White Light-emitting Diodes Research Articles

Realization of narrow-band blue emission based on structurally engineering-designed Bi3+-doped phosphors

The exploration of efficient narrowband emission phosphors is crucial for white light-emitting diodes (WLEDs) in high-performance backlighting applications. Up to now, the discovery of narrow-band Bi3+-doped phosphors for emerging applications remains challenging because Bi3+ typically exhibits broadband emission properties. A novel narrow-band blue phosphor (Ca4SnGe3O12:Bi3+) was successfully synthesized, benefiting from the highly symmetric crystal environment and tightly connected rigid structure of the garnet structure. The phosphor demonstrates broad excitation in the near-ultraviolet (n-UV) region and emits narrowband blue light at 442 nm (FWHM = 36 nm) with a color purity of 94.7 %. In this paper, the assignment of different luminescence centers and the use of Zr/Hf to partially replace Sn to enhance luminescence performance are studied. The reasons for the consequent changes in luminescence behavior are explained in detail. The use of narrowband commercial red K2SiF6:Mn4+, green β-Sialon:Eu2+, and synthetic blue luminescent materials as RGB emitters covered 81 % of the National Television System Committee (NTSC) color space, demonstrating great potential for liquid-crystal-display (LCD) backlight use.

Mixed former effect in barium borophosphate glasses on the red (Eu3+)-blue (Eu2+) emission for LEDs

The synergistic mixing of P2O5 and B2O3 glass formers at a constant concentration of BaO as a glass modifier plays a vital role in generating a single-phase phosphor doped with Eu2O3 for white light-emitting diodes (WLEDs). Herein, a glass system of nominal composition xP2O5∙(50-x)B2O3∙49.5BaO∙0.5Eu2O3 (0 ≤ x ≤ 50 mol%) was prepared using a melt-quenching technique under normal atmospheric conditions. While the XRD patterns demonstrated the amorphous nature, the SEM micrographs proved the formation of cluster structures. Structural characterization using ATR-FTIR spectroscopy revealed the presence of main vibrational structural units associated with borate and phosphate glass formers, including BO3, BO4−, P=O, PO2−, and PO32−. The IR spectra at x = 0 and 50 mol% exhibit characteristic metaborate and metaphosphate absorption peaks, respectively. In contrast, the mixing of both B2O3 and P2O5 at equal concentrations (x = 25 mol%) has resulted in the absence of absorption peaks assigned to the BO3 and P=O units, thus indicating the mixed structural effect. This is assigned to the formation of B-O-P bonds, with the BO4−, PO2−, and PO32− as the main structural units. These structural changes affect the reduction process of Eu3+ to Eu2+, as demonstrated by the corresponding photoluminescence spectra and observed by the cathodoluminescence micrographs. Photoluminescence studies showed tunable emission from red (Eu3+) to white light (Eu2+ and Eu3+) under UV excitation, with the P2O5 content rising from 0 to 50 mol% due to the growing Eu2+ population formed by the reduction of Eu3+. The optical basicity was observed to decrease with the P2O5 content, favouring the reduction process. The demonstrated tunable single-host white phosphor makes this an attractive system for energy-efficient WLED applications.

Investigative photometry experiments on planar extended-light sources

The inverse-square decay law of the illuminance of a point light source with distance is a common notion of basic optics theory, which is readily demonstrated to be a direct consequence of the propagation of spherical wave fronts with the centre at the light source. It is far less common to address the experimental verification of this law and, even less, to study the illuminance decay with the distance of extended light sources, which somehow represent an unknown topic. We propose a scientific experiment where the light sensor of a smartphone is used to collect illuminance data as a function of the source-to-sensor distance and orientation. Through this procedure, students can realize the limit of validity of the inverse-square law and determine the luminance flux of the chosen point-like light source (e.g. the white LED flashlight of a smartphone). More interestingly, when dealing with extended sources (e.g. the LCD of a laptop displaying a white image) subtle characteristics of the decay trend emerge, particularly for distances lower that the source size. A detailed analysis of these characteristics is presented though a process allowing student engagement in a real scientific investigation, envisaging steps of data acquisition through experimental measurements, model construction on the basis of the observed patterns, and finally model testing. We provide a guided formulation for the general modelling of planar emitters, starting from the theoretical treatment of Lambertian sources. In this way, students are able to quantify the luminous emission also for extended sources and their deviation from a Lambertian behaviour.

