Diode Devices Research Articles

Synthesis, structural and optical properties of a novel double perovskite Gd[formula omitted]MgTiO[formula omitted]: Dy[formula omitted] phosphors for LED applications

Dy3+ doped Gd2MgTiO6 (GMT) phosphors were were fabricated using the high temperature solid state method in this study. Fluorescence, UV-visible spectrometer, X-ray photoelectron spectrometer, and Transient fluorescence spectrometer. The results show that the structures of the series of phosphors belong to the monoclinic crystal system, and Dy3+ was successfully incorporated into the GMT host without affecting its structure. The samples emitted extremely strong blue and yellow light, which are the transitions derived from 4H9/2 to 6H15/2 (482 nm) and 6H13/2 (575 nm) levels, respectively. The sample shows obvious effects of concentration, GMT: 0.11Dy3+ phosphor has the best photoluminescence (PL) intensity 7.148×105, lifetime is 0.16 ms, and an internal quantum efficiency (IQE) is 2.1%. The Dy3+ doped sample has a larger energy band gap of 4.11 eV. The prepared samples exhibit color coordinates in proximity to that of standard white light, which indicates that the phosphor GMT: Dy3+ can be applied to white light phosphors and light-emitting diode (LED) devices.

The role of light emitting diode in wound healing: A systematic review of experimental studies.

Wounds represent a growing global issue demanding increased attention. To expedite wound healing, technologies are under development, and light emitting diode (LED) devices of varying wavelengths are being explored for their stimulating influence on the healing process. This article presents a systematic literature review aiming to compile, organize, and analyze the impacts of LED devices on wound healing.This review is registered on the PROSPERO platform [CRD42023403870]. Two blinded authors conducted searches in the Pubmed, Web of Science, Scopus, Embase, and ScienceDirect databases. In vitro and in vivo experimental studies assessing LED utilization in the wound healing process were included.The search yielded 1010 studies, of which 27 were included in the review. It was identified that LED stimulates different healing pathways, promoting enhanced cell proliferation and migration, angiogenesis stimulation, increased collagen deposition, and modulation of the inflammatory response.Thus, it can be concluded that the LED stimulates cellular and molecular processes contingent on the utilized parameters. The effects depend on the standards used. Cell migration and proliferation were better influenced by green and red LED. The extracellular matrix components and angiogenesis were regulated by all wavelengths and the modulation of inflammation was mediated by green, red, and infrared LEDs.

Two substitution strategies realize single-phase full-spectrum emission in Ca10Na(PO4)7:Eu2+ phosphors for WLED

Herein, a variety of single-phase full-spectrum emission phosphors doped with Eu2+ were synthesized. Under the 350 nm excitation, as K+ and Y3+ were introduced into Ca10Na(PO4)7 (CNP):1.5%Eu2+, respectively, the emission color of Ca9.85KyNa(1-y) (PO4)7:1.5%Eu2+ (0 ≤ y ≤ 1.0) was tuned from yellow to cyan, while that of Ca(9.85-z)NaY0.667z (PO4)7:1.5%Eu2+ (0 ≤ z ≤ 1.0) was tuned from yellow to green. The internal quantum yield (QY) of Ca9·85K0·4Na0·6(PO4)7 (CKNP):1.5%Eu2+ and Ca9·45NaY0·267(PO4)7 (CNYP):1.5%Eu2+ reached 47.47 % and 27.11 %, respectively. The introduction of K+ or Y3+ made Eu2+ selectively occupy the Ca sites and led to changes in the local environment of Eu2+, allowing for spectral tuning emission. In addition, the luminescence intensity of the samples retained 54.59 % and 31.34 % of their room temperature values. Eventually, two white light emitting diode (WLED) devices were fabricated, combining the synthesized white emitting phosphors with 365 nm ultraviolet (UV) chips. They exhibited high color rendering indices of 84.7 and 77.0, along with low correlated color temperatures of 5435 K and 5023 K. The Commission Internationale de L'Eclairage (CIE) color coordinates were (0.3349, 0.3975) and (0.3517, 0.4366), respectively. The results pointed to the phosphors' potential suitability for use in the WLED sector.

The Effect of Tub Bathing on the Skin and Bilirubin Levels of Babies Receiving Tunnel and Light-Emitting Diode Phototherapies: A Randomized Controlled Trial.

