Absorption Of Blue Light Research Articles

Rod-shaped LuAG:Ce transparent ceramic enabling ultrahigh forward efficiency for laser lighting in a transmissive mode.

Ceramic phosphors have high thermal conductivity and high thermal stability, showing great potential for use in laser lighting. However, it is difficult to further improve the forward efficiency in transmissive mode because of the arbitrarily emitting ceramic phosphors and light loss by secondary optical components. Here, an effective design of rod-shaped LuAG:Ce transparent ceramics was proposed, and the silicone encapsulated ceramic-based devices could operate stably under 3.5 W laser excitation, possessing a luminous efficiency of 150-180 lm/W, far exceeding the level of existing commercial transmissive mode. Besides, because of the gradual absorption of blue light and the gradient distribution of heat, the rod-shaped LuAG:Ce transparent ceramics could bear a power density of 46 W/mm2 without luminous saturation, and the thermal-induced luminous degradation only accounted for 7% under a 15 min operation. The ceramic-based laser lighting sources with low divergence angle (∼4°) and uniform spatial distribution were obtained. Our optimized transparent ceramic rod and encapsulation scheme provided a solution to improve the efficiency of a transmissive mode for laser lighting.

Photodriven Ammonia Synthesis from Manganese Nitrides: Photophysics and Mechanistic Investigations.

Ammonia synthesis from N,N,O,O-supported manganese(V) nitrides and 9,10-dihydroacridine using proton-coupled electron transfer and visible light irradiation in the absence of precious metal photocatalysts is described. While the reactivity of the nitride correlated with increased absorption of blue light, excited-state lifetimes determined by transient absorption were on the order of picoseconds. This eliminated excited-state manganese nitrides as responsible for bimolecular N-H bond formation. Spectroscopic measurements on the hydrogen source, dihydroacridine, demonstrated that photooxidation of 9,10-dihydroacridine was necessary for productive ammonia synthesis. Transient absorption and pulse radiolysis data for dihydroacridine provided evidence for the presence of intermediates with weak E-H bonds, including the dihydroacridinium radical cation and both isomers of the monohydroacridine radical, but notably these intermediates were unreactive toward hydrogen atom transfer and net N-H bond formation. Additional optimization of the reaction conditions using higher photon flux resulted in higher rates of the ammonia production from the manganese(V) nitrides due to increased activation of the dihydroacridine.

Construction of In2S3–In(OH)3–ZnS nanofibers for boosting photocatalytic hydrogen evolution

This research involved synthesizing In2S3–In(OH)3 nanosheets through a simple hydrothermal method at a low reaction temperature. The impact of different indium chloride concentrations on the morphology and crystal structure of In2S3–In(OH)3 nanostructures was investigated. The discussion extended to the photocatalytic hydrogen evolution of both In2S3–In(OH)3 nanosheets and nanofibers. These findings indicated that In2S3–In(OH)3 nanofibers exhibited optimal photocatalytic hydrogen production at various indium chloride concentrations. Furthermore, In2S3–In(OH)3–ZnS heterostructures were created by reacting In2S3–In(OH)3 nanosheets with varying concentrations of ZnS precursors. The study delved into the morphology and crystal structure, emphasizing photocatalytic hydrogen production in In2S3–In(OH)3–ZnS nanofibers under different concentrations of ZnS precursors. Remarkably, the In2S3–In(OH)3–ZnS nanofibers demonstrated exceptional hydrogen production efficiency, attributed to their larger specific surface area, improved blue light absorption, and reduced electron-hole pair recombination. Additionally, a comprehensive analysis explored the photocatalytic reaction mechanism, pH values, sacrificial reagents, sacrificial reagent concentrations, light source types, and intensities. These results highlighted the exceptional reusability of In2S3–In(OH)3–ZnS nanofibers in photocatalytic hydrogen production, showcasing their potential for cost-effective and highly efficient applications in diverse fields.

Bilberry Extract in Macular Pigment Density Improvement

Macular Pigments (MPs), by absorbing potentially toxic short-wavelength (400–500 nm) visible light, provide protection against photo-chemical damage. A new method of MPs levels screening analyzes polarization-dependent absorption of blue light by MPs, which results in the entoptic phenomenon called Haidinger’s Brushes (HB). Subjects identify the direction of rotation of HB when presented with a circular stimulus illuminated with an even intensity of polarized white light in which the electric field vector was rotating either clockwise or anti-clockwise. The examination was performed at baseline and after 3 months of daily intake of 320 mg bilberry extract, from Vaccinium myrtillus L. and standardized to contain more than 36% of anthocyanins (anthocyanosides), in normal subjects and MPs improvement was recorded after 3 months of dietary supplements. The results suggest a challenging role of daily intake of 320 mg bilberry extract in macular pigment density improvement possibly due to a macular protection from oxidative damage by bilberry.