A thermally stable narrow-band green phosphor Na2MgAl10O17: Eu2+, Mn2+ for NUV LED application

Thermally stable narrow-band green phosphor is important for phosphor-converted light emitting diodes (pc-LEDs). Herein, an efficient and stable Na2MgAl10O17: Eu2+, Mn2+ green phosphor is obtained using Eu2+-Mn2+ energy transfer strategy. The Mn2+ activator could be effectively sensitized by the addition of Eu2+ with significant UV absorption enhancement, then generates a bright green emission with peak at 515 nm and FWHM of 40 nm. The internal and external quantum efficiencies of optimal phosphor Na2MgAl10O17: 0.15Eu2+, 0.50Mn2+ are measured as 69.5 and 30.8 %, respectively. It is found that Na2MgAl10O17: Eu2+, Mn2+ phosphor shows good chemical and thermal stability, i.e. maintains no quenching after H2O/HCl soaking and keeps 90 % of RT intensity at 200 °C. By using Na2MgAl10O17: Eu2+, Mn2+ as converted phosphor, single-chromatic and white pc-LEDs were fabricated, which simultaneously achieve green and white emission with high brightness. Our results show that this Na2MgAl10O17: Eu2+, Mn2+ is a potential candidate as a thermally stable green phosphor for white LEDs.

Investigation of the temperature-dependent photoluminescence characteristics in Mn2+-doped (PEA)2PbBr4 perovskite

The two-dimensional organic-inorganic hybrid perovskites demonstrate significant potential for use in photodetectors and white light-emitting diodes. In this study, we successfully synthesized pure and Mn2+-doped (PEA)2PbBr4 perovskite via rapid crystallization. The morphology, structure, magnetic properties, and optical characteristics of them were comprehensively characterized. The unusual behavior of free exciton emission is mainly attributed to electron-phonon coupling and negative thermal quenching effects. The self-trapped exciton emission results from self-trapped excited states and electron-phonon coupling. Moreover, energy transfer phenomena are observed between free exciton emission, self-trapped exciton emission, and Mn2+ emission. These findings offer valuable insights into the luminescence mechanism of two-dimensional layered perovskites.

Realizing Stable Luminescence in Antimony Doped Hybrid Tin(IV) Chloride toward Full Spectrum WLED and Anticounterfeiting Applications.

The outstanding optical properties empower Sb3+-doped zero-dimensional hybrid metal halides as cutting-edge luminescent materials. In this research, we present an efficient hybrid tin chloride, TEA2SnCl6:Sb3+ (TEA = tetraethylammonium), with broad dual emission bands peaking in the blue and orange regions that arise from the singlet and triplet state emissions of [SbCl5]2-, respectively. TEA2SnCl6:Sb3+ demonstrates a high photoluminescence quantum yield (PLQY) of 83.5% under 328 nm excitation, while 358 nm light induces an orange emission with a PLQY of 92.5% and a low thermal quenching behavior (73.9% at 423 K). Benefiting from the appealing luminescence properties of TEA2SnCl6:Sb3+, a full spectrum white light-emitting diode (WLED) device and an anticounterfeiting model were constructed, affirming the potential use of Sb3+-doped TEA2SnCl6 hybrid metal halide in versatile application fields.

A samarium (Ⅲ)-activated tantalum-based double perovskite phosphor with high thermostability

Inorganic double perovskite phosphor materials have received much attention in solid-state lighting domain due to efficient and versatile luminescence colors. This study employs a high-temperature solid-phase method to synthesize a series of Sm3+-activated Sr2YTaO6 (SYTO):Sm3+ phosphors with double perovskite structure. The structure, morphology, and content/temperature-dependent orange-red emissions are thoroughly elucidated. For SYTO:3 mol%Sm3+, the luminescence intensity at 423 K remains 95 % of that at 298 K, verifying high thermostability. Meanwhile, the phosphor exhibits good resistance to color shifting. A high Sm3+ content induces luminescence quenching due to dipole–dipole interaction. Finally, the synthesized material is utilized to fabricate a satisfactory and warm white light-emitting diode.