To investigate the effects of tub bathing on the skin and bilirubin levels of newborns receiving tunnel and light-emitting diode phototherapy. In this randomized controlled trial, hospitalized newborns diagnosed with hyperbilirubinemia treated with a tunnel or light-emitting diode device were randomly assigned to either the experimental (bath) or control (no bath) groups using a computer program. The skin integrity moisture balance of all groups was recorded using the Newborn Skin Condition Score at 6, 12, and 24 hours after phototherapy, and their total serum bilirubin measurements were evaluated. A statistically significant difference was observed in the babies' total serum bilirubin levels; this decrease was the highest in the experimental groups. Further, the skin integrity-moisture balance was higher in the experimental groups than in the control groups; it was highest in the tunnel-experimental group and lowest in the tunnel control group. These results show that bathing is effective in reducing total bilirubin levels. This study adds to the evidence on skin integrity and moisture balance in newborns who were bathed during phototherapy.

Nanoscale interface engineering for enhanced performance in light-emitting-diode devices: ITO/Ag-SRCOOH

In light-emitting diode (LED) devices, the hole-injection layer (HIL) reduces the hole injection barrier (HIB) between the anode and organic layers to obtain favorable conditions for hole transport, which considerably affects device efficiency and performance. However, the fabrication of ultrathin silver (Ag) films for electron and hole transport layers remains challenging. We demonstrated the design of a nanoscale HIL interface with chemisorption-bonded carboxylic acid-terminated alkanethiol self-assembled layers on ultrathin Ag. The device structure consisted of indium tin oxide (ITO)/Ag-mercaptan acid (Ag-SRCOOH)/N, Nj-Di (1-naphthyl)-N,Nj-diphenyl-(1,1-biphenyl)-4,4-diamine (NPB)/tris-(8-hydroxyquinoline) aluminum (Alq3)/ETL(LiF/Al. Notably, a chemical bond peak was not detected between ITO and ultrathin Ag. However, X-ray photoelectron spectroscopy (XPS) measurements confirmed Ag binding to the thiol group of 3-mercaptopropionic acid (MPA) and 11-mercaptoundecanoic acid (MUA) on the Ag island surface, which is evident from -S-Ag- and -RS-Ag- association peaks. Ultraviolet photoelectron spectroscopy analysis results revealed a reduction in the HIB of device from 0.68 to 0.19 eV. Consequently, the luminance and current density, and current density of the AgNP–MPA device increased by 63-fold, 5.8-fold, and 1.1-fold, respectively. Similarly, the AgNP-MUA device exhibited enhanced performance with a 61-fold increase in luminance, 43-fold increase in current density, and a 1.4-fold increase in current efficiency, respectively. The results of this study not only opened novel avenues for future applications, including operation requiring flexibility and transparency of LEDs, but also proposed the optimization of nanoscale interfaces to enhance LED performance.

Supramolecular Sequential Light-Harvesting Systems for Constructing White LED Device and Latent Fingerprint Imaging.

The fabrication of supramolecular light-harvesting systems (LHS) with sequential energy transfer is of significance in utilizing light energy. In this study, we report the non-covalent self-assembly of a sequential LHS by pillar[5]arene-based host-guest interaction in water and its applications in white light-emitting diode (LED) device and latent fingerprint imaging. The host-guest complex WP5 G self-assembles into nanoparticles in water and shows enhanced aggregation-induced emission (AIE) effect. The nanoparticles can be further used to construct sequential LHS with fluorescent dyes 4,7-di(2-thienyl)-benzo[2,1,3]thiadiazole (DBT) and sulforhodamine 101 (SR101). Impressively, the system shows white-light emission when the molar ratio of WP5 G/DBT/SR101 is 1100/2/16. The material can be coated on a LED bulb to achieve white-light emission. In addition, the sequential LHS exhibit multicolor fluorescence including red emission, which have been successfully applied to high-resolution imaging of latent fingerprints. Therefore, we demonstrated a general strategy for the construction of sequential LHS in water based on macrocyclic host-guest interaction and explored its multi-functional applications in white-light LED device and imaging of latent fingerprints, which will promote future development and application of supramolecular LHSs.

Three-Charge (0, -1, -2) Ligand-Based Binuclear and Mononuclear Deep-Red Phosphorescent Iridium Complexes Bearing Benzo[d]oxazole-2-Thiol Ligand.

