, the mechanism of concentration quenching in these samples was investigated, which primarily attributed to electric multipolar interactions notably. Surprisingly, the NIR emission intensity at 423 K remains 80.4 % of its room temperature intensity, which shows its outstanding thermal stability. To comprehend the mechanism behind the exceptional thermal stability of luminescence, a comprehensive analysis in this material was conducted, focusing on factors such as the crystal field strength of the host material and the electron-phonon coupling (EPC) effect. Subsequently, an optimized phosphor coating was applied to a 470 nm LED chip to get a NIR pc-LED device, which was evaluated for its performance. The research demonstrate that SLMT: Cr3+ phosphor is a promising NIR pc-LED.

Luminescence properties of complex fluoride Na3CaMg3AlF14 phosphors doped with cerium and europium ions

Ceramic samples of two multi-cation fluoride compositions, namely Na3CaMg3AlF14 doped with Ce3+ or Eu2+ and KCaAl2F9 doped with Eu2+, have been synthesized using a conventional solid-state reaction method. The XRD analysis shows that the new polymorphic modification of Na3CaMg3AlF14 with the cubic A2B2X7 pyrochlore crystal structure (space group Fd3‾m, lattice parameter 10.172 Å) has been obtained. This conclusion is confirmed with the simulation of the XRD pattern for the cubic pyrochlore structure by introducing random occupation of Na+ and Ca2+ ions at the A-type sites as well as Mg2+ and Al3+ ions at the B-type sites in the structure of rhombohedral Na3CaMg3AlF14. It has been shown that doping of the Na3CaMg3AlF14 pyrochlore matrix with Ce3+ ions creates several Ce3+ optical centers with different spectral and decay properties of 5d-4f luminescence. In contrast to that, doping with Eu2+ ions creates a single optical center by the substitution for the Na/Ca A-type site in the cubic Na3CaMg3AlF14 pyrochlore structure. In Eu2+-doped Na3CaMg3AlF14, the Eu2+ emission band caused by the interconfigurational 4f65d – 4f7 transition has a rather narrow width (FWHM = 29 nm) which is considerably less than that observed in Eu2+-doped KCaAl2F9 (FWHM = 44 nm) in which the emission band is broadened due to the existence of two types of sites for doping Eu2+ ions. The Eu2+ ions doped into Na3CaMg3AlF14 and KCaAl2F9 hosts emit not only broad-band 4f65d – 4f7 luminescence but also a narrow-line 4f7 – 4f7 (6P7/2 - 8S7/2) emission which is not observed under excitation to the lowest-energy 4f65d state. It has been shown that both Na3CaMg3AlF14:Eu2+ and KCaAl2F9:Eu2+ demonstrate a rather good thermal stability of luminescence with thermal quenching temperature T1/2 equal to 504 and 573 K, respectively.

Double-perovskite compound Na2ZrTeO6: Synthesis, structure and self-activated near-infrared luminescence

Perovskite compounds are always the focus in the material research field. Herein, the polycrystalline samples and single crystals of Na2ZrTeO6, a B-site ordered double-perovskite compound, were prepared successfully. Single crystal X-ray diffraction demonstrated that Na2ZrTeO6 crystallizes in the cubic space group Fm-3m (No. 225) with unit parameters of a = b = c = 7.80360(10) Å. The crystal structure of Na2ZrTeO6, formed by ZrO6 and TeO6 octahedra through sharing the corner oxygen atoms, belongs to the typical rock-salt-type perovskite structure. The density functional theory calculations show that Na2ZrTeO6 has a direct band gap with band gap of 3.21 eV, which is lower than the experimental value of 3.85 eV. Interestingly, the powder samples of Na2ZrTeO6 exhibit a self-activated near-infrared emission centered at 780 nm under ultraviolet light excitation. And a strong luminescence thermal stability was also observed. Compared to room temperature, the luminescence intensity can maintain 64 % at 200 °C.

Unraveling Broadband Near-Infrared Luminescence in Cr3+-Doped Ca3Y2Ge3O12 Garnets: Insights from First-Principles Analysis.

