Inorganic Luminescent Materials Research Articles

Suppressed concentration quenching and tunable photoluminescence in Eu2+-activated Rb3Y(PO4)2 phosphors for full-spectrum lighting

Highly efficient inorganic phosphors are desirable for lighting-emitting diode light sources, and increasing the doping concentration of activators is a common approach for enhancing the photoluminescence quantum yield (PLQY). However, the constraint of concentration quenching poses a great challenge for improving the PLQY. Herein, we propose a fundamental design principle by separating activators and prolonging their distance in Eu2+-activated Rb3Y(PO4)2 phosphors to inhibit concentration quenching, in which different quenching rates are controlled by the Eu distribution at various crystallographic sites. The blue-violet-emitting Rb3Y(PO4)2:xEu (x = 0.1%–15%) phosphors, with the occupation of Rb1, Rb2 and Y sites by Eu2+, exhibit rapid luminescence quenching with optimum external PLQY of 10% due to multi-channel energy migration. Interestingly, as the Eu concentration increases above 20%, Eu2+ prefer to occupy the Rb1 and Y sites with separated polyhedra and large interionic distances, resulting in green emission with suppressed concentration quenching, achieving an improved external PLQY of 41%. Our study provides a unique design perspective for elevating the efficiency of Eu2+-activated phosphors toward high-performance inorganic luminescent materials for full-spectrum lighting.

Novel Tm3+/Dy3+ co-doped CaMoO4 transparent glass-ceramic phosphor for white LED applications

To develop new inorganic luminescent materials, a set of Dy3+/Tm3+ co-doped molybdate precursor glasses (PGs) were manufactured using the conventional melting method, and a novel CaMoO4 transparent fluorescent glass-ceramic (GC700-2 h) was achieved via controlled crystallization of PG at 700 ℃ for 2 h. The luminescent color of the glass phosphor was facilely modulated by varying the doping levels of Dy3+ and Tm3+. The glass phosphor with optimal doping concentration of 0.6Dy3+ and 0.6Tm3+ exhibits a color coordinate of (0.3334, 0.3107). Compared with PG, the luminous intensity and quantum yield of GC700-2 h sample is obviously increased, and GC720-2 h sample displays the color coordinate (0.3292, 0.2852), belonging to the standard white light region. Moreover, GC720-2 h sample possesses good thermal stability in fluorescence property. The white LED lamp encapsulated with GC720-2 h exhibits color temperature of 7564 K and color rendering index of 75.3. These results clearly show that the 0.6Dy3+/0.6Tm3+ co-doped glass and CaMoO4 glass-ceramic could be used as potential candidate material in the field of white light-emitting diodes.

Achieving Multi-excitation in Lanthanide-based Cs2NaTbCl6:Ce/Yb Double Perovskite Single Crystals for Anti-counterfeiting

Lanthanide-doped inorganic perovskite luminescent materials have always been regarded as a good platform for multi-functional applications such as anti-counterfeiting and information encryption, owing to their good visibility, diverse colors and simple design. In this study, we design the Cs2NaTbCl6: Ce/Yb double perovskite single crystals, achieving visible green luminescence under various excitation sources such as ultraviolet, near-infrared (980 nm) and X-ray. The possible emission and energy transfer mechanisms between Tb3+ ions and Ce3+, Ce4+, Yb3+ ions under different excitations are discussed in detail. Our work skillfully takes advantage of the Tb3+ ions acquiring the transferred energy from non-luminescent Ce4+ ions and luminescent Ce3+ ions, broadening the ultraviolet response and improving its stability. The luminescence intensity of Cs2NaTbCl6 double perovskite single crystal was increased about 40 times under 343 nm excitation by doping Ce4+ and Ce3+ ions, which shows that Ce4+ and Ce3+ ions doping effectively introduces a new excitation band. Furthermore, diversified anti-counterfeiting modes are fabricated to highlight the promising applications of Cs2NaTbCl6 double perovskite systems with tunable luminescence in advanced anti-counterfeiting, paving the way for future research on the multi-light sources luminescent materials.