A new class of three-charge (0, -1, -2) ligand-based binuclear and mononuclear iridium complexes bearing benzo[d]oxazole-2-thiol ligand have been synthesized. Notably, the binuclear complexes (IrIr1 and IrIr2) can be generated at low temperatures by reacting the iridium complex precursors (2a and 2b) with equal amounts of the benzo[d]oxazole-2-thiol ligands, while the corresponding mononuclear complexes (Ir1 and Ir2) are formed at high temperatures. X-ray diffraction analysis shows that the benzo[d]oxazole-2-thiol ligand plays an unusual and interesting bridging role in binuclear complexes and induces rich intermolecular and intramolecular interactions, while in mononuclear complexes, it forms an interesting four-membered ring coordination. More importantly, all complexes experienced efficient deep-red emission in the 628-674 nm range, and the mononuclear complexes have higher luminescent efficiency and longer excited state lifetime than the binuclear complexes. As a result, organic light-emitting diode devices incorporating two mononuclear complexes (Ir1 and Ir2) as guest material of the light-emitting layer can obtain good maximum external quantum efficiency (3.5% and 5.5%) in the deep-red region (629 and 632 nm) with CIE coordinates (0.61, 0.33) and (0.62, 0.34), along with a low turn-on voltage (2.8 V).

Biocompatible Perovskite Nanocrystals with Enhanced Stability for White Light-Emitting Diodes.

Recently emerged lead halide perovskite CsPbX3 (X = Cl, Br, and I) nanocrystals (PNCs) have attracted tremendous attention due to their excellent optical properties. However, the poor water stability, unsatisfactory luminescence efficiency, disappointing lead leakage, and toxicity have restricted their practical applications in photoelectronics and biomedical fields. Herein, a controllable encapsulated strategy is investigated to realize CsPbX3 PNCs/PVP @PMMA composites with superior luminescence properties and excellent biocompatibility. Additionally, the synthesized CsPbBr3 and CsPbBr0.6I2.4 PNCs/PVP@PMMA structures exhibit green and red emissions with a maximal photoluminescence quantum yield (PLQY) of about 70.24% and 98.26%, respectively. These CsPbX3 PNCs/PVP@PMMA structures show high emission efficiency, excellent stability after water storage for 18 months, and low cytotoxicity at the PNC concentration at 500 μg mL-1. Moreover, white light-emitting diode (WLED) devices based on mixtures of CsPbBr3 and CsPbBr0.6I2.4 PNCs/PVP@PMMA perovskite structures are investigated, which exhibit excellent warm-white light emissions at room temperature. A flexible manipulation method is used to fabricate the white light emitters based on these perovskite composites, providing a fantastic platform for fabricating solid-state white light sources and full-color displays.

Simulation of electrical rectification effect in two-dimensional MoSe2/WSe2 lateral heterostructures

Two-dimensional (2D) transition metal dichalcogenides lateral heterostructures exhibit excellent performance in electrics and optics. The electron transport of the heterostructures can be effectively regulated by ingenious design. In this study, we construct a monolayer MoSe2/WSe2 lateral heterostructure, covalently connecting monolayer MoSe2 and monolayer WSe2. Using the Extended Huckel Theory method, we explored current-voltage characteristics under varied conditions, including altering carrier density, atomic replacement and interface angles. Calculations demonstrate a significant electrical rectification ratio (ERR) ranging from 200 to 800. Additionally, Employing Density Functional Theory with non-equilibrium Green’s function method, we investigated electronic properties, attributing the rectification effect to electronic state distribution differences, asymmetric transmission coefficients and band bending of projected local density of states. The expandability of the interfacial energy barrier enhances the rectification effect through adjustments in carrier concentration, atomic replacements and interface size. However, these enhancements introduce challenges such as increased electron-boundary scattering and reduced ambipolarity, resulting in a lower ERR. This study provides valuable theoretical insights for optimizing 2D electronic diode devices, offering avenues for precise control of the rectification effect.

A Simulation Method for Underwater SPAD Depth Imaging Datasets.