Strategically Developed Strong Red‐Emitting Oxyfluoride Nanophosphors for Next‐Generation Lighting Applications

AbstractRed‐emitting nanophosphors have a multirole in improvising the next‐generation bulk/micro/nano‐level lighting devices, particularly in refining white light quality and device performance. Nonetheless, it is difficult to synthesize nanosized phosphors with good yield and paralleled high absorption efficiency both in UV and blue regions, which is critical for modern lighting. Herein, new Mg14Ge4.99+σO24‐x+δFx: Mn4+ red nanoparticles with sizes below 100 nm are designed to improve not only the luminescence but also the blue light absorption. This approach has validated the applicability of red‐emitting nanophosphors into flexible UV and blue nitride nanowire light‐emitting‐diodes (LEDs), and commercial bulk LEDs, for the first time, with boosted intensity and color superiority for a variety of lighting utilizations. For these phosphor LEDs (pc‐LEDs), optimized red nanophosphor with an external quantum efficiency of ≈44.5%, color purity of ≈100%, and thermal stability of ≈72% at 150 °C is used. The optimized nanophosphor is combined with a flexible UV‐AlGaN/GaN nanowire LED and a blue‐InGaN/GaN‐LED. The resultant devices show promising red electroluminescence without any degradation at elevated currents. Finally, several unfamiliar LED packaging is designed with yellow and red phosphors implemented on 2 sets of double LED units to reach CRI > 85. The re‐premeditated LED packages are useful for high‐definition lighting.

Stable colour conversion layer with enhanced conversion efficiency by incorporating nanoparticles for micro-LED display application

Due to their promising optical performance, micro-light emitting diodes (micro-LEDs) based on colour conversion layer (CCL) have garnered significant attention as the next-generation display technology. However, fabricating CCL with excellent conversion efficiency (CE) with minimal blue light leakage for miniaturized sub-pixel designing is still in its infancy. Herein, we have demonstrated CCL of a thickness (<3.5 μm) based on an organic-inorganic hybrid system incorporated with Titanium dioxide (TiO2) and Zinc Oxide (ZnO) Nanoparticles (NPs) with high CE. The inclusion of the NPs enhances the absorption of blue light within the CCL. We further combined the CCL with a colour purification filter to mitigate blue light leakage, which recycles blue light and suppresses blue light loss, resulting in improved CE. Specifically, we achieved a CE of 83.80 % for the green CCL and 66.97 % for the red CCL. Subsequently, full-colour arrays with a pixel size of 4 μm × 4 μm were successfully patterned and fabricated based on reduced thickness and improved optical performance using NP-doped CCL. This paves the way for cost-effective higher-resolution micro-LED displays for various applications.

Microwave‐Assisted Confining Growth and Liquid Exfoliation of sp3‐Hybrid Carbon Nitride Nano/Micro‐Crystals

As one promising carbon‐based material, sp3‐hybrid carbon nitride has been predicted with various novel physicochemical properties. However, the synthesis of sp3‐hybrid carbon nitride is still limited by the nanaoscale, low crystallinity, complex source, and expensive instruments. Herein, we have presented a facile approach to the sp3‐hybrid carbon nitride nano/micro‐crystals with microwave‐assisted confining growth and liquid exfoliation. Actually, the carbon nitride nano/micro‐crystals can spontaneously emerge and grow in the microwave‐assisted polymerization of citric acid and urea, and the liquid exfoliation can break the bulk disorder polymer to retrieve the highly crystalline carbon nitride nano/micro‐crystals. The obtained carbon nitride nano/micro‐crystals present superior blue light absorption strength and surprising photoluminescence quantum yields of 57.96% in ethanol and 18.05% in solid state. The experimental characterizations and density functional theory calculations reveal that the interface‐trapped localized exciton may contribute to the excellent intrinsic light emission capability of carbon nitride nano/micro‐crystals and the interparticle staggered stacking will prevent the aggregation‐caused‐quenching partially. Finally, the carbon nitride nano/micro‐crystals are demonstrated to be potentially useful as the phosphor medium in light‐emitting‐diode for interrupting blue light‐induced eye damage. This work paves new light on the synthesis strategy of sp3‐hybrid carbon nitride materials and thus may push forward the development of multiple carbon nitride research.

