Light Diode Research Articles

Judicious design solutions for zero energy school buildings in hot climates

The concept of net-zero energy, with its holistic consideration of energy-efficient passive, active, and renewable energy systems, is a critical step toward decarbonizing the built environment. This work aims to assess the feasibility of net-zero energy schools in hot climates and propose practical and realistic design solutions. The design of a net-zero energy school was developed and analyzed using DesignBuilder software in hot-humid, hot-dry, and warm-humid climatic zones in Oman. A multiphase methodology was followed, including data collection, an energy audit, fieldwork measurements, and energy simulation modeling. Integrating judicious passive design strategies such as thermal insulation for walls and roofs besides high-performance windows resulted in moderate potential reductions in energy cost and consumption in all climatic zones. Considering active design strategies like light-emitting diode (LED) lights, lighting control, and variable refrigerant volume/variable refrigerant flow (VRV/VRF) air conditioning systems resulted in additional reductions in energy cost and consumption. For the energy cost, the reductions were estimated at 29.9%, 29.5%, and 25.9% in the hot-humid, hot-dry, and warm-humid climatic zones, respectively. The corresponding reductions in energy consumption reached 28.53%, 27.90%, and 25.14%. Integrating a photovoltaics (PV) system aiming to reach the net-zero energy status supplied the school with demanded energy and managed to export 42.78%, 43.53%, and 45.75% to the national grid in the hot-humid, hot-dry, and warm-humid climatic zones, respectively. Similar reductions were achieved for CO2 emissions and energy costs.

The Effects of Light Treatments on Growth and Flowering Characteristics of Oncidesa Gower Ramsey ‘Honey Angel’ at Different Growth Stages

In our previous work, we observed that Oncidesa Gower Ramsey ‘Honey Angel’ (HA) plants became stunned on hot summer afternoons, and the seasonal trend in solar radiation affected its production schedule by limiting flower yield and quality. The objective of this work was to study the growth and flowering characteristics of HA pseudobulbs at three stages of growth (G2–G4) in response to three types of light-emitting diode (LED) lighting treatments, including full spectrum (FS), deep red/white-medium blue (DR/W-MB), and deep red/white-low blue (DR/W-LB), for two additional time intervals. The supplementary LED lighting time intervals (S) applied daily were carried out for 1 h (4:00~5:00 a.m., as S-1) or 2 h (4:00~6:00 a.m., as S-2) from March to September, 2022. Natural light without supplemental lighting was the control. The length of pseudobulb (PL), width of pseudobulb (PW), thickness of pseudobulb (PT), length of inflorescence (FL), number of branches (FB), number of florets (FN), and days to flowering (FD) per plant were recorded andcalculated when 80% of florets became mature. Light treatments significantly affected all pseudobulb growth and flower quality traits at different Gs, especially pseudobulb length (PL) and flower number (FN) under different LED types and lighting time intervals. MB-1 treatment promoted PT at both G3 and G4, whereas MB-2 treatment increased PW at both G2 and G4. Both MB-1 and LB-1 treatments had augmented effects on PL, respectively, at G2 and G3. The PW, FL, FB, and FN increased with additional light time and reached maxima under MB-2 treatment at G4 compared to other treatments and controls. Early flowering and an increased number of flowers at G4 were observed in plants grown under MB-2 treatment. Controlling light quality and supplementary light time intervals enables the production of HA plants with the desired growth and flowering quality characteristics of the pseudobulbs.

Design and Performance Analysis of Automobile Headlamp Based on Light-Emitting Diode

As a vital component of the automobile headlamp, its design is not only related to power loss but also affects the appearance of the automobile. Most importantly, its design directly affects the night lighting effect and driving safety. Compared with the traditional headlamp light source, light-emitting diode (LED) light source has the advantages of long lifespan, small size, fast response, flexible design, flexible control, and so on. Based on this, this study designs high-power white LED automobile headlamps, adopts the commonly used reflector design technology, and puts forward the design scheme of the lighting group system. This scheme relies on a reflector for light distribution, without needing a baffle or lens with light distribution patterns. The optical design software TracePro and the three-dimensional design software PROE are used to simulate and design the reflectors of low and high beams, respectively. The simulation results of the reflector of the low beam show that more than 490000 rays of light reach the filament shield, with a light utilization rate of over 95%. The horizontal cut-off line and 15° light and dark cut-off lines are clearly visible, and the front window material is closed. Considering this factor, the illumination distribution of the low beam meets relevant national regulations. The high beam reflector simulation results reveal that over 960000 light rays reach the filament shield, with a more than 95% light utilization rate. The light spot is symmetrical. If the front window material is polycarbonate and not coated, the absorption and scattering of light are ignored, and the transmittance of the beam through the two optical surfaces achieves 90%.