Microwave-assisted in-situ synthesis of low-dimensional perovskites within metal-organic frameworks for optoelectronic applications

Halide perovskites are renowned for their remarkable optoelectronic properties, yet their application is hindered by stability challenges. Metal-organic frameworks (MOFs) have emerged as promising matrices for enhancing perovskite durability. In this study, we achieved the in-situ synthesis of a series of perovskites within the MOF-5 matrix, spanning three-dimensional, quasi two-dimensional, and two-dimensional structures, via microwave-assisted reaction techniques. This microwave synthesis method has proven to be a rapid and efficient approach for the high-yield production of perovskite materials. These MOF-5⊃perovskites exhibited superior optical properties, positioning them as promising candidates for various optoelectronic applications, including white light-emitting diodes and optical wireless communication (OWC) systems. Significantly, our perovskites demonstrated high and consistent communication rates, making them suitable for both space and underwater OWC deployments. Overall, our study underscores the potential of microwave-assisted synthesis in advancing high-performance perovskite materials, offering valuable insights for the development of future optoelectronic devices.

Investigation on luminescent characteristics of Tb3+/Dy3+co-doped boro-phosphate glass for cool white LED and radiation shielding applications

The Tb3+/Dy3+ co-doped Boro-Phosphate Glass (BPANZDyTb) was produced (40 B2O3 + 39P2O5 + 5 Al2O3 + 5 NaF + 10 ZnO + 0.5 Tb2O3 + 0.5 Dy2O3) using melt-quenching technique. X-ray diffraction measurements, Raman, and Fourier Transform Infrared were used to evaluate the structural behavior of the prepared glass. Powder-XRD spectra, in the 10–90° range showed that the prepared glass was amorphous. FTIR analysis reveals that the network contains a variety of structural groups, including B-O-B, BO4, BO, P-O, PO2, P-O-B, and PO4 units. The UV–visible diffuse reflectance spectroscopy was used to record and study the optical linear properties of Tb3+/Dy3+ co-doped Boro-Phosphate Glass (BPANZDyTb). The photoluminescence excitation peak was obtained at 348 nm. The emission peaks were located at 484 nm (4F9/2 → 6H15/2 → blue), 576 nm (4F9/2 → 6H13/2 → yellow), and 662 nm (4F9/2 → 6H11/2 → red). Tb3+ ions are located at 412 nm (5D3 → 7F5), 441 nm (5D3 → 7F4), 546 nm (5D4 → 7F5), and 625 nm (5D4 → 7F3). The result of CIE 1931 chromaticity coordinates indicate that the prepared glass is suitable material for cold white light emitting diode applications due to its color coordinates x = 0.3106 and y = 0.3240 and correlated color temperature (CCT) values about 6768 K. The gamma-ray parameters such as half-value layer (HVL), mass attenuation coefficient (μ/ρ), mean free path (MFP), and effective atomic number (Zeff) of the BPANZDyTb glass were studied using Phy-X software. The results of the gamma-ray parameter show that the Dy3+ ions and Tb3+ ions co-doped BoroPhosphate glass is an appropriate material for radiation shielding applications.

Research on CdSe/ZnS Quantum Dots-Doped Polymer Fibers and Their Gain Characteristics.

Polymer fibers are considered ideal transmission media for all-optical networks, but their high intrinsic loss significantly limits their practical use. Quantum dot-doped polymer fiber amplifiers are emerging as a promising solution to this issue and are becoming a significant focus of research in both academia and industry. Based on the properties of CdSe/ZnS quantum dots and PMMA material, this study experimentally explores three fabrication methods for CdSe/ZnS quantum dots-doped PMMA fibers: hollow fiber filling, melt-drawing, and melt extrusion. The advantages and disadvantages of each method and key issues in fiber fabrication are analyzed. Utilizing the CdSe/ZnS quantum dots-doped PMMA fibers that were fabricated, we theoretically analyzed the key factors affecting gain performance, including fiber length, quantum dots doping concentration, and signal light intensity. Under the conditions of 1.5 W power and 445 nm laser pumping, a maximum on-off gain of 16.2 dB was experimentally achieved at 635 nm. Additionally, using a white light LED as the signal source, a broadband on-off gain with a bandwidth exceeding 70 nm and a maximum gain of 12.4 dB was observed in the 580-650 nm range. This research will contribute to the development of quantum dots-doped fiber devices and broadband optical communication technology, providing more efficient solutions for future optical communication networks.