Organo‐Soluble Colloidal MoS2 Quantum Dots (QDs) as an Efficient Photocatalyst for α‐Amino Phosphonate Synthesis

Abstractα‐Amino phosphonates are bio‐isosteres of amino acids and have numerous biochemical activities. While they are generally prepared via carbon–phosphorus bond formation using a plethora of methods but using recyclable photo‐catalysts and readily accessible amine and phosphites are not commonly used in synthesis. Herein, we used organo‐soluble MoS2 Quantum Dots (QDs) as an exceptionally efficient nano‐photocatalyst for the synthesis of α‐amino phosphonates. Our approach emphasizes on photocatalysis within organic media, providing a facile and effective method for conducting these intricate organic conversions under mild conditions. This straightforward process harnesses the power of molecular oxygen (O2) as an oxidizing agent. To elaborate, our method is intricately guided by the inherent capability of MoS2 QDs to enter an excited state upon absorption of blue light. This excited state bears appropriate potential energy to initiate the formation of reactive iminium ion species from N‐phenyl benzylamine, thus driving the desired product formation. Mechanistic analysis has also unveiled the pivotal role of MoS2 QDs in generating reactive superoxide radicals from O2 through single electron transfer (SET), underscoring their significance in the process. Remarkably, this photocatalytic transformation furnishes a diverse array of functionalized products, expanding its applicability and potential implications in various contexts.

Local Light Field Control Enables Efficient Quantum Dot Color Conversion Films for Mini‐LED Backlit Displays

AbstractQuantum dot (QD) color conversion films (QD‐CCFs) are used in ultrahigh definition (UHD) Mini‐LED backlit displays due to their narrow band emission and high color purity. However, their poor light conversion efficiency (LCE) leads to greater film thickness and thus high cost. Herein, this study proposes a local light field control strategy to enhance the LCE of QD‐CCFs using high‐refractive BN nanosheets. The LCEs of the green and red QD‐CCFs can increase from 29.9% and 34.8% to 67.4% and 91.0% after adding BN nanosheets, respectively. Combining the experimental data with the finite‐difference time domain (FDTD) simulations, the enhanced LCEs can be attributed to observably increased blue light absorption and improved light extraction efficiency of the light emitted from QDs. The white Mini‐LEDs, prepared by integrating the optimized QD‐CCFs containing BN nanosheets with blue Mini‐LED chips, show a high luminous efficiency of 70.2 lm W−1, a high external quantum efficiency of 36.2%, and a wide color gamut of 96.3% Rec. 2020 standards. This work provides an interesting idea for designing high‐efficiency QD‐CCFs toward low‐cost UHD Mini‐LED backlit displays.

The Influence of the Alkylamino Group on the Solvatochromic Behavior of 5-(4-substituted-arylidene)-1,3-dimethylpyrimidine-2,4,6-triones: Synthesis, Spectroscopic and Computational Studies.

Advances in electronics and medical diagnostics have made organic dyes extremely popular as key functional materials. From a practical viewpoint, it is necessary to assess the spectroscopic and physicochemical properties of newly designed dyes. In this context, the condensation of 1,3-dimethylbarbituric acid with electron-rich alkylaminobenzaldehyde derivatives has been described, resulting in a series of merocyanine-type dyes. These dyes exhibit intense blue-light absorption but weak fluorescence. An electron-donating alkylamino group at position C4 is responsible for the solvatochromic behavior of the dyes since the lone electron pair of the nitrogen atom is variably delocalized toward the barbituric ring, which exhibits electron-withdrawing properties. This was elucidated, taking into account the different geometry of the amino group. The intramolecular charge transfer in the molecules is responsible for the relatively high redshift in absorption and fluorescence spectra. Additionally, an increase in solvent polarity moves the absorption and fluorescence to lower energy regions. The observed solvatochromism is discussed in terms of the four-parameter Catalán solvent polarity scale. The differences in the behavior of the dyes were quantified with the aid of time-dependent density functional theory calculations. The obtained results made it possible to find regularities linking the basic spectroscopic properties of the compounds with their chemical structure. This is important in the targeted search for new, practically important dyes.