Ionic liquid-assisted preparation of Ag–Zn–In–S quaternary quantum dot thin films and luminescence performance optimized by machine learning

Machine learning-assisted synthesis of new materials has been an ongoing hot topic. Luminescent Ag–Zn–In–S quaternary semiconductor quantum dot thin films have great application potential in many fields because of their excellent photoelectric performance. In this study, an environmentally friendly ionic liquid-assisted approach was employed to prepare high-performance Ag–Zn–In–S luminescent thin films, and machine learning methods were applied to screen the optimal preparation conditions. The photoluminescence (PL) performance, crystal structure, and morphology of the thin films were also been studied. The initial data set was obtained by high-throughput experiments. By comparing machine learning algorithms of Xgboost, Random Forest, Bagging, SVM, Extra Tree, and Gradient Boosting, the Random Forest achieved the best accuracy (r = 0.84, R2 = 0.847) and was selected to predict the optimal preparation conditions of Ag–Zn–In–S quaternary quantum dot thin films. The machine learning predicted results are in great agreement with the subsequent experimental results, which verifies the accuracy and effectiveness of the machine learning model. This study offers a theoretical foundation for preparing optimal inorganic quantum dot luminescent materials using machine learning.

Lone‐Pair‐Driven, Brightly Emitting Lead‐Free Zero‐Dimensional Inorganic Luminescent Member

AbstractZero‐dimensional (0D) 5s2‐metal halide (MH) materials offer potential for use in solid‐state lighting, optical thermography, and scintillation applications. The organic components of most highly luminescent materials are inherently unstable under moisture and thermal stress, which restricts their practical use in advanced applications. Hence, highly luminescent and stable inorganic luminescent materials are required. In this work, to the best of current knowledge, a 0D completely inorganic luminescent member of K2SbCl5 that exhibits orange emission at 610 nm with an 80% photoluminescence quantum yield (PLQY) is reported for the first time. Density functional theory calculations reveal that the [SbCl5]2‐ square pyramidal units are the only optically active emission centers in K2SbCl5. The white light‐emitting device utilizing K2SbCl5 demonstrates impressive performance metrics, boasting a substantial color rendering index (CRI) of 94 and an exceptional luminous efficacy of 118.1 lm W−1. Hence, this isolated [SbCl5]2−square pyramidal environment serves as a design principle for the development of highly efficient inorganic Sb3+‐based luminescent materials for future optoelectronic applications.

Brighten strontium aluminate long-persistence materials via optimizing defect energy level distribution

Afterglow brightness of inorganic persistent luminescent (PersL) materials upon ceasing light excitation represents an important parameter for various glow-in-the-dark applications. Although the emission wavelength of PersL materials is developed to cover over the whole spectral range from ultraviolet to near infrared light, and light emission is sufficiently long-lasting with a fractional number of rare-earth doped PersL materials commercially available, PersL materials with high initial afterglow brightness at room-temperature condition remain rarely reported. Employing trap-controlled temperature dependency of persistent luminescence mechanism, defect energy level distribution, and microwave-assisted solid-state reaction, here a highly bright green-emitting strontium aluminate phosphor is reported. Higher initial afterglow brightness (a photometric luminance of 99.8 cd/m2, enhanced 1.7 times than that of the commercial one) is achieved due to the massive aggregation of charge carriers at shallow-trap energy levels. The relation between initial afterglow brightness and trap energy level distribution is investigated. The glowing-in-the-dark composite panel composed of Sr4Al14O25:Eu2+, Dy3+ and Polydimethylsiloxane can light up the safety sign and the map of fire evacuation route. These findings may provide a major step forward to developing high-brightness PersL materials and are expected to further benefit a wide range of PersL material systems for practical glow-in-the-dark applications.

Novel Red‐Emitting Gd3BW1‐xMoxO9 : Eu3+ Phosphor with High Thermal Stability for Application in UV‐Excited WLEDs and Rapid Visualization of Latent Fingerprints

AbstractRare‐earth‐doped inorganic luminescent materials are widely used in white light‐emitting diodes (WLEDs), lasers and forensic sciences due to their outstanding optical characteristics. However, it is still a challenge to obtain such materials with better thermal stability for application in WLEDs on account of their serious thermal quenching properties. In addition, there is still room for improvement in some respects such as higher sensitivity and contrast for application in latent fingerprint development. Herein, a series of novel Gd3BW1‐xMoxO9 : Eu3+ phosphors have been synthesized via high‐temperature solid‐state reaction process. Compared with different Mo6+ ions doping concentrations, Gd3BW0.7Mo0.3O9 : Eu3+ phosphor has optimal photoluminescence properties. Meanwhile, the emission intensity of Gd3BW0.7Mo0.3O9 : Eu3+ phosphor is over 3 times higher than that of commercial red phosphor. More impressive is its excellent resistance against thermal quenching; when heated up to 150 °C, the Gd3BW0.7Mo0.3O9 : Eu3+ phosphor still preserves about 98 % emission intensity of that at room temperature. Furthermore, the latent fingerprints (LFPs) developed by Gd3BW0.7Mo0.3O9 : Eu3+ phosphor exhibited the excellent visualization on various nonporous substrates, and level 1–3 features were well identified with high contrast and sensitivity. The obtained results suggested that the as‐prepared phosphor has great potential for application in both WLEDs and latent fingerprint detection.