Library Visitor Noise Monitoring System Design With Warning Using LED and Telegram

Abstract. The library supports education and is used as a place to learn and gain knowledge. To maximize its use, visitors need comfort by not making noise or upheaval that can disturb other visitors. According to the decision of the Ministry of Environment in 1996, the maximum standard for noise levels in libraries is 55 dB. This research was conducted to design a tool that can monitor the noise that occurs in the library by providing information on room conditions usingLED (Light Emitting Diode) lights, LCD (Liystal Displayquid Cr), and giving notifications to librarians in the form of messages on the Telegram application if the noise exceeds the limit. maximum. The tool is designed using ESP32 as a control, a GY-MAX4466 sensor to detect sound, and the output system uses red, yellow, and greenLED (Light Emitting Diode), LCD (Liquid Crystal Display) 16x2, and the Telegram application. The results of this study concluded that the noise monitoring system was running well, with a GY-MAX4466 sensor error rate of 0.4%, and the best R Square value was obtained at a distance of 1 meter from the sound source with an R Square value of 0,7202.

Broadband emission characteristics and WLED application of self-activated YMZn3AlO7 (M=Ca, Sr, Ba) phosphors

In this study, a non-activated ion-doped full-spectrum emission phosphor for white light-emitting diode (WLED) lighting is proposed using oxygen defect engineering. The YMZn3AlO7 (M = Ca, Sr, Ba) phosphors with "114″ structure were prepared via a high-temperature solid-state reaction. Under excitation with 373 nm ultraviolet (UV) light, YSrZn3AlO7 in YMZn3AlO7 (M = Ca, Sr, Ba) exhibited the highest emission intensity and formed a wide yellow emission band centred at 563 nm. The full width at half maximum of the YSrZn3AlO7 phosphor was 172.6 nm. A theoretical model based on the designed oxygen vacancies was proposed to determine the self-activated luminescence mechanism. Density functional theory calculations revealed that oxygen vacancies lead to the generation of new energy levels. Electron paramagnetic resonance experiments further confirmed that the luminescence originated from oxygen vacancies. Eventually, a warm WLED device ((x, y) = (0.4057, 0.4359)) with a correlated color temperature of 3814 K and a relative color rendering index of 83 was successfully prepared using the YSrZn3AlO7 phosphor and a 365 nm UV LED chip. These results suggest that YSrZn3AlO7 is a promising WLED phosphor and provide new insights into the application of self-activated phosphors in WLED.

Light-Emitting Diode Light Quality Influences Germination and Sprout Characteristics of Motherwort

Motherwort (Leonurus japonicus Houtt) is an important medicinal plant known for its excellent antioxidant properties. Nonetheless, in South Korea, its availability remains limited due to the challenge of low seed germination rates, affecting field production. To tackle this problem, it is imperative to focus on controlled production methods. In our study, we conducted experiments in a laboratory setting, employing various combinations of light-emitting diode (LED) lights to cultivate motherwort. The influence of LED light quality on seed germination, initial growth, and functionality of motherwort is evaluated. The germination rate of motherwort ranged from 36.1 ± 7.35% to 75.0 ± 1.60%, and the highest value was observed in the red LED 100% treatment. The mean shoot length also varied depending on LED light quality. The longest shoot length (3.45 ± 0.13 g) was obtained in the red LED 100% treatment. The highest shoot weight (0.266 ± 0.011 cm) and root weight (0.051 ± 0.008 cm) were obtained in the red LED 70% and blue LED 30% mixed treatment. The total phenolic content of the motherwort sprout ranged from 2.50 ± 0.30 mg GAE/g to 3.01 ± 0.09 mg GAE/g, with the highest value from the white LED (control) treatment, but no significant differences were observed among the treatments. The red LED 30% and blue LED 70% mixed treatment showed the highest total flavonoid content (11.62 ± 0.79 mg QE/g) and DPPH radical scavenging activity (57.64 ± 2.95%). The red LED 70% and blue LED 30% mixed treatment had a similar level of DPPH scavenging activity as the control, and there was no positive or negative effect on the functionality of motherwort sprout. Overall, the results suggest that the red LED 70% and blue LED 30% mixed treatment can be effectively used to increase productivity in motherwort without decreasing its important quality.