In recent years, underwater imaging and vision technologies have received widespread attention, and the removal of the backward-scattering interference caused by impurities in the water has become a long-term research focus for scholars. With the advent of new single-photon imaging devices, single-photon avalanche diode (SPAD) devices, with high sensitivity and a high depth resolution, have become cutting-edge research tools in the field of underwater imaging. However, the high production costs and small array areas of SPAD devices make it very difficult to conduct underwater SPAD imaging experiments. To address this issue, we propose a fast and effective underwater SPAD data simulation method and develop a denoising network for the removal of backward-scattering interference in underwater SPAD images based on deep learning and simulated data. The experimental results show that the distribution difference between the simulated and real underwater SPAD data is very small. Moreover, the algorithm based on deep learning and simulated data for the removal of backward-scattering interference in underwater SPAD images demonstrates effectiveness in terms of both metrics and human observation. The model yields improvements in metrics such as the PSNR, SSIM, and entropy of 5.59 dB, 9.03%, and 0.84, respectively, demonstrating its superior performance.

A novel fluorescent material K3NbOF6: Mn4+ for light-emitting diode devices

A series of K3Nb1-xOF6:xMn4+ fluorescent materials were prepared by the cation exchange method. Phase structure, morphology, emission, excitation spectrum and LED packaging of fluorescent materials were tested. The fluorescent material particles are micron-sized (5 μm–20 μm) and have a micro-rod morphology. It has two absorption bands, with the blue light region (∼468 nm) being stronger than the ultraviolet region (∼370 nm). Under the excitation of 468 nm, it shows good narrowband emission in the red light region, mainly with anti-stokes v6 (∼627 nm), which is caused by the double barrier of the 2Eg→4A2g transition broken by the coupling effect of electron and phonon. The optimum doping concentration was 9.1 %, and as the concentration increased again, the dipole–dipole interaction between Mn4+ resulted in concentration quenching. When the fluorescent material operates at high temperature (150 ℃), the emission intensity drops to 50.2 % of which at room temperature. At high temperature, the electrons absorb a large amount of heat energy, and the non-radiation transition to 4A2g energy level causes the thermal quenching effect. In addition, the sample also showed good water stability, after 1 h of hydrolysis, the luminescence intensity decreased to 85.6 % of the initial value. The use of LED packaging with fluorescent materials and InGaN-YAG:Ce3+ can effectively reduce the color temperature of LED from 6856 K to 3745 K, and enhance the Color index from 61.5 % to 76.8 %. Which has great potential for development in the fields of plant growth and backlight display technology.

Design and Performance Analysis of Photovoltaic Power Generation Light Emitting Diode Device

This research focuses on an independent photovoltaic power generation system with supercapacitor energy storage as the study subject. The model is simplified, and the photovoltaic power generation light emitting diode (LED) device is designed based on the given parameters. This system selects a Boost-type step-up converter for the supercapacitor charging circuit, capable of achieving Maximum Power Point Tracking (MPPT). The supercapacitor discharge circuit employs an LM2596 series regulator to power the rated load LED (12 V, 1 W), providing good linear regulation capability. In designing other hardware components of the device, the characteristics of a photoresistor are utilized to implement an automatic load switch circuit. An efficient single-chip integrated circuit LM2575 series is used as a regulator to convert the voltage across the supercapacitor terminals to +15 V and +5 V. Considering the need to collect the output voltage of the photovoltaic cell array and the voltage across the supercapacitor terminals, a resistor divider method is used to sample these two voltages. The sampling circuit includes a resistor divider circuit and a linear optocoupler isolation circuit. An HNC-25LTS series Hall current sensor is used for current sampling to measure AC, DC, and pulse signals under electrical isolation conditions. The supercapacitor, solar photovoltaic panel, control unit, and the main circuit for supercapacitor charging and discharging have been assembled in the experiment. Connecting the charging and discharging circuit with the photovoltaic panel and LED, the system provides power to the LED during the night. Under varying light intensity and temperature conditions, the photovoltaic output voltage waveform, PWM waveform, and Boost circuit output voltage waveform remain stable when reaching the MPPT point. The output power with added MPPT control at different times is compared. The results indicate that the designed system has effectively achieved the functionality of MPPT for solar energy.