Fabrication of Al2O3– Ce:(Y, Tb)3 (Al, Mn)5O12 composite ceramic phosphors for high color rendering white LED/LD illumination

Ce: YAG- Al2O3 composite ceramics are regarded as highly promising materials for laser illumination application due to their high luminous efficacy and thermal stability. Nevertheless, the Ce: YAG ceramics exhibit limited color rendering index (CRI) for indoor lighting due to their low red emission component. In this study, we synthesized high-performance Ce, Mn-doped (Y, Tb)3Al5O12–Al2O3 composite ceramic phosphors via a vacuum solid-state sintering method. It was observed that the introduction of Mn2+ ions created a second luminescence center with an emission peak centered at 580 nm. As the Mn2+ concentration increased, the emission peak redshifted from 580 nm to 591 nm, leading to a significant enhancement in the color rendering index of the ceramics. The cross-energy transfer between Tb3+ and Mn2+, Ce3+ ions augmented the absorption and conversion of blue light by the ceramics, thereby reducing the correlated color temperature greatly. Based on these findings, ceramics with a Ce3+ concentration of 3 at% and a Mn2+ concentration of 4 at% exhibited the highest CRI values (81.3 and 75.6) under both laser excitation and LED excitation, establishing them as strong candidates for achieving high color rendering in white LED/LD illumination applications.

Difluoro Dipyridomethene Boron Complexes: Synthesis, Characterization, and Ab Initio Calculations.

Molecular engineering studies on the meso-cyano difluoro dipyridomethene boron complexes are presented and two series (a and b) of novel fluorophores are extensively studied. Halogenated derivatives were reacted under Suzuki-Miyaura or Sonogashira cross coupling reactions to introduce electron-donating or electron-withdrawing functional groups on positions 1 and 2 of the aromatic ligand. All derivatives were obtained in 14-90% yields and studied in detail by structural, photophysical, and computational analyses. Both series display excellent emissive properties in solution with blue to orange fluorescence emission upon blue light absorption and promising features as solid emitters. All the spectroscopic measurements are supported and confirmed by first-principles theoretical calculations combining TD-DFT and CC2. Series b, featuring an aryl substituent onto position 1 of the aromatic core, showed significantly large Stokes shifts values.

Achieving neutral-tinted and energy-efficient electrochromic device enabled by sputtered tungsten-niobium-oxygen film for smart windows

WO3 based electrochromic device (ECD) is becoming the mostly-used one for smart windows, however, in WO3 tinted state, the intrinsically deep blue and strong infrared (IR) light absorption, resulting in a habitant discomfortableness and also an enhanced thermal gain from the heated device surface, severely restrict its diversified applications. Herein, we firstly conduct a kind of columnarly-grown and amorphous WO3 film with high concentration of niobium doping (Nb/(Nb+W) = 54.1 at.%). This film is fabricated via sputtering a home-made ceramic target, and subsequently improved by a rapid thermal annealing (RTA) process. Comparing with the conventional WO3, the newly-established system owns not only basic EC properties comprising large light modulation range, fast response, and long-term electrochemically cyclic stability, but also a neutral-tinted color (a* = −1.5, b* = 1.0) as well as a relatively lower IR absorption (63.7 %) in tinted state. These outstanding performances enable the assembled ECD with neutral color (a* = 0.6, b* = −2.7) and a higher energy efficiency in cutting down the interior space air temperature about 4.3 °C in its fully-tinted state, underscoring the potential of the tungsten-niobium-oxygen for commercially viable ECDs.

Cooperative cationic substitution strategy triggers high blue-light absorptance and near-infrared emission with high quantum efficiency in Cr3+-activated pyroxene-type assembly

Near-infrared phosphor-converted light-emitting diodes (NIR pc-LEDs) assembled with the broadband NIR-emitting phosphors has been a promising light source for application in agricultural plant lighting, night vision, food analysis and medical diagnosis. But it suffers from a low photoelectric efficiency (<30 %) due to deficiency of phosphors with high internal quantum efficiency (IQE) and strong absorption capacity in the blue spectral region. Herein, a broadband NIR-emitting luminescent material capable of efficient blue to NIR light conversion with still high IQE was developed via the chemical-composition engineering of CaMgGe2O6:Cr3+ using cooperative cationic substitution of Ca2+-Mg2+ by Na + -Ga3+. The emission profiles evolved a red-shift from 839 to 859 nm with the full width at half-maximum (FWHM) extending from 161 nm to 177 nm as the increase of [Na+-Ga3+] pairs. In addition, the IQE can be finely adjusted. Importantly, the blue-light absorption efficiency can be greatly improved to 34.8 % upon pumping by the constant excitation energy. The increased local structural distortion induced by introducing [Na+-Ga3+] pairs has been verified for the main factor causing these desirable optical properties change. Benefiting from the improvement of blue-light absorptance, the fabricated NIR pc-LED device via coating the developed phosphor on a blue LED chip achieved the larger photoelectric efficiency 31.2 %@10 mA compared to the previously reported value of 27.2 %@10 mA. The excellent performance of biomedical imaging and night vision surveillance represented by the assembled NIR pc-LED was demonstrated.