Evaluation of the solar-powered Silver Bullet 2.1 (Lumin 8) light trap for sampling malaria vectors in western Kenya

BackgroundCenters for Disease Control and Prevention (CDC) light traps are widely used for sampling mosquitoes. However, this trap, manufactured in the USA, poses challenges for use in sub-Saharan Africa due to procurement costs and shipping time. Traps that are equally efficient than the CDC light trap, but which are amenable for use in remote African settings and made in Africa, are desirable to improve local vector surveillance. This study evaluated a novel solar-powered light trap made in South Africa (Silver Bullet trap; SB), for its efficiency in malaria vector sampling in western Kenya.MethodsLarge cage (173.7 m3) experiments and field evaluations were conducted to compare the CDC-incandescent light trap (CDC-iLT), CDC-UV fluorescent tube light trap (CDC-UV), SB with white diodes (SB-White) and SB with UV diodes (SB-UV) for sampling Anopheles mosquitoes. Field assessments were done indoors and outdoors following a Latin square design. The wavelengths and absolute spectral irradiance of traps were compared using spectrometry.ResultsThe odds of catching a released Anopheles in the large cage experiments with the SB-UV under ambient conditions in the presence of a CDC-iLT in the same system was three times higher than what would have been expected when the two traps were equally attractive (odds ratio (OR) 3.2, 95% confidence interval CI 2.8–3.7, P < 0.01)). However, when the white light diode was used in the SB trap, it could not compete with the CDC-iLT (OR 0.56, 95% CI 0.48–0.66, p < 0.01) when the two traps were provided as choices in a closed system. In the field, the CDC and Silver Bullet traps were equally effective in mosquito sampling. Irrespective of manufacturer, traps emitting UV light performed better than white or incandescent light for indoor sampling, collecting two times more Anopheles funestus sensu lato (s.l.) (RR 2.5; 95% CI 1.7–3.8) and Anopheles gambiae s.l. (RR 2.5; 95% 1.7–3.6). Outdoor collections were lower than indoor collections and similar for all light sources and traps.ConclusionsThe solar-powered SB trap compared well with the CDC trap in the field and presents a promising new surveillance device especially when charging on mains electricity is challenging in remote settings.

Effect of tungsten oxide as a buffer layer on the device performance and stability of organic light diodes

Effect of tungsten oxide as a buffer layer on the device performance and stability of organic light diodes

Compensation of adverse growing media effects on plant growth and morphology by supplemental LED lighting.

There is an increasing interest in alternatives to peat in growing media due to environmental constraints. However, plants grown in peat substitutes often show impaired growth compared to plants grown in peat-based media. Hence, it would be interesting to know whether these deficiencies can be compensated by supplementing other growth factors, e.g. light. The present study aims to investigate the interactive nature between growing media and supplemental lighting on plant growth and morphology, and to examine whether supplemental light emitting diode (LED) lighting may compensate adverse growing media effects. Basil (Ocimum basilicum L.) and Chinese cabbage (Brassica rapa subsp. pekinensis) were grown in different growing media consisting of peat, green compost, coconut pulp, wood fibre, perlite and sphagnum moss under blue, red and far-red supplemental LED lighting. We found significant interactions between growing media and supplemental photosynthetically active radiation (PAR) on plant growth, morphology and development. At low light intensities, peat-based and substituted growing media performed similarly, whereas with increasing light intensities the peat-based growing media significantly outperformed their alternatives. The substrate choice determines the required amount of supplemental light to compensate for adverse growing media effects and the amount varies depending on plant species and season. Thereby, it was indicated that red light alleviates adverse growing media effects best. We also found that far-red light is not effective when background PAR is low and becomes more effective under high background PAR. The implications and prospects of the results are discussed.