In this study, we conducted an extensive investigation into broadband near-infrared luminescence of Cr3+-doped Ca3Y2Ge3O12 garnet, employing first-principles calculations within the density functional theory framework. Our initial focus involved determining the site occupancy of Cr3+ activator ions, which revealed a pronounced preference for the Y3+ sites over the Ca2+ and Ge4+ sites, as evidenced by the formation energy calculations. Subsequently, the geometric structures of the excited states 2E and 4T2, along with their optical transition energies relative to the ground state 4A2 in Ca3Y2Ge3O12:Cr3+, were successfully modeled using the ΔSCF method. Calculation convergence challenges were effectively addressed through the proposed fractional particle occupancy schemes. The constructed host-referred binding energy diagram provided a clear description of the luminescence kinetics process in the garnet, which explained the high quantum efficiency of emission. Furthermore, the accurate prediction of thermal excitation energy yielded insights into the thermal stability of the compound, as illustrated in the calculated configuration coordinate diagram. More importantly, all calculated data were consistently aligned with the experimental results. This research not only advances our understanding of the intricate interplay between geometric and electronic structures, optical properties, and thermal behavior in Cr3+-doped garnets but also lays the groundwork for future breakthroughs in the high-throughput design and optimization of luminescent performance and thermal stability in Cr3+-doped phosphors.

Efficient broadband NIR garnet phosphor Ca2LuScGa2Si2O12:Cr3+,Yb3+ for NIR pc-LED applications

Near-infrared phosphor-converted light emitting diodes (NIR pc-LEDs) have broad application prospects in the fields of solar cells, spectroscopic analysis, fluorescent labeling and biomedical testing. The current research faces challenges in enhancing the thermal stability and efficiency of near-infrared (NIR) emitting phosphors. Herein, a broadband NIR phosphor Ca2LuScGa2Si2O12:Cr3+ (CLSGS:Cr3+) was successfully synthesized. CLSGS:Cr3+ phosphor displays a broadband emission in the range (650–900 nm) with a full width at half maximum (FWHM) of 150 nm, a good luminescent thermal stability (I373K/I298K = 73%), and a high internal quantum efficiency (IQE = 70.3%). Moreover, the introducing Yb3+ into CLSGS:Cr3+ significantly improves thermal stability (I373K/I298K = 93%) and enhances internal quantum efficiency (IQE = 90.5%). By combining CLSGS:Cr3+,Yb3+ with a 460 nm commercial LED chip, the fabricated NIR pc-LED devices demonstrates potential applicability in night vision and bio-imaging.

High‐Efficiency Short‐Wave Infrared Emitter Enabled by Cr3+–Yb3+ Co‐Doped Phosphor

AbstractThe utilization of phosphor‐converted light‐emitting diodes (pc‐LEDs) as compact short‐wave infrared (SWIR) emitters has emerged as a promising strategy for miniature SWIR spectrometers in portable devices, enabling diverse applications such as nondestructive identification, bioimaging, night‐vision surveillance, and optical communication. However, discovering phosphors capable of efficiently absorbing blue light and emitting pure SWIR light (>900 nm) remains a significant challenge. Here, highly efficient and thermally stable SWIR luminescence of Yb3+ upon blue LED excitation by employing Cr3+–Yb3+ energy transfer in Y3Ga5O12 garnet is reported. The prepared Y3Ga5O12:Cr3+,Yb3+ phosphor exhibits intense SWIR emission spanning from 900 to 1150 nm at 438 nm excitation, coupled with ultra‐high internal/external quantum efficiency of 80.8%/40.2% and excellent luminescence thermal stability (108%@150 °C). A SWIR pc‐LED prototype fabricated by incorporating the optimized phosphor with a commercial 450 nm blue LED chip, shows exceptional SWIR luminescence performance, delivering a SWIR output power of 92.7 mW at a driving current of 350 mA and a photoelectric efficiency of 21.5% at 10 mA. This work opens up a new avenue for designing SWIR phosphors that exhibit efficient and thermally stable photoluminescence with blue LED excitation, demonstrating significant potential for next‐generation high‐power compact SWIR light sources.