All Inorganic Lead-Free Zero-Dimensional Metal Halide Luminescent Materials and Applications

Recently, zero-dimensional luminescent material has attracted researchers because of its optical properties, which is a possible candidate to replace lead halide perovskite. This review focused on the recent development of tetrahedrally and octahedrally coordinated inorganic halide semiconductor luminescent materials. We discuss the synthesis methods and crystal structures of these materials in this review. The materials are categorized based on the valence of central metal cations (monovalent, divalent, and trivalent). Finally, we have summarized the applications of these luminescent materials, such as light-emitting diodes, ultrafast switching memories, photodetectors, and scintillators. This review article provides an overview of recent progress on zero-dimensional materials and their applications for further development in the future.

Synergistic engineering of doping and vacancy in K0.5Na0.5NbO3-based photochromic ceramics to boost luminescent readout ability

Photon-mode ultracapacity storage media made of inorganic photochromic luminescent materials are highly anticipated, and widely explored in the development of new optical data storage (ODS) technologies. Despite some recent breakthroughs, the optical storage capacity of defect-rich photochromics is still limited to low luminescent readout abilities. Herein, oxygen vacancy rich and bismuth doped K0.5Na0.5NbO3:Eu3+ ceramics were designed, and synergistically boost the luminescence intensity, photochromic efficiency, and luminescent modulation properties, then effectively improving the luminescence readout abilities. The luminescence modulation ratio reaches up to 97.5% from 68.4% with the increase of oxygen vacancy concentrations due to hetero-valent bismuth doping, accompanied by high photochromic efficiency (35.7% from 21.9%) and excellent reproducibility. These results demonstrate that the synergistic engineering of oxygen vacancy and doping is a promising strategy for obtaining high-performance photochromic materials.

Synthesis and Luminescence Properties of Green-to-Red Color-Tunable Upconverting K2Gd(PO4)(WO4):Yb3+,Tb3+,Eu3+ Phosphors

Scientists are increasingly interested in new inorganic luminescence materials that could be excited with near-infrared (NIR) radiation. These materials can be used as luminescent thermometers, bio-imaging agents, anti-counterfeiting pigments, etc. In this manuscript, we report the synthesis and investigation of optical properties of two series of K2Gd(PO4)(WO4):20%Tb3+ (KGPW): the first, KGPW:20%Tb3+ doped with 1–20% Eu3+, and the second, KGPW:10%Yb3+,20%Tb3+ doped with 1–20% Eu3+. The phase-pure specimens were prepared using a solid-state synthesis method. Down-shifting and upconversion luminescence studies have been performed using 340 and 980 nm excitation, respectively. For upconversion emission luminescence, Yb3+ ions were used as sensitizers in the KGPW phosphors. In these phosphors, Yb3+ ions absorb the 980 nm radiation and transfer the energy to Tb3+ ions. At his point, Tb3+ ions either emit themselves or transfer part or all of their energy to Eu3+ ions. It was observed that the emission color of the synthesized phosphors could be successfully tuned from the green to red by varying the Tb/Eu concentration ratio regardless of the 340 or 980 nm excitation. Such color change proves that one luminescent material (KGPW) can provide three colors (i.e., green, orange, and red). Herein, the optical properties, such as reflection, down-shifting excitation and emission spectra, upconversion emission spectra, fluorescence lifetime, thermal quenching, color coordinates, and quantum efficiency, were studied using steady-state and kinetic spectroscopy.