Identification and Characterization of Mercury Contamination in Vegetables and Herbs Cultivated on a Commercial Vertical Indoor Farming System with Light-Emitting Diode Lighting: Unveiling an Unusual Food Safety Risk of Some Improperly Manufactured High-Density Agricultural Production Systems.

Artificial grow lights, such as light-emitting diodes (LEDs) and fluorescent grow lights, are commonly used in modern day indoor farming, citing advantages in energy efficiency and a higher controlled environment. However, the use of LEDs poses a risk in mercury contaminations as a result of its production process, specifically LEDs with polyurethane encapsulates that were traditionally produced using mercury resins as a catalyst. A total of 10.0 ppm of mercury was detected in a curly kale sample harvested from an indoor hydroponic vegetable farm, exceeding Singapore Food Regulation's limit of 0.05 ppm. Vegetables, farming inputs, and surface swabs from the affected farm were analyzed using wet acid digestion followed by cold vapor atomic absorption spectroscopy analysis. The investigation found high concentrations of mercury in the LED encapsulant, and the encapsulant material was identified to be polyurethane by Fourier transform infrared spectroscopy and pyrolysis-gas chromatography-mass spectrometry analysis, indicating the source of mercury contamination to be the LED polyurethane encapsulant.

Multifunctional metal (Ag, Bi)-organic frameworks: a versatile platform for photocatalytic degradation, CO2 and N2 reduction, and enhanced antibacterial applications

The facile synthesis of a bimetallic-organic framework is successfully established to portray an efficient catalyst in photocatalytic degradation and photoreduction of nitrogen (N2) and carbon dioxide (CO2) and with antibacterial properties. In the current study, a novel B-BTC (where B represents Ag and Bi) organic framework was successfully synthesized and opted for advanced characterizations. The high-resolution transmission electron microscopy and X-ray photon spectroscopy illustrate the heterostructure formation, whereas X-ray diffraction spectroscopy, zeta sizer, and zeta potential were used to reveal the crystallinity, polydispersity, and average size of the nanomaterial. The material was characterized for photoluminescence analysis to understand the recombination rate and has been compared with the Bi-organic framework. B-BTC was further opted to determine the photocatalytic efficacy, through photocatalytic degradation of amoxicillin (AMX), photocatalytic reduction of N2 to ammonia (NH3), photoreduction of CO2, and antibacterial disinfection. The catalyst showcased ∼90% degradation of AMX under light-emitting diode light irradiation for 60 min. Successful photoreduction of N2 and CO2 showcases a fair generation of NH3 and value-added hydrocarbons, respectively. For each photocatalytic application, a mechanism has been knitted for understanding the overall reactions concerning the proposed reactions. Interestingly, the catalyst also showcased excellent antibacterial activity toward Escherichia coli and Staphylococcus aureus, with a proposed mechanism.

Amorphous molybdenum sulfide/polymeric carbon nitride composite with multiple interfaces for boosting photoelectrochemical water splitting performance

Rational interface design is an important way to improve the photoelectrochemical activity of catalysts in the sustainable energy and the environment. Herein, we simultaneously realize the construction of polymeric carbon nitride (PCN)-based homojunction (HPCN) and amorphous molybdenum sulfide (a-MoSx) /PCN heterojunction (a-MoSx/HPCN) in the composite catalyst system by one-pot calcination. The presence of a-MoSx was confirmed by X-ray photoelectron spectroscopy (XPS) and element mapping. X-ray diffraction (XRD) and transmission electron microscopy (TEM) revealed the amorphous characteristics of molybdenum sulfide. The photoluminescence (PL) spectroscopy indicated that the photo-generated carrier recombination of composite is effectively inhibited after constructing the homojunction and loading molybdenum sulfide. The confined effect of the PCN matrix induced the formation of ultrafine size a-MoSx, and its co-catalyst function is prominent. The optimized composite catalyst showed obvious boosting activity in photoelectrochemical water slitting. Photocathode current of −161 μA cm−2 (0 V vs. RHE) and photoanode current of 10 μA cm−2 (1.23 V vs. RHE) are almost 12 and 5 times than single PCN homojunction under the irradiation of 25 W light-emitting diode light source. This boosted activity can be attributed to the multiple interface effect of the n-n junction of PCN/PCN and the p-n junction of a-MoSx/PCN as well as the co-catalysis of amorphous molybdenum sulfide. The synergies between various merits effectively improved the absorption of visible light, the separation of photogenerated electrons and holes, and the addition of more reactive sites. This paper provides a new idea for interface engineering of PCN-based composite photoelectrode.