Achieving broadband near-infrared luminescence in Cr3+-Activated Y2Mg2Al2Si2O12 phosphors via multi-site occupancy

Cr3+-activated near-infrared (NIR) phosphors are key for NIR phosphor-converted light emitting diodes (NIR pc-LED). While, the site occupancy of Cr3+ is one of the debates that have plagued researchers. Herein, Y2Mg2Al2Si2O12 (YMAS) with multiple cationic sites is chosen as host of Cr3+ to synthesize YMAS: xCr3+ phosphors. In YMAS, Cr3+ ions occupy simultaneously Al/SiO4 tetrahedral, Mg/AlO6 octahedral, and Y/MgO8 dodecahedral sites which form three luminescent centers named as Cr1, Cr2, and Cr3, respectively. Cr1 and Cr2 relate to an intermediate crystal field, with transitions of 2E→4A2 and 4T2→4A2 occurring simultaneously. As Cr3+ concentration increases, the 4T2→4A2 transition becomes more pronounced in Cr1 and Cr2, resulting in a red-shift and broadband emission. Cr3 consistently behaves a weak crystal field and exhibits the broad and long-wavelength emission. Wide-range NIR emission centering at 745 ​nm is realized in YMAS: 0.03Cr3+ phosphor. This phosphor has high internal quantum efficiency (IQE ​= ​86%) and satisfying luminescence thermal stability (I423 K ​= ​70.2%). Using this phosphor, NIR pc-LEDs with 56.6 ​mW@320 ​mA optical output power is packaged and applied. Present study not only demonstrates the Cr3+ multi-site occupancy in a certain oxide but also provides a reliable approach via choosing a host with diverse cationic sites and local environments for Cr3+ to achieve broadband NIR phosphors.

Efficient broad-band NIR-II emitting phosphor Mg4Ta2O9: Ni2+ with satisfactory thermal stability of luminescence

The applications of near-infrared (NIR) spectroscopy in the fields of medicine and food safety require efficient and compact NIR light sources, for example, NIR phosphor converted light-emitting diodes (pc-LEDs). In recent years, Ni2+ has become one of the main activators for its broadband NIR-II (1000–1700 nm) emission under ultraviolet or visible light excitation. However, two important effects (Concentration quenching which decreases the emission intensity and temperature quenching which decreases the adaptability of phosphor in high-power applications) seriously hinder the development of Ni2+ doped NIR-II emitting phosphors. It is an urgent and important task to restrain both concentration and thermal quenching of the Ni2+ luminescence to develop an efficient NIR-II emitting phosphor. Here, novel NIR-II emitting Mg4Ta2O9: Ni2+ phosphors with perovskite-like structure were synthesized and investigated. In Mg4Ta2O9, the quenching concentration of Ni2+ is as high as 0.045. This is a relatively high value for Ni2+ activated NIR-II emitting phosphors. Mg4Ta2O9: 0.045Ni2+ presents broadband emission (1100–1700 nm, the full width at half maximum (FWHM) = 218 nm) with internal and external quantum efficiency of 64.2% (IQE) and 7.2% (EQE), respectively. The phosphor exhibits excellent luminous thermal stability (at 423 K, it keeps 84.85% of initial intensity at room temperature). High structure stiffness of Mg4Ta2O9 is responsible for the high quenching concentration and desirable luminous thermal stability. This work developed an efficient NIR-II emitting phosphor which exhibits desirable thermal stability of luminescence. Theoretically, this work points out a direction for future development of efficient NIR-II emitting phosphors, selecting an inorganic compound with high structural rigidity as the host for Ni2+ doping.

Site Preference Induced Dual‐Wavelength Mn2+ Upconversion in K2NaScF6:Yb3+, Mn2+ and Its Application in Temperature Sensing

AbstractThe realization of dual‐wavelength Mn2+ upconversion (UC) luminescence that exhibits different thermal responsive behaviors is promising for non‐invasive optical temperature sensing applications. However, it remains challenging to achieve such luminescence of Mn2+ ions. Herein, due to the site preference characteristics of Mn2+, color tunable and dual‐wavelength Mn2+ UC luminescence is achieved in K2NaScF6:Yb3+, Mn2+ by simply adjusting the Mn2+ doping concentration. Structural and spectral analysis as well as theoretical calculations reveal that the green and red UC emissions originate from two kinds of face‐sharing Yb3+‐Mn2+ dimers, which exhibit different luminescence properties, including different emission wavelength, excited state lifetime, full width at half maximum (FWHM), and luminescence thermal stability. This unique dual‐wavelength UC luminescence of Mn2+ provides a new type of fluorescence intensity ratio thermometer with absolute and relative sensitivities of up to 0.018 K−1 and 0.525% K−1, respectively. This work not only demonstrates the potential application of K2NaScF6:Yb3+, Mn2+ material in the field of optical thermometry but also provides new perspectives for designing multi‐band Mn2+ UC luminescence.