Local structure engineering of Ba1-xKxLa2Y2(SiO4)2O1-α: Eu2+ green phosphors for violet-light-excitable full-spectrum lighting

To achieve comfortable and healthy full-spectrum lighting, the development of efficient and stable violet-light-excitable phosphors is urgently required. Herein, we report a new type of green-emitting phosphor, Ba1-xKxLa2Y2(SiO4)2O1-α: Eu2+ (x=0–1). Interestingly, K+-alloying leads to continuous redshift of green emission from 500 nm to 517 nm accompanied with reduced full width at half maximum (FWHM) from 72 nm to 63 nm and enhanced excitation intensity in the violet spectral region. Rietveld refinements and spectral analysis evidence that K+-addition enhances the distortion of [M(Ⅰ)O9] and [M(Ⅱ)O7] (M(Ⅰ/Ⅱ) = Ba, La, Y, K) polyhedron and strengthens crystal field around Eu2+, which is responsible for the observed photoluminescence (PL) phenomenon. Finally, we design a full-spectrum white light emitting diode (WLED) with an ultra-high color rendering index (CRI, Ra) of 97.4 by coupling the as-prepared green-emitting phosphor (Ba0.7K0.3La2Y2(SiO4)2O1-α: Eu2+) and commercial blue/red phosphors with a violet LED chip, which demonstrates significant potential for application in healthy solid-state lighting.

Rare earth Nd3+-doped organic-inorganic hybrid perovskite quantum dots for white LED

Lead halide perovskite quantum dots (QDs) have garnered significant attention due to their tunable band gaps, unique quantum confinement effects, and high photoluminescence quantum yields (PLQYs). Among them, Organic-inorganic QDs make them promising candidates for optoelectronic devices such as quantum dot light-emitting diodes (QLEDs), solar cells, lasers, and photodetectors. However, the toxicity of lead (Pb) has raised environmental and health concerns, hindering their industrial application. To alleviate concerns about heavy metals Pb, extensive research has been conducted on B-site doping and the development of lead-free perovskites. Herein, we firstly developed B-site doping strategy on organic-inorganic hybrid perovskite QDs via rare-earth elements. Neodymium (III) (Nd3+) doped FAPbBr3 QDs were prepared through the ligand-assisted reprecipitation method at room temperature. The B-site doping strategy could alleviate the heavy metal problem of Pb and modulate the band gap of FAPbBr3 QDs facilely. The results demonstrated that increasing the concentration of Nd³⁺ can change the emission of FAPbBr₃ QDs from pure green to deep blue. Specifically, we achieved highly pure blue emission (∼438 nm) with a full width at half maximum (FWHM) of 13 nm for Nd³⁺-doped FAPbBr₃ QDs. Time-resolved photoluminescence (TRPL) spectroscopy revealed a decrease in the lifetime of FAPbBr₃ QDs from 22.86 to 15.46 ns as the doping concentration increased. Additionally, we fabricated a white LED (WLED) utilizing blue-emitting Nd³⁺-doped FAPbBr₃, green-emitting FAPbBr₃ QDs, and red QDs, achieving a white emission color coordinate of (0.33, 0.36). This study pioneers the application of B-site rare-earth doping in organic-inorganic hybrid perovskite QDs, demonstrating that B-site composition engineering is a reliable strategy to further exploit the perovskite family for wider optoelectronic applications.

Efficient blue light emission induced by the Cu-doping in Cs2ZnI4 for white light-emitting diodes

Zinc halides have attracted much interest because of their unique structures, non-toxicity and low cost among lead-free halides. In this work, we studied the crystal structures and luminescence properties of Cu-doped Cs2ZnI4 (Cs2Zn1-xCuxI4-x, x = 0.01–0.15). The pristine Cs2ZnI4 has no luminescence properties under ultraviolet light irradiation, while the Cu-doped ones emit blue lights. With the increase of the doping level, the luminescence peak of as-fabricated samples gradually shifted from 476 nm to 450 nm. Detailed experimental characterization and theoretical calculations demonstrate that the emission of blue light originates from the mechanism of self-trapped exciton. A phosphor-converted white light-emitting diode fabricated with Cs2Zn0.9Cu0.1I3.9 exhibits a high color rendering index of 94.2 and remains stable when adjusting the operating current. This work reports Cs2ZnI4 as a new phosphor, demonstrating the potential application of the zinc family for the field of solid-state lighting.