A non-inverting single-switch buck-boost converter based LED driver

&lt;span lang="EN-US"&gt;This paper focuses on a single-switch buck-boost (SSBB) converter for light emitting diode (LED) lighting applications. The proposed LED driver with power factor correction (PFC) shows enhanced performance in terms of input power factor, efficiency and reduced voltage stress across the switch. The presented LED driver is operated in discontinuous conduction mode (DCM). The input PFC is carried out using average current mode control (ACMC) and the controller is optimized using artificial bee colony (ABC) algorithm. A hardware prototype of 50W LED driver with ACMC for PFC is implemented using a programmable interface circuit (PIC) microcontroller. The experimental results are presented and the performance is compared with a conventional buck boost LED driver. The proposed SSBB LED driver achieves an input power factor of 0.96 with an efficiency of 98%.&lt;/span&gt;

Efficacy of Photodynamic Therapy in the Treatment of Oral Premalignant Lesions: A Systematic Review

Abstract Photodynamic therapy (PDT) is considered a contemporary effective treatment option for oral premalignant lesions. This systematic review aims to evaluate the usefulness of PDT for the treatment of oral premalignant lesions. The focused question was “Is PDT effective in the treatment of oral premalignant lesions?” A literature search was made in PubMed/Medline and Google Scholar databases using different combinations of the following keywords: photodynamic therapy, oral premalignant lesions, oral leukoplakia (OL), erythroplakia, oral erythroleukoplakia (OEL), oral verrucous hyperplasia (OVH), and oral lichen planus (OLP). Review articles, preclinical studies, case reports, commentaries, letters to the editor, unpublished articles, studies on photodynamic therapy used in areas other than oral cavity, and articles published in languages other than English were excluded. The relevant information were summarized. Initial results were 23. Twenty-two studies were included. Oral premalignant lesions, which were investigated, were OL, erythroplakia, OEL, OVH, and OLP. The studies used either laser light or light-emitting diode. Photosensitizers used were aminolevulinic acid, chlorine-e6, meta-tetrahydroxyphenylchlorin, methylene blue, toluidine blue, methyl 5-aminolevulinate cream, and phenothiazine chloride. Study outcomes and recurrence rates were evaluated. PDT is an effective treatment option. Topical PDT is an easy-to-perform technique, well-tolerated treatment with encouraging achievements in the treatment of premalignant lesions.

A Flexible Broadband Visible Light Plasmon‐Absorber Based on a 2D Monolayer of Au‐Nanoparticle/TiO2‐Nanowire Core–Shell Heterostructures

AbstractPlasmon‐induced hot carrier transfer is a promising approach for photoelectric applications, but its practical application is often hindered by its relatively narrow absorption bandwidth and low light harvesting at visible wavelengths. This work reports a broadband visible light plasmon‐absorber based on a dandelion‐like hierarchical metal‐semiconductor Au‐TiO2 core–shell nanostructure where each Au nanoparticle (AuNP) core is covered by an optically transparent mesh‐shell composed of TiO2 nanowires (TNWs) (denoted as AuTNW‐dCS). These AuTNW‐dCSs are assembled to form a 2D arrayed plasmonic monolayer by connecting adjacent AuNPs with cross‐linked TiO2 NWs, which can induce a remarkable broadband absorption in the visible spectrum of 500–700 nm. Driven by a wide light adsorption range, improved hot‐electron carriers, and excellent analyst's immobilization capability, the AuTNW‐dCS based photoelectric immunosensor owns excellent performance for alpha‐fetoprotein detection in human serum, with a practical linear range of 0.1–1000 ng mL−1, a low detection limit of 0.1 ng mL−1, and satisfying selectivity under visible light‐emitting diode light irradiation. This work enlightens the prospective research on the use of metal/semiconductor core–shell heterostructures as photoactive materials for sensing applications. Additionally, it gives an impetus for developing flexible nanofilms based on plasmonic metal/semiconductor nanohybrids, beneficial for building wearable point‐of‐need platform.

