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Two hybrid chloroantimonates(III), [Bzmim]3SbCl6 (1, Bzmim=1‐benzyl‐3‐methylimidazolium, Tm1=410 K) and [Bzmim]2SbCl5 (2, Tm2=348 K) are presented. 1 exhibits green emission (quantum efficiency of 87.5 %); 2 exhibits blue and red emissions under the irradiation of 310 and 396 nm light, respectively. Using different cooling methods, crystalline 1 and IL@2 (IL=ionic liquid of [Bzmim]Cl) could be generated from the molten 1. Reversible structural and PL transformation triggered by moisture or heat was observed between 1 and IL@2. Such PL switching, combined with the crystallization‐induced PL properties of 1 and 2, resulted in the firstly reported triple‐mode reversible PL switching, that is, on–off (T>Tm1), color switching (T

Blue phosphorescent materials typically have larger capacitance compared with commercialized blue fluorescent OLEDs. To improve capacitance‐related image quality issues, we need to reduce capacitance of devices without sacrificing other device's properties such as efficiency, lifetime, and operating voltage. In this study, we analyzed devices with phosphor sensitized TADF (PST) emission devices by impedance spectroscopy and revealed that the capacitance is largely affected by giant surface potential (GSP) of consisting layers. The influence of GSP on capacitance is sensitively changed by not only GSP value but also the position of GSP layers in the device. We revealed the effect of GSP of HTL, BIL etc. and explained the mechanism underlying on this phenomena based on device simulation. [ABSTRACT FROM AUTHOR]

Perovskite nanocrystals (PeNCs) are promising color converters due to their high blue light absorption and narrow‐band emission. This paper reports on the bright and stable PeNCs inks for patterned green/red color conversion pixels. Inks designed to stabilize PeNCs have a shelf life of more than one month, and UV‐cured PeNCs films exhibit high color conversion efficiency and practical durability to blue light and heat. Our PeNCs inks are capable of sufficient color conversion even at high pixel resolutions and will be a viable solution for full‐color OLED and micro‐LED displays. [ABSTRACT FROM AUTHOR]

A paper web produced under industrial conditions always exhibits an anisotropy in its mechanical properties measured in the machine and cross directions. Proper and fast information about current paper anisotropy would significantly increase the efficiency of web quality control systems and allow to produce paper with greater precision. The main objective of the work presented was to determine the possibility of measurement of paper anisotropy. The method proposed is based on the image analysis of the orientation and location of special markers -- luminescent fibres -- which were introduced to the structure of the paper. Studies have shown that the method of image analysis provides a detection of fibres with a satisfactory level of efficiency, thus allowing accurate examination of the anisotropy of the paper samples analysed. On the basis of experiments, it was also found that the method of image analysis proposed allows to detect fibres with an accuracy appropriate for the problem under consideration. The invention presented has already been registered in a Patent Office as submission no. P.411294. [ABSTRACT FROM AUTHOR]

Both phosphors and quantum dots are currently used in liquid crystal displays (LCDs), with GE's KSF narrow red phosphor demonstrating the best possible red color point, reliability, and efficiency. Next generation miniLED and microLED based displays require excellent color quality (gamut) and high brightness which will require color conversion materials with high EQE and narrow emission peaks. Here we describe recent advancements in submicron narrow‐band phosphors which are being implemented in next‐generation miniLED displays, and being considered for enabling full‐color microLED and luminescent color filter displays of the future due to their excellent optical performance and robust nature. [ABSTRACT FROM AUTHOR]

There is an ongoing need for explosive detection strategies to uncover threats to human security including illegal transport and terrorist activities. The widespread military use of the explosive trinitrotoluene (TNT) for landmines poses another particular threat to human health in the form of contamination of the surrounding environment and groundwater. The detection of explosives, particularly at low picogram levels, by using a molecular sensor is seen as an important challenge. Herein, we report on the use of a fluorescent metal-organic framework hydrogel that exhibits a higher detection capability for TNT in the gel state compared with that in the solution state. A portable sensor prepared from filter paper coated by the hydrogel was able to detect TNT at the picogram level with a detection limit of 1.82 ppt (parts per trillon). Our results present a simple and new means to provide selective detection of TNT on a surface or in aqueous solution, as afforded by the unique molecular packing through the metal-organic framework structure in the gel formation and the associated photophysical properties. Furthermore, the rheological properties of the MOF-based gel were similar to those of a typical hydrogel. [ABSTRACT FROM AUTHOR]