Facile synthesis, novel structure, and tunable luminescence properties of K6Bi13(PO4)15:Dy3+,Eu3+ phosphors for ultraviolet converted white light-emitting diodes

A variety of novel Dy3+/Eu3+ mono- and co-doped K6Bi13(PO4)15 (KBPO) luminescent materials have been fabricated by a simple solid-state method for the first time. Both experimental studies and theoretical calculations verify that the K6Bi13(PO4)15 crystals are suitable to be utilized as host materials for the lanthanide activator ions. The XRD, EDS, and XPS results reveal that the Dy3+ and Eu3+ have been effectively incorporated into the KBPO host matrix and do not damage the structure of KBPO. The Dy3+ or Eu3+ mono-doped phosphors display the characteristic spectral patterns of the activator ions upon UV excitation whereas an energy transfer between Dy3+ and Eu3+ occurs which helps to obtain the tunable luminescence of the KBPO:Dy3+,Eu3+ phosphors. The emission colors of the KBPO:Dy3+,Eu3+ regularly shift from green-blue, through white, and finally toward yellow and orange-red by varying the activator doping concentrations under a fixed excitation wavelength. Interestingly, the single-phase white light emitting phosphors with CIE chromaticity coordinates of (0.3122, 0.3106) and (0.3602, 0.3246) are obtained by doping appropriate concentrations of Dy3+ and Eu3+, which match well with the standard white light illuminate of (0.333, 0.333). Moreover, the annealing conditions are optimized and the luminescent mechanisms and temperature-dependent luminescence performance are systematically investigated. Finally, the WLEDs device prepared by KBPO:Dy3+,Eu3+ phosphor and UV chip displays a dazzling white light with favorable CIE (Commission Internationale de I'Eclairage 1931 chromaticity) coordinates, color rendering index (Ra), correlated color temperature (CCT), and thermal stability, which provides direct evidence that the as-prepared inorganic luminescent materials may have prospects as an eminent single-phase white light emitting materials for white light-emitting diodes (WLEDs) and optoelectronic devices.

Optical Properties Investigation of Upconverting K2Gd(PO4)(WO4):20%Yb3+,Tm3+ Phosphors.

Nowadays, scientists are interested in inorganic luminescence materials that can be excited with UV or NIR radiation and emit in the visible range. Such inorganic materials can be successfully used as luminescent or anti-counterfeiting pigments. In this work, we report the synthesis and optical properties investigation of solely Tm3+ doped and Yb3+/Tm3+ co-doped K2Gd(PO4)(WO4) phosphors. The single-phase samples were prepared using a solid-state reaction method. The Tm3+ concentration was changed from 0.5% to 5%. Downshifting and upconversion emission studies were performed under 360 nm and 980 nm excitation, respectively. Yb3+ ions were used as sensitizers in the K2Gd(PO4)(WO4) phosphors to transfer the captured energy to Tm3+ ions. It turned out that under UV excitation, phosphors emitted in the blue spectral area regardless of the presence or absence of Yb3+. However, a very strong deep-red (~800 nm) emission was observed when Yb3+ and Tm3+-containing samples were excited with a 980 nm wavelength laser. It is interesting that the highest upconversion emission in the UV/Visible range was achieved for 20% Yb3+, 0.5% Tm3+ doped sample, whereas the sample co-doped with 20% Yb3+, 2% Tm3+ showed the most intensive UC emission band in the NIR range. The materials were characterized using powder X-ray diffraction and scanning electron microscopy. Optical properties were studied using steady-state and kinetic downshifting and upconversion photoluminescence spectroscopy.

Shortwave Infrared Luminescence of Tetravalent Chromium and Divalent Nickel: Phosphor Design Principles and Applications

Shortwave infrared radiations (SWIR, 900–1700 nm) emitting inorganic luminescent materials are key components for multiple applications, which range from optical communication and anticounterfeiting purposes to chemical and medical diagnosis. The blue light excitable SWIR phosphors activated with the transition metal ions Cr4+/Ni2+ are considered prospective light sources for an upcoming compact modern device using phosphor converter technology. In this review, the crystal field theory and Tanabe-Sugano diagram are briefly discussed to understand the splitting of energy levels and the concurrent effect. Several possible strategies to achieve and enhance the luminescence efficiency of Cr4+/Ni2+ SWIR emission are disclosed as is the reported chemical system. Finally, the domains for the potential practical application of SWIR phosphors are introduced. This review will provide information on the recent advances and the luminescence mechanism of Cr4+/Ni2+-activated SWIR phosphors and will also assist researchers in developing next-generation SWIR phosphors and exploring new applications.