Influence of CoSi Oxidation and Passivation During Silicide Selective Etching on Junction Leakage: Applications to Schottky Diodes Devices

For new analogic microelectronic circuits development based on non-linear devices such as Schottky diodes formed in Si active regions, new Co-silicide integrations are required to reduce junction leakages. To gather targeted device requirements, precise Co silicide/Si interface optimization and a limited silicide formation at the active edges is needed. The selective etching during the “Salicide” process plays a real role in the oxidation and/or passivation of the silicide layer. Here, we propose a systematic study including a very large spectrum of experiments around the main parameters of CoSi selective etching. The main conclusions are (1) diode leakages are directly linked to SiO2 layer thickness formed during the SC1 dispense or by air exposure over the CoSi layer, (2) significant effect of dispense flow on SiO2 formation is measured through X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry characterizations; (3) optimized diode leakages together with contact resistances are then demonstrated for low SC1 delivery flow and long dispense time; and (4) major changes in final CoSi2 layer morphology and silicide/silicon interface are observed by transmission electron microscopy-energy-dispersive X-ray analyses for different selective etching processes, which are potentially explained by enrichment in Co atoms at CoSi/Si during SiO2 overlayer growth.

Ultra-broadband near-infrared emission of Cr3+-containing oxy-fluoride glass-ceramics

Broadband near-infrared (NIR) light sources cover unique optical wavelengths and are valuable in the fields of bioimaging and photodynamic therapy, night vision lighting and security monitoring. NIR phosphor converted light-emitting diode (NIR pc-LED) devices have attractive features such as tunable emission peak, low cost of production, compact in sizes and high luminous efficiency. However, heat accumulation during operation due to poor thermal conductivity of the organic resin used in packaging often causes serious reduction in luminous efficiency and accelerated degradation of the device. In present work, we developed a Cr3+-doped transparent CaF2-based oxy-fluoride glass-ceramic (GC) that showed a broadband emission of 700∼1400 nm under 470 nm excitation. The emission peaked at ∼880 nm, the full-width at half maximum was about ∼297 nm, and the photoluminescence quantum yield reached ∼31.19 %. The emission was derived from the electronic transition of Cr3+ ions from the 4T2(F) to 4A2(F). Through structural analysis and numerical simulation, we showed that during the heat treatment process, Cr3+ ions were enriched into the CaF2 crystal phase and replaced the Ca2+ in the GC host with occupied the center position of the polyhedrons, which provided a weak crystal field and led to NIR emission. We built NIR pc-LED devices using optimized GC and commercial blue LED chips, and we demonstrated the application of this NIR pc-LED in night-vision lighting. Our approaches to prepare simple and stable inorganic NIR luminous materials sealed in bulk in a transparent CaF2-based oxy-fluoride GC and to construct pc-LED devices could provide new concept to the field and have practical implications to applications in related fields.

Temperature Changes in the Pulp Chamber During Orthodontic Bonding Using a High-Power Light-Emitting Diode Device With Two Different Exposure Times and Intensities: An In-Vitro Study.

This study used a high-power light-emitting diode (LED) device to evaluate the effects of two exposure times and intensities on pulp chamber temperature and cooling time during bracket bonding. Sixty upper premolars were used in the sample in this study. These premolars were split into two main groups based on the exposure time and intensity: the first group employed a traditional curing mode (TCG) for 20 seconds with an intensity of 1200 mw/cm2, whereas the second group had a quick curing mode (QCG) for 3 seconds with an intensity of 2500 mw/cm2. The pulp chamber's temperature variations and cooling times were recorded using a thermal imaging camera. The Mann-Whitney U test was used to find differences between the two-group comparison of the pulp chamber's temperature and cooling time. The two groups had statistically significant differences regarding the temperature increase in the pulp chamber and cooling time (p > 0.001). The mean temperature increase in the traditional curing group was 3.52°C, which is greater than that in the quick curing group (i.e., a mean value of 1.28°C). The mean cooling time in the traditional curing group was 38.83 seconds, which is greater than that in the quick curing group (9.97 seconds). Reducing the exposure time to 3 secondsand increasing the intensity to 2500 mw/cm2is considered safer for the pulp chamber during and after the curing process.

Modern methods of treatment of anal stenosis

Objective. To develop and put into practice a new combined method of anal stenosis surgical treatment based on laser plastic surgery of tissues with a diode laser. Assess the effectiveness of the technique based on the analysis of immediate and long-term results, postoperative complications, peculiarities of technical implementation, and features of the quality of patients` life. Materials and methods. The study involved 68 patients with anal stricture after the anal and (or) rectal surgery. All patients underwent laser correction of postoperative scar tissue. According to indications, botulinum toxin was injected into the internal sphincter and (or) PRP autoplasma perarectally. Surgery was performed under intravenous anesthesia with the addition of tumescent anesthesia or local anesthesia. Laser radiation from a diode device with a wavelength of 1.56 microns and a power of 10 W was applied. Results. There are no restrictions on laser correction of anal stenosis regardless of the type and complexity of anal stenosis, it is technically easy to use, minimizes the risk of postoperative complications and relapse of the disease, and has a highly effective treatment result. Conclusions. The technique is characterized by versatility and ease of use, highly effective results, high quality of patients` life, and it can be used routinely on an outpatient basis.