Europium (III) with different concentrations (0.2, 0.4 and 0.8 %)-TiO doped silica composite systems were sensitized by sol-gel method. Different spectroscopic and microscopic tools characterized the composites. The Europium ion incorporated into the liquid silica-titania solution acts as red light emission center in the luminescent materials. This luminescent nano composite pigment has great potential of application in preparing luminescent ink. Inkjet printer loaded with the prepared ink to show its potential usage as tagging material performed the printing test on a white paper. [ABSTRACT FROM AUTHOR]

The new analysis of the previously published data on the nanocrystalline CaYTiNbO7:Eu indicates an occurrence of the size-induced structural phase transition like in other nanocrystalline phosphors of pyrochlore structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zero-dimensional (0D) hybrid metal halides [(2-mb)tpp] 2 Cd 1- x Mn x Cl 4 solid solutions were synthesized by mechanochemical method. • The [(2-mb)tpp] 2 Cd 1- x Mn x Cl 4 exhibit tunable emission color through adjusting the Cd/Mn molar ratio or excitation wavelength. • The applications of [(2-mb)tpp] 2 Cd 1- x Mn x Cl 4 in multicolor imaging and anti-counterfeiting encryption are developed. • White light-emitting diodes were obtained by using [(2-mb)tpp] 2 MnCl 4 as the green phosphor. Zero-dimensional (0D) hybrid metal halides (HMHs) have received widespread concern due to their unique structures and splendid luminescent properties. However, the syntheses of HMHs primarily rely on crystal growth methods in solution or ion-thermal conditions, which are time-consuming and require extensive use of organic solvents. On the other hand, the reported HMHs usually exhibiting only one emission color hinder their further applications. Herein, we report a series of 0D HMHs solid solutions of [(2-mb)tpp] 2 Cd 1- x Mn x Cl 4 [(2-mb)tpp = (2-methylbenzyl)triphenylphosphine and x = 0–1] synthesized through a facile mechanochemical method. The emission color of [(2-mb)tpp] 2 Cd 1- x Mn x Cl 4 can be tuned from purplish-blue, bluish-green, to green light by adjusting the Cd/Mn molar ratio or excitation wavelength. Thus different luminescent panda and quick response (QR) code patterns can be designed with [(2-mb)tpp] 2 Cd 1- x Mn x Cl 4 as luminescent dyes for potential applications in multicolor imaging and anti-counterfeiting encryption. Moreover, owing to the excellent thermal stability, the as-fabricated white light emitting diode (WLED) with [(2-mb)tpp] 2 MnCl 4 as the green phosphor possesses an applicable correlated color temperature (CCT = 5305 K), an ultrahigh color rendering index (CRI, Ra = 95.4), and the CIE chromaticity coordinates of (0.3386, 0.3864) corresponding to pure white light. This work provides guidance for the rapid, facile, economical, and large-scale synthesis of HMHs with multiple luminescent centers, and exhibits the development of these materials in potential applications such as anti-counterfeiting luminescent papers and WLEDs. [ABSTRACT FROM AUTHOR]

We have demonstrated efficient speckle reduction techniques by using both micro-vibrated and mixing light methods for solid-state backlighting source applications. A micro-vibrated-reflectivephosphor paper is used for speckle suppression and white light generation. A mixing speckle contrast (SC) is defined, and the almost speckle-free results are achieved. [ABSTRACT FROM AUTHOR]

A bioassay based on DNA hybridization on cellulose paper is a promising format for gene fragment detection that may be suited for in-field and rapid diagnostic applications. We demonstrate for the first time that luminescence resonance energy transfer (LRET) associated with upconverting phosphors (UCPs) can be used to develop a paper-based DNA hybridization assay with high sensitivity, selectivity and fast response. UCPs with strong green emission were synthesized and subsequently functionalized with streptavidin (UCP-strep). UCP-strep particles were immobilized on cellulose paper, and then biotinylated single-stranded oligonucleotide probes were conjugated onto the UCPs via streptavidin–biotin linkage. The UCPs served as donors that were LRET-paired with Cy3-labeled target DNA. Selective DNA hybridization enabled the proximity required for LRET-sensitized emission from Cy3, which was used as the detection signal. Hybridization was complete within 2 min, and the limit of detection of the method was 34 fmol, which is a significant improvement in comparison to an analogous fluorescence resonance energy transfer (FRET) assay based on quantum dots. The assay exhibited excellent resistance to nonspecific adsorption of noncomplementary short/long DNA and protein. The selectivity of the assay was further evaluated by one base pair mismatched (1BPM) DNA detection, where a maximum signal ratio of 3.1:1 was achieved between fully complementary and 1BPM samples. This work represents a preliminary but significant step for the development of paper-based UCP-LRET nucleic acid hybridization assays, which offer potential for lowering the limit of detection of luminescent hybridization assays due to the negligible background signal associated with optical excitation by near-infrared (NIR) light. [ABSTRACT FROM AUTHOR]