Up-Converting K2Gd(PO4)(WO4):20%Yb3+,Ho3+ Phosphors for Temperature Sensing.

Inorganic luminescent materials that can be excited with NIR radiation and emit in the visible spectrum have recently gained much scientific interest. Such materials can be utilized as anti-counterfeiting pigments, luminescent thermometers, bio-imaging agents, etc. In this work, we report the synthesis and optical properties of K2Gd(PO4)(WO4):Ho3+ and K2Gd(PO4)(WO4):20%Yb3+,Ho3+ powders. The single-phase samples were prepared by the solid-state reaction method, and the Ho3+ concentration was changed from 0.5% to 10% with respect to Gd3+. It is interesting to note that under 450 nm excitation, no concentration quenching was observed in K2Gd(PO4)(WO4):Ho3+ (at least up to 10% Ho3+) samples. However, adding 20% Yb3+ has caused a gradual decrease in Ho3+ emission intensity with an increase in its concentration. It turned out that this phenomenon is caused by the increasing probability of Ho3+ → Yb3+ energy transfer when Ho3+ content increases. K2Gd(PO4)(WO4):20%Yb3+,0.5%Ho3+ sample showed exceptionally high up-conversion (UC) emission stability in the 77-500 K range. The UC emission intensity reached a maximum at ca. 350 K, and the intensity at 500 K was around four times stronger than the intensity at 77 K. Moreover, the red/green emission ratio gradually increased with increasing temperature, which could be used for temperature sensing purposes.

Opposite luminescence thermal behavior of upconversion core/shell nanocrystals for anticounterfeiting.

Inorganic luminescent materials generally suffer from thermal quenching due to accelerated nonradiative transitions at high temperature, whereas Yb3+ sensitized core nanocrystals with small sizes (<30 nm) exhibit a temperature-dependent upconversion luminescence (UCL) enhancement. The related mechanism of the anomalous UCL thermal behavior is still under debate. In this work, we find that the UCL of NaGdF4:Yb/Tm@NaGdF4 inert-shell nanocrystals declines at elevated temperature, while that of NaGdF4:Yb/Ho@NaGdF4:Yb active-shell ones is enhanced. The thermally-induced UCL enhancement of active-shell nanocrystals is attributed to a gradually attenuated surface quenching effect. The initiators of the surface quenching are H2O molecules, which mainly attenuate Yb3+ excited states through an overtone energy transfer. The energy transfer is a coupling effect between ion dipoles of Yb3+ and atomic dipoles of H2O. Utilizing the opposite UCL temperature-dependence of active- and inert-shell nanocrystals, we designed their hybrids, which exhibit temperature-responsive multicolor emissions. The color-tunable hybrids are demonstrated to be excellent candidates for producing anticounterfeiting patterns with high security but simple recognition methods.

Engineering luminescence switching and photochromic performance in tungsten bronze oxides for handwriting display based on variable valence ion strategy

Inorganic luminescence materials with intelligent response to external stimuli have drawn considerable interest owing to their alluring applications. Photochromic (PC) is a reversible process which can be adopted to construct subtle luminescence regulation. However, the PC effect is commonly weak for most inorganic materials. It is still challenging to realize strong luminescence switching and PC effect in general inorganic compounds. To fill this gap, tetragonal tungsten bronze (TTB) oxides with ingenious upconversion (UC) luminescence modulation and prominent PC phenomenon were designed by introducing variable valence ion (Mo6+). Under this decorating, the UC luminescence switching ratio and PC contrast could be increased up to 2 and 4 times, respectively. The real-time information encoding based on PC and UC modulation was realized in TTB wafer, confirming the instant handwriting dual-mode display capacity. It is believed that this work will shed new light on the designing of terminal display devices.

Effect of grain size on macroscopic flexibility and luminescence intensity of inorganic (Ba,Ca)TiO3:Pr3+

Traditional inorganic ceramic materials usually exhibit macroscopic rigidity due to the incompatibility to the flexibility mechanism of traditional flexible materials such as sliding of polymer chains or atoms. Recently, new form of nanotechnology has been proposed to be capable of preparing inorganic flexible materials. In this paper, inorganic luminescent material (Ba,Ca)TiO3:Pr3+ was prepared into the flexible form by electrospinning technology, and the macroscopic flexibility of pure inorganic (Ba,Ca)TiO3:Pr3+ was systematic investigated. The crystal grain size was found to grow after higher temperature calcination, which benefits luminescence. However, lowering the calcination temperature will further optimize the flexibility of the membrane. This study shows that fibrous membrane fabrication is an applicable flexible fabrication strategy for inorganic oxides, which provides an important reference for the design of flexible materials.