Ostwald ripening inhibition by a bipolar ligand achieves long-term-reaction and scalable synthesis of ultra-stable CsPbX3 perovskite quantum dots towards LEDs

All-inorganic perovskite quantum dots (PeQDs) hold immense potential for use in light-emitting diodes (LEDs) due to their excellent optoelectronic properties. However, the scalable synthesis and poor stability have severely hindered their application. Here, we solved both the two issues with “one stone”, namely a bipolar ligand 3-(N,N-dimethyloctadecylammonio) propane sulfonate (ASC18). ASC18 contains a positively charged quaternary ammonium group and a negatively charged sulfonic group, which enables for long-term reaction and gram-level synthesis of PeQDs with outstanding morphology, crystallinity, and optical properties. Density functional theory calculations and experimental studies show that these merits arise from the inhibition of Ostwald ripening by ASC18 due to their simultaneous interaction with undercoordinated Br– and Pb2+ via a bidentate binding mode. Furthermore, ASC18 capped PeQDs present significantly improved stabilities against air, UV irradiation, heat, and polar solvent. Finally, both electroluminescent LEDs and down-conversion white LEDs fabricated with our PeQDs show significant operational stability. This presents a trustworthy avenue to obtain high-quality PeQDs for their practical applications.

Dual-functional application of Ca2Ta2O7:Bi3+/Eu3+ phosphors in multicolor tunable optical thermometry and WLED

A series of Bi3+/Eu3+ co-doped Ca2Ta2O7 (CTO:Bi3+/Eu3+) phosphors were prepared by high-temperature solid-state method for dual-emission center optical thermometers and white light-emitting diode (WLED) device. By modulating the doping ratio of Bi3+/Eu3+ and utilizing the energy transfer from Bi3+ to Eu3+, the tunable color emission ranging from green to reddish-orange was realized. The designed CTO:0.04Bi3+/Eu3+ optical thermometers exhibit significant thermochromism, superior stability, and repeatability, with maximum sensitivities of Sa = 0.055 K−1 (at 510 K) and Sr = 1.298% K−1 (at 480 K) within the temperature range of 300−510 K, owing to the different thermal quenching behaviors between Bi3+ and Eu3+ ions. These features indicate the potential application prospects of the prepared samples in visualized thermometer or high-temperature safety marking. Furthermore, leveraging the excellent zero-thermal-quenching performance, outstanding acid/alkali resistance, and color stability of CTO:0.04Bi3+/0.16Eu3+ phosphor, a WLED device with a high Ra value of 95.3 has been realized through its combination with commercially available blue and green phosphors, thereby demonstrating the potential application of CTO:0.04Bi3+/0.16Eu3+ in near-UV pumped WLED devices.Graphical abstract

Performance improvement of ZnO quantum dot-based white light-emitting diodes enabled by an insulating passivation interlayer

In this work, solution-processed white quantum dot light-emitting diodes (WQLEDs) were demonstrated by using the zinc oxide quantum dots (ZnO-QDs) as both a white fluorescent emitter as well as an effective electron injection layer. Meanwhile, a thin insulating passivation layer of polystyrene (PS) was inserted between the ZnO-QDs layer and aluminum cathode to optimize the electron injection into the device and reduce the non-radiative recombination at the interface between ZnO-QDs layer and cathode. Our findings reveal that strategically incorporating a thin PS insulating passivation interlayer between the ZnO-QDs and the aluminum cathode effectively reduces the surface defects of the ZnO-QDs as well as the infiltration of metal atoms into the ZnO-QD layer. Consequently, the WQLEDs with such an insulating PS interlayer exhibit a high brightness of 1076 cd/m2, showing a great improvement of∼40 % compared with that of WQLEDs without PS passivation interlayer (780 cd/m2). This work provides an efficient method to realize single component WQLEDs, thus bringing a feasible solution for next-generation solid-state lighting technologies.

Light Spectra, a Promising Tool to Modulate Ulva lacinulata Productivity and Composition.

Light quality is a key factor affecting algal growth and biomass composition, particularly pigments such as carotenoids, known for their antioxidant properties. Light-emitting diodes (LEDs) are becoming a cost-effective solution for indoor seaweed production when compared to fluorescent bulbs, allowing full control of the light spectra. However, knowledge of its effects on Ulva biomass production is still scarce. In this study, we investigated the effects of LEDs on the phenotype of an Ulva lacinulata strain, collected on the Northern Portuguese coast. Effects of white (W), green (G), red (R), and blue (B) LEDs were evaluated for growth (fresh weight and area), photosynthetic activity, sporulation, and content of pigments and antioxidant compounds. The results showed that there were no significant differences in terms of fresh weight accumulation and reduced sporulation among the tested LEDs, while W light induced the highest expansion rate. Under G, U. lacinulata attained a quicker photoacclimation, and the highest content of pigments and total antioxidant activity; but with R and W, antioxidant compounds against the specific radicals O2•- and •NO were produced in a higher content when compared to other LEDs. Altogether, this study demonstrated that it is possible to modulate the bioactive properties of U. lacinulata by using W, R, and G light, opening the path to the production of biomass tailored for specific nutraceutical applications.