Perovskite quantum dots (PQDs) are a competitive candidate for next‐generation display technologies as a result of their superior photoluminescence, narrow emission, high quantum yield, and color tunability. However, due to poor thermal resistance and instability under high energy radiation, most PQD‐based white light‐emitting diodes (LEDs) show only modest luminous efficiency of ≈50 lm W−1 and a short lifetime of <100 h. In this study, by incorporating cellulose nanocrystals, a new type of QD film is fabricated: CH3NH3PbBr3 PQD paper that features 91% optical absorption, intense green light emission (518 nm), and excellent stability attributed to the complexation effect between the nanocellulose and PQDs. The PQD paper is combined with red K2SiF6:Mn4+ phosphor and blue GaN LED chips to fabricate a high‐performance white LED demonstrating ultrahigh luminous efficiency (124 lm W−1), wide color gamut (123% of National Television System Committee), and long operation lifetime (240 h), which paves the way for advanced lighting technology. [ABSTRACT FROM AUTHOR]

A paper-based microfluidic device with upconversion fluorescence assay (named as UC-μPAD) is proposed The device is fabricated on a normal office printing sheet with a simple plotting method. Upconversion phosphors (UCPs) tagged with specific probes are spotted to the test zones on the μPAD, followed by the introduction of assay targets. Upconversion fluorescence measurements are directly conducted on the test zones after the completion of the probe-to-target reactions, without any post-treatments. The UC-μPAD features very easy fabrication and operation, simple and fast detection, low cost, and high sensitivity. UC-μPAD is a promising prospect for a clinical point-of-care test. [ABSTRACT FROM AUTHOR]

A color conversion film with green and red color conversion materials is needed for mini‐LED based LCD displays because the traditional approach of using phosphors on‐chip does not work for such displays due to technical limitations. Either narrow band phosphors (like B‐Sialon or KSF) or quantum dots (like CdSe or InP) are commercially used in color conversion films and the selection of these materials is mainly driven by display performance including picture quality but also battery‐life. We present and discuss the pros and cons of the different material combinations in relation to the specific display types of TV, monitors, notebooks and tablets and will show where perovskite quantum dots will make a difference. Furthermore we give an update on the development and commercialization status for our color conversion films which are based on green perovskite QDs and different red emitter materials. [ABSTRACT FROM AUTHOR]

Both phosphors and quantum dots are currently used in liquid crystal displays (LCDs), with GE's KSF narrow red phosphor demonstrating the best possible red color point, reliability, and efficiency. Next generation miniLED and microLED based displays require excellent color quality (gamut) and high brightness which will require color conversion materials with high EQE and narrow emission peaks. Here we describe recent advancements in narrow‐band phosphors which are being implemented in next‐generation miniLED displays, and being considered for enabling full‐color microLED displays of the future due to their excellent optical performance and robust nature. [ABSTRACT FROM AUTHOR]

Green and narrow‐band photoluminescence at 535 nm with 30 nm of FWHM was recently achieved by Zn(Te,Se) alloy QDs, and the potential of Zn(Te,S) alloy QDs as a red phosphor was theoretically demonstrated. In this paper, the recent progress in cadmium‐free QD is reviewed focusing on ZnTe‐based alloy QDs. [ABSTRACT FROM AUTHOR]

With funnel‐tube array, the optical efficiency of the color‐converted micro‐LED display is improved by ~3X, while the crosstalk is eliminated. After optimization of the taper angle, the ambient contrast ratio is also improved due to higher light intensity. [ABSTRACT FROM AUTHOR]