Organic hybrid tetranuclear clusteroluminogens: Blue-light-excitable LED with ultrahigh luminous efficacy

The development of highly emissive luminescent materials is vital for future light-emitting diodes, display, and scintillation applications. A series of novel organic hybrid metal halide clusters are presented here, that is, non-emission (C4H12N2)3(NH4)4Cd4Cl18 (namely, 1), pink-emission (C4H12N2)3(NH4)4Mn4Cl18 (namely, 2) and 1–2 alloy (namely, Mn-1). The crystal structure of alloy compound provides a clear insight into the Mn(II) effect. Mn(II) alloying in the host lattice successfully induces large octahedral distortion, hybrid of d/p orbitals and lower local symmetry resulting in a breaking d-d forbidden transition. The intense blue light absorption and high PLQY (92.6 %) inspire us to assemble Mn-1 as a blue-light-excited white light-emitting diode (WLED). The WLED has a minimized trade-off among luminous efficacy (182 lm/W), color-rendering index (82) and CCT (4536 K), which is achieved by the trichromatic combination (blue light chip, green (Ba, Sr)2SiO4:Eu2+, red Mn-1) and the red emission edge below 700 nm. The luminous efficacy of 182 lm/W is the highest among the previous WLEDs based on the lead-free metal halides, comparable to the market standard (185 lm/W) in 2020 set by The United States Department of Energy. In addition, the water-soluble Mn-1 further gives potential applications in X-ray scintillators, luminescent ceramics, flexible films and luminescent imaging agents. The discovery of tetranuclear metal halide clusters establishes a new strategy for constructing promising emissive materials.

Use of sisal industrial waste (Agave sisalana Perrine) in sustainable and multifunctional cosmetic products.

Sisal is a common stiff fibre produced around the world, corresponding to approximately 70% of the commercial production of all fibres of this type. The fibres are extracted from the leaves of Agave sisalana, from which approximately 4% of their weight is obtained, with the remaining 96% considered to be residues from the process of the sisal industry. The objective of this work was to obtain a polyphenol-enriched extract from the A. sisalana residue by ultrasonically assisted extraction, characterize it chemically, evaluate invitro antioxidant activity, and develop safe and stable photoprotective formulations for future application in cosmetic preparations. Ultrasonic extraction of solid plant material was performed using 50% ethanol/water (v/v). The extract was chemically characterized by high-performance liquid chromatography equipment associated with classical molecular networking and evaluated for invitro antioxidant activity by different methodologies. Ten formulations were prepared, varying the component concentrations and the shear time. The 1.0% sisal extract was incorporated into the most stable formulations, and preliminary and accelerated stability were evaluated. The emulsions were investigated for safety by assessment of primary accumulated dermal irritability and sensitization and a dermatological clinical study of phototoxicity and photosensitization. The photoprotective formulations containing or not containing the extract that were stable after 90 days had their invivo sun protection factor (SPF), UVA protection factor, critical wavelength, and protection against visible and blue light determined. Ultrasound extraction using 50% ethanol/water (EH 50) as an extractor vehicle showed the best yield. The extract exhibited a concentration of phenolic compounds (77.93 mg of equivalent to the standard gallic acid/g) and showed invitro antioxidant activity. Emulsions without and with 1.0% sisal extract remained stable and safe. The addition of the extract to the photoprotective formulation statistically increased the SPF when compared to the formulation without the extract and offered protection against UVA radiation, critical wavelengths, and absorption of visible and blue light. Based on the findings, the solid residue of A. sisalana may be indicated as a component of photoprotective and antioxidant cosmetic formulations.