CaGdAl3O7:Eu3+ unidimensional nanostructures: Facile electrospinning synthesis, structure and luminescence

Inorganic luminescent materials with special unidimensional morphologies have become one kind of highly promising materials in luminescence field. Here, CaGdAl3O7:Eu3+ unidimensional nanostructures containing nanofibers, nanobelts and hollow nanofibers are fabricated perfectly via facile mono-axial electrospinning technology combined with subsequent oxidation procedure. The formation mechanisms of CaGdAl3O7:Eu3+ unidimensional nanostructures have been put forward and a new technology of constructing the unidimensional nanostructures is given. The morphologies of nanofiber, nanobelt and hollow nanofiber can be easily modulated via regulating the components of spinning solution and spinning parameters. CaGdAl3O7:Eu3+ unidimensional nanostructures are tetragonal in structure with space group of P‾ 421m and possess perfect unidimensional morphologies. The unidimensional nanostructures show the predominant emissions at 590 and 619 nm under 256-nm ultraviolet light excitation, which result from 5D0→7F1 and 5D0→7F2 transitions of Eu3+ ions, respectively. The luminescence properties of the nanostructures can be adjusted by altering Eu3+ content, calcination temperatures and morphologies of the nanostructure. In brief, this work is of great significance for follow-up investigations of melilite group aluminates luminescence nanomaterials with distinct unidimensional morphologies.

Rapid Aqueous-Phase Synthesis and Photoluminescence Properties of K0.3Bi0.7F2.4:Ln3+ (Ln = Eu, Tb, Pr, Nd, Sm, Dy) Nanocrystalline Particles

Trivalent lanthanides (Ln3+) doped bismuth-based inorganic compounds have attracted considerable interest as promising candidates for next-generation inorganic luminescent materials. Here, a series of K0.3Bi0.7F2.4 (KBF) nanocrystalline particles with controlled morphology have been synthesized through a low-temperature aqueous-phase precipitation method. Using KBF as the host matrix, Eu3+, Tb3+, Pr3+, Nd3+, Sm3+, and Dy3+ ions are introduced to obtain K0.3Bi0.7F2.4:Ln3+ (KBF:Ln) nanophosphors. The as-prepared KBF:Ln nanophosphors exhibit commendable photoluminescence properties, in which multicolor emissions in a single host lattice can be obtained by doping different Ln3+ ions when excited by ultraviolet light. Moreover, the morphology and photoluminescence performance of these nanophosphors remain unchanged under different soaking times in water, showing good stability in a humid environment. The proposed simple and rapid synthesis route, low-cost and nontoxic bismuth-based host matrix, and tunable luminescent colors will lead the way to access these KBF:Ln nanophosphors for appealing applications such as white LEDs and optical thermometry.

Broadband Near-Infrared-Emitting Phosphors with Suppressed Concentration Quenching in a Two-Dimensional Structure

For inorganic luminescent materials with activators, the energy yield is usually observed to decrease with an increase in activator concentration, which is known as the concentration quenching effect. To inhibit this phenomenon, a common strategy is to increase the distance between activators. Most previous reports have focused on the three-dimensional crystal lattice, and there have been few reports about two-dimensional layered structure. Herein, we synthesized a novel Cr3+-activated near-infrared (NIR) phosphor Li2Sr2Al(PO4)3 (LSAPO) with layered structure, and in such a two-dimensional structure, we proved experimentally that the concentration quenching was suppressed. Under 460 nm excitation, LSAPO:Cr3+ gave a broad NIR emission band (700-1200 nm) centered at 823 nm with a full width at half-maximum (fwhm) of 178 nm and a broad absorption band, indicating its potential application in NIR spectroscopy. Moreover, by codoping Cr3+ and Yb3+ ions, we further widened the emission bandwidth to ∼230 nm of fwhm, the internal quantum efficiency increased from 54% to 61%, and the thermal stability was improved. The fabricated NIR device with a LSAPO:Cr3+,Yb3+ phosphor coupled with blue chips can be applied in night-vision technologies and medical fields.