Sol-gel combustion synthesis and near-infrared luminescence of Ni2+-doped MgAl2O4 spinel phosphor

Near-infrared phosphor converted light-emitting diode (NIR pc-LED) has many advantages over traditional NIR light sources, and has broad application prospects in night vision surveillance, non-destructive testing, bioimaging, and other fields. Phosphors are typically synthesized by the high-temperature solid-phase method as chunks or large granules, which need to be ground to small particles for practical application. This process introduces surface defects and reduces the luminous efficiency of phosphors. In this work, near-infrared phosphors composed of spinel MgAl2O4:Ni2+ with particle size less than 100 nm was synthesized in high-purity by sol-gel combustion method using nitrate salts with citric acid were used as raw materials. Under 365 nm excitation, MgAl2O4:Ni2+ phosphors emit broadband near-infrared luminescence of 1000–1600 nm with a width at half maximum of 237 nm. The optimal Ni2+ doping concentration was determined to be 1.5 mol% and the optimal sintering temperature was 1200 °C. The thermal activation energy of this phosphor was found to be 0.409 eV and the phosphor had good luminescence thermal stability. An NIR pc-LED device was assembled from the phosphor and commercially available near-ultraviolet LED, which showed a current-dependent increased of NIR luminescence up to 160 mA and an efficiency drop appeared with further increase of the current, suggesting a thermal dependent quenching may have occurred. On the other hand, the output of NIR luminescence increased nearly linearly with the increased of current when a 360 nm laser diode was used as the excitation light source, indicating the NIR phosphor has a very high fluorescence saturation threshold. Our study provides the utility for the sol-gel method in the preparation and the potential application of the nanoscale NIR-II phosphor materials.

Anti-thermal Quenching in Blue Phosphor Ba3YAl2O7.5: Tm3+

Blue-emitting phosphors are essential components of the color plasma display panel (PDP), white light-emitting diodes (W-LEDs), and liquid crystal display (LCD) backlights. However, the thermal quenching effect of the phosphor is a serious problem in practice. In this work, a new kind of blue phosphor Ba3YAl2O7.5: xTm3+ was prepared and the luminescent characteristic and thermal stability were studied. Under 358 nm excitation, the phosphors produced a blue emission peak centered at 461 nm, which is due to the transition of Tm3+ from level 1D2 to 3F4. Moreover, the optimal sample Ba3YAl2O7.5: 0.03Tm3+ shows an anti-thermal quenching effect in which the emission intensity at 210 °C rises to 120 % of that at 30 °C , attributable to the presence of oxygen vacancy defects. The result indicates that the Ba3YAl2O7.5: Tm3+ with excellent thermal stability is a promising blue phosphor for lighting and display fields.

Cation vacancy-boosted BaZnB4O8:xEu3+ phosphors with high quantum yield and thermal stability for pc-WLEDs.

Achieving high luminescent quantum yield and thermal stability of phosphors simultaneously remains challenging, yet it is critical for facilitating high-power white light emitting diodes (WLEDs). Herein, we report the design and preparation of the layered structure BaZnB4O8:xEu3+ (0.10 ≤ x ≤ 0.60) red phosphors with high quantum yield (QY = 76.5%) and thermal stability (82.8%@150 °C) by the traditional solid-state reaction method. The results of XRD and Rietveld refinement show that the presence of Eu3+ ions at Ba2+ sites causes the formation of cation (Zn2+/Ba2+) vacancies in the lattice. The PL and PL decay results reveal that the quenching concentration of BZBO:xEu3+ phosphors is as high as 50%, and the lifetime remains unchanged with Eu3+ concentration due to the unique structure of the host and the cation vacancies generated by the heterovalent substitution. Furthermore, on a 395 nm near-UV chip, a pc-WLED device with exceptional optical performance (CCT = 4415 K, CRI = 92.1) was realized using the prepared BZBO:0.50Eu3+ as a red phosphor. Simple synthesis and excellent performance parameters suggest that the reported BaZnB4O8:xEu3+ phosphors have promising applications in high-power pc-WLEDs. At the same time, it also indicates that cationic vacancy engineering based on heterovalent ion substitution is a potential strategy for improving luminescence quantum yield and thermal quenching performance.

Unusual red luminescence and super thermal stability of a new narrow-band emission phosphor for backlight display application

This work reports the design and successful synthesis of an Eu2+-doped narrow-band red-emitting borate phosphor, and proposes a defect engineering approach for enhancing the thermal quenching resistance of a phosphor.