Increasing catches of adult moth pests (Lepidoptera: Tortricidae) in pome fruit with low‐intensity LED lights added to sex pheromone/kairomone lure‐baited traps

AbstractStudies of moth pests (Lepidoptera: Tortricidae) of pome fruit in Washington State, USA, evaluated the addition of low‐intensity light‐emitting diode (LED) lights to traps baited with sex pheromone or kairomone lures. Species included codling moth (CM), Cydia pomonella (L.), oriental fruit moth (OFM), Grapholita molesta (Busck), oblique banded leafroller (OBLR), Choristoneura rosaceana (Harris), and eye‐spotted budmoth (ESBM), Spilonota ocellana (Denis and Schiffenmüller). Lures included (E,E)‐8,10‐dodecadien‐1‐ol (codlemone) plus (E,Z)‐2,4‐ethyl decadienoate (pear ester) and acetic acid (AA) (Combo) and a blend of pear ester, (E)‐4,8‐dimethyl‐1,3,7‐nonatriene, pyranoid linalool oxide, and AA (4K) for CM; a three‐component OFM sex pheromone ((E)‐8‐dodecen‐1‐yl‐acetate, (Z)‐8‐dodecen‐1‐yl acetate, and (Z)‐8‐dodecen‐1‐ol) plus codlemone and terpinyl acetate plus AA for OFM; and 2‐phenylethanol and AA for OBLR and ESBM. Traps baited with only LEDs were not attractive for any of these tortricids. The addition of a LED to lure‐baited traps increased male and female catches 2‐12‐fold across the four pest species. The proportional increase in CM catches with the LEDs was similar with both the Combo and 4K lures. Traps baited with the 4K lure caught significantly more CM with a UV LED than with either blue or green LEDs. The proportion of females caught in traps that were mated did not change with the use of the lights across species. Significantly more CM of both sexes were caught in the adhesive on the side of the liner nearest the LED. The addition of LEDs sometimes increased the by‐catch of minute insects, but liners' saturation was never a factor impacting targeted moth catch. Adding the LED light significantly increased the catch of ESBM in CM‐baited traps and CM in OFM‐baited traps, respectively. The development of inexpensive, dual‐modality traps that add a light stimulus to a kairomonal‐based lure may improve direct control of these key orchard pests via female removal.

Europium- and Black Phosphorus-Functionalized Porphyrin as an l-Arginine Sensor and l-Arginine-Activated PDT/PTT Agent for Bacterial Treatment.

The attenuation of bacterial metabolism provides an adjunct to the treatment of bacterial infections. To develop a bacterial eradication agent, a bioactivatable material (BP@Eu-TCPP) was designed and synthesized by coordination and reduction of europium(III) with thin-layer black phosphorus (BP) and tetrakis (4-carboxyphenyl) porphyrin (TCPP). The existence of the P-Eu bond and Eu2+ 3d5/2 in X-ray photoelectron spectroscopy confirmed the successful synthesis of BP@Eu-TCPP. This material showed high fluorescence sensitivity to l-Arginine (l-Arg) and the main binding ratio of BP@Eu-TCPP to l-Arg was ca. 1:2 or 1:3, with the limit of detection of 4.0 μM. The material also showed good photothermal properties and stability, with a photothermal conversion efficiency of 37.3%. Although metal coordination has blocked the generation of 1O2, the addition of l-Arg to BP@Eu-TCPP can restore 1O2 generation upon red light-emitting diode (LED) light irradiation due to the formation of water-soluble Arg-TCPP species. Additionally, BP@Eu-TCPP was enabled to change the bacterial membrane and interfered with the bacterial iron absorption that effectively contributes to bacterial eradication. Such BP@Eu-TCPP is promised to be a novel material for the detection of l-Arg and l-Arg-activated photodynamic therapy.