Both phosphors and quantum dots are currently used in liquid crystal displays (LCDs), with GE's KSF narrow red phosphor demonstrating the best possible red color point, reliability, and efficiency. Next generation miniLED and microLED based displays require excellent color quality (gamut) and high brightness which will require color conversion materials with high EQE and narrow emission peaks. Here we describe recent advancements in narrow‐band phosphors which are being implemented in next‐generation miniLED displays, and being considered for enabling full‐color microLED displays of thefuture due to their excellent optical performance and robust nature. [ABSTRACT FROM AUTHOR]

Abstract: Cerium-doped yttrium aluminum garnet phosphors with laminar structure were synthesized by a very simple method using filter paper as the structure template at 1100°C. Three thin plate samples with different morphology were prepared via the different preparation procedures. The crystalline phase, composition, surface morphology and luminescence property of the synthesized samples are investigated by X-ray diffraction, energy dispersive X-ray analysis, scanning electron microscopy, and photoluminescence spectrum. Results indicate that the metal cations are combined with the filter paper templates and are self-assembled on the surface of filter paper. The self-assembly induced the growth of YAG: Ce crystal and the formation of the plate-like YAG: Ce samples. These plate-like bulky grains are composed of YAG: Ce nanoparticles (about 30nm), and they show yellow–green fluorescent emissions. The YAG: Ce with laminar structure facilitates the increase of PL intensity. [Copyright &y& Elsevier]

Hydrogen sulfide is present in active or extinct volcanic areas (mofettas). The habitable premises in these areas are affected by the presence of hydrogen sulfide, which, even in low concentrations, gives off a bad to unbearable smell. If the living spaces considered are closed enclosures, then a system can be designed to reduce the concentration of hydrogen sulfide. This paper presents a membrane-based way to reduce the hydrogen sulfide concentration to acceptable limits using a cellulosic derivative–propylene hollow fiber-based composite membrane module. The cellulosic derivatives considered were: carboxymethyl–cellulose (NaCMC), P1; cellulose acetate (CA), P2; methyl 2–hydroxyethyl–cellulose (MHEC), P3; and hydroxyethyl–cellulose (HEC), P4. In the permeation module, hydrogen sulfide is captured with a solution of cadmium that forms cadmium sulfide, usable as a luminescent substance. The composite membranes were characterized by SEM, EDAX, FTIR, FTIR 2D maps, thermal analysis (TG and DSC), and from the perspective of hydrogen sulfide air removal performance. To determine the process performances, the variables were as follows: the nature of the cellulosic derivative–polypropylene hollow fiber composite membrane, the concentration of hydrogen sulfide in the polluted air, the flow rate of polluted air, and the pH of the cadmium nitrate solution. The pertraction efficiency was highest for the sodium carboxymethyl–cellulose (NaCMC)–polypropylene hollow fiber membrane, with a hydrogen sulfide concentration in the polluted air of 20 ppm, a polluted air flow rate (QH2S) of 50 L/min, and a pH of 2 and 4. The hydrogen sulfide flux rates, for membrane P1, fall between 0.25 × 10−7 mol·m2·s−1 for the values of QH2S = 150 L/min, CH2S = 20 ppm, and pH = 2 and 0.67 × 10−7 mol·m−2·s−1 for the values of QH2S = 50 L/min, CH2S = 60 ppm, and pH = 2. The paper proposes a simple air purification system containing hydrogen sulfide, using a module with composite cellulosic derivative–polypropylene hollow fiber membranes. [ABSTRACT FROM AUTHOR]