Modifying the Ambient Light Spectrum Using LED Lamps Alters the Phenolic Profile of Hydroponically Grown Greenhouse Lettuce Plants without Affecting Their Agronomic Characteristics.

The growth and development of green lettuce plants can be modulated by the prevailing light conditions around them. The aim of this study was to evaluate the effect of ambient light enrichment with different LED light spectra on agronomic characteristics, polyphenol concentration and relative gene expression of enzymes associated with polyphenol formation in 'Levistro' lettuce grown hydroponically in a Nutrient Film Technique (NFT) system for 28 days in a greenhouse. The spectra (blue:green:red:far-red) and red:blue (R:B) ratios obtained by enriching ambient light with Blue (B), White (W), Blue-Red (BR) and Red (R) LED light were B: 47:22:21:10, 0.5:1; W: 30:38:23:9, 0.8:1; BR: 33:15:44:8, 1.3:1 and R: 16:16:60:8, 3.8:1, respectively, and photosynthetically active radiation (PAR) under the different treatments, measured at midday, ranged from 328 to 336 µmoles m-2 s-1. The resulting daily light integral (DLI) was between 9.1 and 9.6 mol m-2 day-1. The photoperiod for all enrichment treatments was 12 h of light. The control was ambient greenhouse light (25:30:30:15; R:B = 1.2:1; PAR = 702 µmoles m-2 s-1; DLI = 16.9 mol m-2 day-1; photoperiod = 14.2 h of light). Fresh weight (FW) and dried weight percentage (DWP) were similar among the enrichment treatments and the control. The leaf number increased significantly under BR and R compared to B lights. The relative index of chlorophyll concentration (RIC) increased as plants grew and was similar among the enrichment treatments and the control. On the other hand, the concentration of chlorogenic acid and chicoric acid increased under BR and B lights, which was consistent with the higher relative expression of the coumarate 3-hydroxylase enzyme gene. In view of the results, it is inferred that half of the PAR or DLI is sufficient to achieve normal growth and development of 'Levistro' lettuce plants, suggesting a more efficient use of light energy under the light enrichment treatments. On the other hand, the blue and combined blue-red lights promoted the accumulation of phenolic compounds in the leaves of 'Levistro' lettuce plants.

Warm white light emitting thermally stable Dy3+ activated antimony fluoroborate glasses for n-UV based white LEDs

A transparent series of trivalent dysprosium (Dy3+) ions activated calcium antimony fluoroborate glass samples (CAFB) were synthesized by the aid of the melt quenching process. The thermogravimetric, structural, and spectroscopic characterizations were evaluated and investigated in detail. Thermogravimetric analysis was performed to determine the glass transition temperature Tg and crystallization temperature (Tc) of the prepared host CAFB glass. Raman Spectroscopy and Fourier transform infrared (FT-IR) analyzed the structural orientation as well as bonding formation in the prepared CAFB host and CAFBDy1.0 glass matrix. Furthermore, the optical absorption spectra exhibit various absorption peaks between the n-UV to NIR region (350 to 2000 nm). Under the different n-UV excitation wavelengths, photoluminescence (PL) spectra reflect three foremost emission centres located around 482, 575, and 663 nm in the Dy3+: CAFB glasses. The observed colour coordinates of the prepared CAFBDy glasses were marked in the standard white area of the CIE chart under different n-UV excitation wavelengths. Moreover, temperature-dependent PL (TDPL) studies demonstrate that these glass samples have significant thermal stability and also a large activation energy. Hence, the above-mentioned results prove the versatility of the CAFBDy glasses to make them potential candidates for usage in luminescent device applications.

Rational Synthesis of Single-Component White-Light-Emitting Carbon Nanodots for Warm White LEDs with a High Color Rendering Index of 95.4

Rational Synthesis of Single-Component White-Light-Emitting Carbon Nanodots for Warm White LEDs with a High Color Rendering Index of 95.4