Mn(II)-Based Metal Halide with Near-Unity Quantum Yield for White LEDs and High-Resolution X-ray Imaging.

Metal halides have drawn great interest as luminescent materials and scintillators due to their outstanding optical properties. Exploring new types of phosphors with easy production processes, excellent photophysical properties, high light yields, and environmentally friendly compositions is crucial and quite challenging. Herein, a novel Mn(II)-based metal halide (4-BTP)2MnBr4 was produced using a facile solvent evaporation method, which exhibited a strong green emission peaking at 524 nm from the d-d transition of tetrahedral-coordinated Mn2+ ion and a near-unity quantum yield. The prepared white light-emitting diode device has a wide color gamut of 100.7% NTSC with CIE chromaticity coordinates of (0.32, 0.32). In addition, (4-BTP)2MnBr4 demonstrates excellent characteristics in X-ray scintillation, including a high light yield of 98 000 photons/MeV, a sensitive detection limit of 37.4 nGy/s, excellent resistance to radiation damage, and successful demonstration of X-ray imaging with high resolution at 21.3 lp/mm, revealing the potential for application in diagnostic X-ray medical imaging and industry radiation detection.

Research Progress of Heavy-Metal-Free Quantum Dot Light-Emitting Diodes.

At present, heavy-metal-free quantum dot light-emitting diodes (QLEDs) have shown great potential as a research hotspot in the field of optoelectronic devices. This article reviews the research on heavy-metal-free quantum dot (QD) materials and light-emitting diode (LED) devices. In the first section, we discussed the hazards of heavy-metal-containing quantum dots (QDs), such as environmental pollution and human health risks. Next, the main representatives of heavy-metal-free QDs were introduced, such as InP, ZnE (E=S, Se and Te), CuInS2, Ag2S, and so on. In the next section, we discussed the synthesis methods of heavy-metal-free QDs, including the hot injection (HI) method, the heat up (HU) method, the cation exchange (CE) method, the successful ionic layer adsorption and reaction (SILAR) method, and so on. Finally, important progress in the development of heavy-metal-free QLEDs was summarized in three aspects (QD emitter layer, hole transport layer, and electron transport layer).

Theoretical study of the ϒ2-graphyne p-n junction diode devices

Due to the tunable bandgap of ϒ2-graphyne, there is an expectation that this structure is a favorable candidate for p-n junction diode devices. The characteristic of the pure and hydrogenated ϒ2-graphyne nanoribbon structures is modeled and investigated from the electrostatic point of view. The charge distribution is approximated in one and two dimensions. The space charge region wide, electric field and the potential along with the current density are calculated for different donor and acceptor doping amounts. Our survey includes various simulated hydrogenated and Oxygenated molecular devices with different unit cell numbers, and their density of states, transmission spectrum, and current voltage diagrams were obtained using VNL Quantum wise ATK software. The results indicate the reduction of the depletion region and the creation of new energy levels in the band gap of the system. The interaction and bending effects of these new levels with the intrinsic levels are also observed.

Dicyanovinyl-modified small-molecular monophenyl derivative for dual-channel fluorescence recognition of acid and aliphatic primary amine regulated by intramolecular charge transfer: Synthesis, stimuli-response and LED

The dicyanovinyl-modified monophenyl derivative TSH was synthesized via Vilsmeier and Knoevenagel reactions. TSH has photoluminescence in both solution and solid. It exhibits solvatochromic behavior, shifting from blue to orange due to the intramolecular charge transfer. TSH can undergo a reversible protonation/deprotonation reaction with trifluoroacetic acid/triethylamine, leading to acidochromism. Additionally, TSH reacts with aliphatic primary amines, causing fluorescence changes from yellow to blue for specific recognition of aliphatic primary amines. The fluorescence changes resulting from the recognition of acid and aliphatic primary amines are related to the change of intramolecular charge transfer. The two recognition phenomena are different, allowing for the design of various fluorescent anti-counterfeiting measures. Moreover, TSH can be utilized in fabricating yellow light-emitting diode device with high color purity (91 %).