Persistent luminescence phosphors have attracted much attention in the realm of anti-counterfeiting and information storage because of their characteristic properties of optical information storage, long persistent luminescence, and simplicity of design. At present, traditional anti-counterfeiting persistent luminescence phosphors are based on single-colour luminescence and generally have poorly secure anti-counterfeiting capabilities. In this work, Ca1−1/2xCd1−1/2xGe7O16:xSm3+ (x = 0, 0.0025, 0.005, 0.01, 0.015, 0.02, and 0.025) phosphors were synthesized using a high-temperature solid-state reaction method, which demonstrated potential as multi-colour and two-mode anti-counterfeiting persistent luminescence materials. With an increase in doping concentration of Sm3+ ions in the host, the materials could emit blue-to-pink photoluminescence under 254 nm UV lamp illumination. After excitation under a 254 nm UV lamp, the materials showed persistent luminescence performance with a pink persistent luminescence colour, and the duration could exceed 4 h. The persistent luminescence mechanism and electron traps inside the samples were analyzed by plotting their thermoluminescence curves after excitation cessation. The results show that at least two types of traps existed in the Ca1−1/2xCd1−1/2xGe7O16:0.01Sm3+ phosphor. The phosphors were used to synthesize anti-counterfeiting ink, which was then used to make an optical anti-counterfeiting pattern through screen printing. The pattern could barely be observed on white paper in sunlight but was visible in different colours under an irradiation of 254 nm and in a low light environment. The results show that the produced phosphors have a high level of application potential for use in enhanced optical anti-counterfeiting applications. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) organic light emitting diodes (OLED has evolved to become the futuristic lighting technology due to its enormous potentials ranging from security identification and therapeutics. In this presentation, we elaborate the design and preparation of a series of Pt(II) based emitters, to which the exceedingly strong intermolecular Pt⋅⋅⋅Pt interaction fostered the metal‐metal‐to‐ligand charge transfer transition characteristics upon excitation in thin films and, thereby, gave efficient electroluminescence with peak wavelength around 800 nm and beyond. Consequently, NIR OLEDs based on these Pt(II) complexes were fabricated using direct vacuum deposition in forming the nondoped emissive layer. Moreover, the relevant device efficiencies are significantly better than all NIR OLEDs ever documented in literature. [ABSTRACT FROM AUTHOR]

Perovskite quantum dots films (PQDF) are emerging as low‐cost alternatives to improve the color gamut of liquid crystal display (LCD) backlights due to their narrow half peak width. In this paper, hybrid composite films with green perovskite quantum dots (PQDs) and red rare earth phosphors were combined in a dual layer film for LCD backlight display applications. By combining the in‐situ fabricated green emissive PQDF with KSF phosphor or red nitride phosphor (NP), we prepared hybrid composite films of green PQDF and red phosphors with high brightness and wide color gamut. The color gamut of PQDs‐KSF is 83.1% of Rec. 2020 due to the narrow full‐width‐at‐half‐maximum of PQDs and KSF phosphors. These composite films have great potential in the application of LCD backlights. [ABSTRACT FROM AUTHOR]

Red phosphors play an important role in improving the light quality and color rendering index of white light-emitting diodes (WLEDs) for lighting. In this paper, we report the transition ion Mn4+-activated deep red phosphor GdGeSbO6:x%Mn4+ and analyze its crystal structure, composition and luminescence behavior in detail. Its optimal doping concentration of Mn4+ is 0.3%. Under ultraviolet (UV) excitation, GdGeSbO6:0.3%Mn4+ produces a narrow emission peak centred at 682 nm in the range of 650–800 nm with a full width at half maximum (FWHM) of 25 nm, which is attributed to the spin-prohibited 2Eg → 4A2g transition of Mn4+ ions. Notably, the optimal phosphor GdGeSbO6:0.3%Mn4+ has a high internal quantum efficiency (IQE ≈ 65%) and excellent thermal stability performance (I423 K/I303 K ≈ 62%). The synthesis of high-performance warm WLEDs and full-spectrum WLEDs was achieved by combining and coating GdGeSbO6:0.3%Mn4+ phosphors with commercial phosphors on the surface of a 365 nm UV chip. [ABSTRACT FROM AUTHOR]

Chromium is a common heavy metal element that is harmful to the ecosystem as well as human health, so sensitive detection of chromium ions in solution is important for life and health. In this paper, a series of Eu3+-doped KBi3F10 fluorescent powders were successfully synthesized by a one-step solvothermal method for the selective detection of Cr3+, CrO42− and Cr2O72− ions in an aqueous solution. When adjusting the pH value to 3 and adding PVP as an additive, the obtained KBi3F10:12%Eu3+ phosphor showed excellent red luminescence. Due to the competitive absorption and the inner filter effect of Cr3+, CrO42− and Cr2O72− ions, the red emission from Eu3+ ions produces fluorescence quenching, which can be used to detect them with good selectivity. And the detection limits are as low as 0.19 μM, 0.38 μM and 0.094 μM for Cr3+, CrO42− and Cr2O72− ions, respectively. Other metal ions and common anions showed little interference with chromium ion detection. The obtained fluorescent probe has good recyclability, accurate and reliable detection results, simple operation and low cost and is easy to promote, which make it an excellent three-in-one probe for chromium detection. [ABSTRACT FROM AUTHOR]