Lysosome-targeted carbon dots with a light-controlled nitric oxide releasing property for enhanced photodynamic therapy

The reactive oxygen species (ROS) generation efficiency is always limited by the extreme tumor microenvironment (TME), leading to unsatisfactory antitumor effects in photodynamic therapy (PDT). As a promising gas therapy molecule, nitric oxide (NO) is independent of oxygen and could even synergize ROS to enhance the therapeutic effect. However, the short half-life, instability, and uncontrollable release of exogenous NO limited the application of tumor synergistic therapy. Herein, we reported a novel kind of red-emissive carbon dots (CDs) that was capable of lysosome-targeted and light-controlled NO delivery. The CDs were synthesized by using metformin and methylene blue (MB) via a hydrothermal method. The obtained metformin-MB CDs (MMCDs) exhibited a higher 1O2 quantum yield and NO generation efficiency under light emitting diode (LED) light irradiation. Noteworthily, the 1O2 could further in situ oxidize NO into peroxynitrite anions (ONOO−), which own the higher cytotoxicity against cancer cells. Cell experiments indicate that MMCDs could destruct lysosome membrane integrity and kill almost 80% of HepG2 cells under light irradiation while very low cytotoxicity in the dark. Moreover, MMCDs significantly decreased tumor volume and weight after phototherapy in hepatoma HepG2-bearing mice. Our study provides a new strategy for light-controlled NO generation as well as precise lysosome-targeting for enhancement of PDT efficiency.

Organic light‐emitting diode behaviors of some synthesized platinum(II)‐based complexes

AbstractOrganic light‐emitting light diodes (OLEDs) have been increasingly used in displays, replacing liquid‐crystal displays (LCD) and light‐emitting diodes (LEDs) panels. The increase in commercial use of OLED has led to the search for OLED with high performance. For that reason, the OLED properties of monomers and dimers of some synthesized platinum(II)‐based complexes were estimated by using different computational chemistry tools with different codes. The electron/hole reorganization energies, the adiabatic/vertical ionization potentials, the adiabatic/vertical electron affinities, the chemical hardness values, the dipole moments, the frontier orbital shapes/energy levels, the energy gaps, the emission wavelengths, spin‐orbit matrix elements, the rates of reverse intersystem crossing and intersystem crossing of the investigated complexes were determined. From the theoretically obtained data, it was found that Pt(hppz)2 and Pt(fppz)2 complexes can be used as electron transfer material. Furthermore, it was stated that Pt(f2bipz)(bpy) is both electron‐blocking layer and hole blocking layer materials. Moreover, it was noted that that PtOEP complex can be utilized as a good electron injection layer and hole injection layer material. Addition to these, it was emphasized that that Pt(f2bipz)(bpy) can be considered as a good candidate for near infrared organic light emitting diodes and thermal activated delayed fluorescent organic light emitting diodes. In light of computational chemistry, it should be expected that the study will provide a great contribution to studies related to organic light emitting diodes.

Self-Healable, Adhesive, Anti-Drying, Freezing-Tolerant, and Transparent Conductive Organohydrogel as Flexible Strain Sensor, Triboelectric Nanogenerator, and Skin Barrier.

Conductive hydrogels have attracted tremendous interest in the construction of flexible strain sensors and triboelectric nanogenerators (TENGs) owing to their good stretchability and adjustable properties. Nevertheless, how to simultaneously achieve high transparency, self-healing, adhesion, antibacterial, anti-freezing, anti-drying, and biocompatibility properties through a simple method remains a challenge. Herein, a transparent, freezing-tolerant, and multifunctional organohydrogel (PAOAM-PDO) as electrode for strain sensors and TENGs was constructed through a free radical polymerization in the 1,3-propanediol (PDO)/water binary solvent system, in which oxide sodium alginate, aminated gelatin, acrylic acid, and AlCl3 were used as raw materials. The obtained PAOAM-PDO exhibited good transparency (>90%), self-healing, adhesiveness, antibacterial property, good conductivity (1.13 S/m), and long-term environmental stability. The introduction of PDO endowed PAOAM-PDO with freezing resistance with a low freezing point of -60 °C, and PAOAM-PDO could serve as a protective skin barrier to prevent frostbite at low temperature. PAOAM-PDO could be assembled as strain sensors to monitor heterogeneous human movements with high strain sensitivity (gauge factor of 7.05, strain = 233%). Meanwhile, PAOAM-PDO could be further fabricated as a TENG with a "sandwich" structure in single electrode mode. Moreover, the resulting TENG achieved electrical outputs with simple hand tapping and served as a self-powered device to light light-emitting diodes. This work displays a feasible strategy to build environment-tolerant and multifunctional organohydrogels, which possess potential applications in the wearable electronics and self-powered devices.