Photocycle alteration and increased enzymatic activity in genetically modified photoactivated adenylate cyclase OaPAC

Photoactivated adenylate cyclases (PACs) are light activated enzymes that combine blue light sensing capacity with the ability to convert ATP to cAMP and pyrophosphate (PPi) in a light-dependent manner. In most of the known PACs blue light regulation is provided by a blue light sensing domain using flavin which undergoes a structural reorganization after blue-light absorption. This minor structural change then is translated toward the C-terminal of the protein, inducing a larger conformational change that results in the ATP conversion to cAMP. As cAMP is a key second messenger in numerous signal transduction pathways regulating various cellular functions, PACs are of great interest in optogenetic studies. The optimal optogenetic device must be "silent" in the dark and highly responsive upon light illumination. PAC from Oscillatoria acuminata is a very good candidate as its basal activity is very small in the dark and the conversion rates increase 20-fold upon light illumination. We studied the effect of replacing D67 to N, in the blue light using flavin domain. This mutation was found to accelerate the primary electron transfer process in the photosensing domain of the protein, as has been predicted. Furthermore, it resulted in a longer lived signaling state, which was formed with a lower quantum yield. Our studies show that the overall effects of the D67N mutation lead to a slightly higher conversion of ATP to cAMP, which points in the direction that by fine tuning the kinetic properties more responsive PACs and optogenetic devices can be generated.

Broadband Short-Wave Infrared-Emitting MgGa2O4:Cr3+, Ni2+ Phosphor with Near-Unity Internal Quantum Efficiency and High Thermal Stability for Light-Emitting Diode Applications.

Blue InGaN chip-pumped short-wave infrared (SWIR) emitters have aroused tremendous attention and shown emerging applications in diverse fields such as healthcare, retail, and agriculture. However, discovering blue light-emitting diode (LED)-pumped SWIR phosphors with a central emission wavelength over 1000 nm remains a significant challenge. Herein, we demonstrate the efficient broadband SWIR luminescence of Ni2+ by simultaneously incorporating Cr3+ and Ni2+ ions into the MgGa2O4 lattice, with Cr3+ as the sensitizer and Ni2+ as the emitter. Because of the strong blue light absorption of Cr3+ and high energy transfer efficiency to Ni2+, the obtained MgGa2O4:Cr3+, Ni2+ phosphors show intense SWIR luminescence with a peak wavelength at 1260 nm and a full width at half maximum (FWHM) of 222 nm under the excitation of blue light. The optimized SWIR phosphor presents an ultra-high SWIR photoluminescence quantum efficiency of 96.5% and outstanding luminescence thermal stability (67.9%@150 °C). A SWIR light source has been fabricated through a combination of the prepared MgGa2O4:Cr3+, Ni2+ phosphor and a commercial 450 nm blue LED chip, delivering a maximum SWIR radiant power of 14.9 mW at 150 mA input current. This work not only demonstrates the feasibility of developing broadband high-power SWIR emitters using converter technology but also presents new insights into the importance of SWIR technology.

Bilirubin- and Blue-Green Light-Induced Damage of Human Erythrocytes

Phototherapy is widely used for neonatal hyperbilirubinemia treatment; however, the most important but not completely recognized issue is the determination of the optimal spectral range of light that provides an effective reduction of bilirubin level in the blood of a newborn with minimal adverse side effects. This study demonstrates that the exposure of radiation from LED sources of blue (emission wavelength λ max = 463 nm, FWHM 20 nm) and green (λ max = 517 nm, FWHM 38 nm) spectral regions to the erythrocyte suspension with the same energy dose (D = 14.4 J/cm 2 ) leads to approximately equally effective hemolysis of erythrocytes. It is concluded that the damage of erythrocyte membranes is caused by the excitation of endogenous porphyrin and flavin photosensitizers contained in the cells in low concentrations, but characterized by high efficiency of singlet oxygen generation. When bilirubin is added to the erythrocyte suspension, a spontaneous (dark) erythrocyte hemolysis intensifies, but the light-induced hemolysis slows down (compared to cells containing no bilirubin). Under the same conditions, the leakage of potassium ions from light-exposed erythrocytes is accelerating, with the light of green spectral region has a more pronounced effect, despite more intense absorption of blue light by bilirubin localized in cells.

55‐2: Invited Paper: Quantum Dot Color Conversion for Displays

Quantum dot (QD) color conversion has recently been demonstrated in commercial QD‐OLED displays on the market exhibiting exceptional color gamut coverage, brightness, black levels, and viewing angles. To continue developing QDs for a wide range of future display technologies, two key aspects remain under study. First, how can blue light absorption be maximized for small pixel formats (&lt;10 μm) requiring thin QD color conversion layers and second, as pixel sizes shrink and display brightness increases, how can these materials remain stable under high blue‐light excitation flux (up to 5W/cm 2)? Here we describe experiments addressing these two areas of continued development for heavy‐metal free QDs.