In this paper, a three-wavelength exciting and temperature-sensing Gd1.559Y0.03Lu0.02Er0.13Yb0.26Ho0.001O2S phosphor excited by 980 nm, 1064 nm and 1550 nm was prepared for the first time by a coprecipitationhigh temperature solid-state reaction (HSR). Three different up-conversion changes were observed with an increase in temperature under 980 nm, 1064 nm and 1550 nm laser excitation. The fluorescence intensity ratio (FIR) equations of the sample excited by 980 nm, 1064 nm and 1550 nm were obtained at 313-553 K. The three kinds of absolute sensitivity were 0.0016 (479 K), 0.0096 (553 K) and 0.1528 (553 K). The upconversion process excited by 980 nm, 1064 nm and 1550 nm laser radiation was analyzed and the causes of the three different changes are explained. The stability of the Gd1.559Y0.03Lu0.02Er0.13Yb0.26Ho0.001O2S phosphor as a temperature sensor was tested by a cyclic test. It is proved that the Gd1.559Y0.03Lu0.02Er0.13- Yb0.26Ho0.001O2S phosphor is a novel and valuable up-conversion optical temperature sensor. [ABSTRACT FROM AUTHOR]

The first generation of digital-cinema projectors has now been deployed into the majority of movie theaters around the world. The illumination technology used for that first generation was xenon lamps. When that choice was made xenon was the only viable technology that could achieve digital cinema's goals. Today, cinema has a new set of challenges and a new set of technologies to choose from. Now that laser and laser-phosphor are mainstream illumination technologies cinema-projection engineers have an entirely new set of design decisions to make. [ABSTRACT FROM AUTHOR]

A highly efficient phosphor with exceptional luminescence properties is crucial for achieving high-quality solid-state white-light illumination. Here, this paper presents a groundbreaking discovery, an innovative blue–violet emitting Ba1.31Sr3.69(BO3)3Cl:Ce3+ (BSBCl:Ce3+) phosphor designed with remarkable thermal stability and quantum efficiency for full spectrum white light-emitting diodes (WLEDs). By employing a high-temperature solid-phase method, we synthesized various BSBCl:xCe3+ phosphors with different Ce3+ doping concentrations. Remarkably, BSBCl:0.03Ce3+ displays a broad excitation band from 250 nm to 400 nm, rendering it compatible with commercial near-ultraviolet (UV) LED chips. Under 330 nm excitation, this phosphor emits blue light with an astonishing 88.2% internal quantum efficiency (IQE) and an impressive 60.9% external quantum efficiency (EQE). Notably, when employed in the temperature range of 298–473 K, the synthesized BSBCl:0.03Ce3+ phosphor exhibits exceptional color stability and thermal stability (I423 K/I298 K = 83%). Utilizing BSBCl:0.03Ce3+ as the blue–violet emitting component in the fabrication of WLED devices has demonstrated significant advancements in the color rendering index. These findings underscore the potential of BSBCl:Ce3+ phosphors for a wide range of applications in health-oriented indoor illumination. [ABSTRACT FROM AUTHOR]

An excellent hybrid III‐nitride/nanocrystal nanohole light‐emitting diode (h‐LED) has been developed utilizing förster nonradiative resonant energy transfer (NRET) between violet/blue emitting InGaN/GaN multiple quantum wells (MQWs) and various wavelength emitting nanocrystals (NCs) as color conversion mediums. InGaN/GaN MQWs are fabricated into nanoholes by soft nanoimprint lithography to minimize the separation between MQWs and NCs. A significant reduction in the decay lifetime of excitons in the MQWs of the hybrid structure has been observed as a result of the NRET from the nitride emitter to NCs. The NRET efficiency of the hybrid structures is obtained from the decay curves, as high as 80%. Based on a systemic optimization for white emission indexes, a series of hybrid ternary complementary color h‐LEDs have been demonstrated with a high color rendering index, up to 82, covering the white light emission at different correlated color temperatures ranging from 2629 to 6636 K, corresponding to warm white, natural white, and cold white. The efficiency droop of hybrid LEDs was validly suppressed, which mainly resulted from the extraction of excess carrier concentrations in InGaN/GaN MQWs via the rapid non‐radiative resonant energy transfer process under the higher injection condition, revealing a great potential to realize efficient white light emitters in the future. [ABSTRACT FROM AUTHOR]

Efficient white LEDs with efficacy of > 200 lm/W are much desirable for lighting and displays. LCDs is the market leader with an approximate 70% market share, particularly in the medium‐ to large‐size display segment. The largest portion of power consumption for LCDs belongs to LCD backlight, accounting for 70%–80% of the total power consumption, which strongly depends on the content and resolution of display panels. [1–8] The polarizer and color filters are the two main components responsible for high‐power consumption. Although the phosphor‐based LED backlights are much more efficient than the CCFL backlight, the efficiency of display backlight LEDs varies in the range of 70–85 lm/W. A large portion of the phosphor‐based LED light is lost in color filters [1–5]. The LED efficacy further decreases at the high brightness required for outdoor applications [4]. Intensive efforts have been made to replace the phosphor with quantum dots‐based downconverters, but the efficiency and stability of these devices are still in their infancy. Quantum rods (QRs), the elongated shape nanoparticles, show superior properties such as relatively larger Stokes shifts, polarized emission, and high light out‐coupling efficiency in the solid‐state. The challenges are as follows: 1. high quantum yield of QRs in the thin solid films covering the whole visible range; 2. good in‐plane alignment of the QRs on the LEDs; and 3. high photo‐stability and low‐temperature quenching. In this talk, we will try to discuss all these challenges. We will also discuss the merits of gradient alloyed CdSe/ZnXCd1‐XS/ZnS and CdSe/CdS/ZnS core/shell/shell QRs downconverters showing high efficacy LEDs covering a wide color gamut. These QRs‐based LEDs attain the luminous efficacy (LE) of 149 lm/W (@10mA), wide color gamut (118% NTSC), which is exceedingly higher than the state‐of‐the‐art quantum dot and phosphor‐based on‐chip LED, which paves the way for the future display backlight with the efficacy of > 200 lm/W. [ABSTRACT FROM AUTHOR]

Blue/deep-blue emission is crucial for organic optoelectronics but remains a formidable challenge in organic afterglow due to the difficulties in populating and stabilizing the high-energy triplet excited states. Here, a facile strategy to realize the efficient deep-blue organic afterglow is proposed via host molecules to sensitize the triplet exciton population of guest and water implement to suppress the non-radiative decays by matrices rigidification. A series of highly luminescent deep-blue (405–428 nm) organic afterglow materials with lifetimes up to 1.67 s and quantum yields of 46.1% are developed. With these high-performance water-responsive materials, lifetime-encrypted rewritable paper has been constructed for water-jet printing of high-resolution anti-counterfeiting patterns that can retain for a long time (>1 month) and be erased by dimethyl sulfoxide vapor in 15 min with high reversibility for many write/erase cycles. These results provide a foundation for the design of high-efficient blue/deep-blue organic afterglow and stimuli-responsive materials with remarkable applications. Though realizing organic materials with deep blue emission is attractive for next-generation display technologies, achieving this emission in afterglow molecules remains a challenge. Here, the authors report blue organic afterglow via a strategy involving guest sensitization and matrix rigidification. [ABSTRACT FROM AUTHOR]

A thin film of quantum dots (QD) was used to visualize the local photo-response of polycrystalline CdTe solar cells by down-converting an electron beam of high energy to photons of visible light. The efficient photon generation in the QD film is compared to cathodoluminescence of the high-purity bulk semiconductors and phosphor. [ABSTRACT FROM AUTHOR]

Optimization of angular light distribution in organic layer and light extraction structure based on high refractive index substrate were investigated. Due to advanced optical design for decreasing waveguide and evanescent modes, white OLED device with outstandingly high efficacy of 133 lm/W at 1,000 cd/m2 was realized. [ABSTRACT FROM AUTHOR]

The micro-prism film on the incident surface of the remote phosphor film extracts backward light through a double reflection and the micro-prism film on the exit surface retains blue light inside the remote phosphor film to enhance phosphor excitation. Yu et al. [[6]] proposed micro-prism patterned remote phosphor films, made by large-scale roll-to-roll imprinting, to significantly improve the light and color performance of LEDs. Half of the published papers focus on light-emitting diode (LED) microsystems and related microelectronic systems [[4], [6], [8]], three papers discuss the cooling techniques of electronic microsystems [[10], [12]], and the final three papers present several mechanical microsystems [[13], [15]]. We [[5]] developed a phosphor converter based on a micro-angle tunable tilted filter for hybrid-type laser lighting devices to address the issue of carbonizing under high-energy density in silicone phosphor converters. [Extracted from the article]