Stimulated emission and lasing of GaN-based laser diodes(LDs)were reported at 1995[1]and 1996[2],right after the breakthrough of p-type doping[3−5],material quality[6]and the invention of high-brightness GaN-based LED...Stimulated emission and lasing of GaN-based laser diodes(LDs)were reported at 1995[1]and 1996[2],right after the breakthrough of p-type doping[3−5],material quality[6]and the invention of high-brightness GaN-based LEDs[7,8].However,it took much longer time for GaN-based LDs to achieve high power,high wall plug efficiency,and long lifetime.Until 2019,Nichia reported blue LDs with these performances[9],which open wide applications with GaN-based blue LDs.展开更多
Power grid is an indispensable infrastructure in modern society,in order to ensure the normal operation of the grid,online non-contact monitoring of high-voltage lines is essential.In this work,a‘capacitor-laser diod...Power grid is an indispensable infrastructure in modern society,in order to ensure the normal operation of the grid,online non-contact monitoring of high-voltage lines is essential.In this work,a‘capacitor-laser diode(LD)-capacitor’structure,namely,laser diode in capacitors(LDIC),that can be used for non-contact monitoring of high-voltage(HV)line status by directly transferring the status information of the HV line to modulated laser pulses is proposed.The proposed LDIC can accurately extract the real-time voltage changes on the HV line with an accuracy level of 0.959%.Because the LDIC is sensitive to high-frequency electromagnetic field,the LDIC is successfully utilised to detect the external electromagnetic interference(EMI)to obtain the intensity and frequency of the external EMI.Additionally,the amplitude and frequency of the HV line vibration can be accurately monitored by using the LDIC.For the third-order curve fitting of vibration amplitude,the average error is only 0.00867,and the average error of linear fitting of vibration frequency is as low as 0.00655.This work provides a novel approach for the online monitoring of the HV line status and a new supplement for the development of power grid technology.展开更多
Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yiel...Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yield(PLQY).Despite significant advancements in their performance,challenges such as defects and ion migration still hinder their long-term stability and operational efficiency.To address these issues,various optimization strategies,including ligand engineering,interface passivation,and self-assembly strategy,are being actively researched.This review focuses on the synthesis methods,challenges and optimization of perovskite quantum dots,which are critical for the commercialization and large-scale production of high-performance and stable Pe-QLEDs.展开更多
Rectifying circuit,as a crucial component for converting alternating current into direct current,plays a pivotal role in energy harvesting microsystems.Traditional silicon-based or germanium-based rectifier diodes hin...Rectifying circuit,as a crucial component for converting alternating current into direct current,plays a pivotal role in energy harvesting microsystems.Traditional silicon-based or germanium-based rectifier diodes hinder system integration due to their specific manufacturing processes.Conversely,metal oxide diodes,with their simple fabrication techniques,offer advantages for system integration.The oxygen vacancy defect of oxide semiconductor will greatly affect the electrical performance of the device,so the performance of the diode can be effectively controlled by adjusting the oxygen vacancy concentration.This study centers on optimizing the performance of diodes by modulating the oxygen vacancy concentration within InGaZnO films through control of oxygen flows during the sputtering process.Experimental results demonstrate that the diode exhibits a forward current density of 43.82 A·cm^(−2),with a rectification ratio of 6.94×10^(4),efficiently rectifying input sine signals with 1 kHz frequency and 5 V magnitude.These results demonstrate its potential in energy conversion and management.By adjusting the oxygen vacancy,a methodology is provided for optimizing the performance of rectifying diodes.展开更多
The quantum confinement effect fundamentally alters the optical and electronic properties of quantum dots(QDs),making them versatile building blocks for next-generation light-emitting diodes(LEDs).This study investiga...The quantum confinement effect fundamentally alters the optical and electronic properties of quantum dots(QDs),making them versatile building blocks for next-generation light-emitting diodes(LEDs).This study investigates how quantum confinement governs the charge transport,exciton dynamics,and emission efficiency in QD-LEDs,using CsPbI_(3) QDs as a model system.By systematically varying QD sizes,we reveal size-dependent trade-offs in LED performance,such as enhanced efficiency for smaller QDs but increased brightness and stability for larger QDs under high current densities.Our findings offer critical insights into the design of high-performance QD-LEDs,paving the way for scalable and energy-efficient optoelectronic devices.展开更多
There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresse...There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresses carrier leakage by inserting n-Ga_(0.55)In_(0.45)P and p-GaAs_(0.6)P_(0.4) between barriers and waveguide layers,respectively,to modulate the energy band structure and to increase the height of barrier.The results show that the leakage current density reduces by 87.71%,compared to traditional structure.The nonradiative recombination current density of novel structure reduces to 37.411 A/cm^(2),and the output power reaches 12.80 W with wall-plug efficiency of 78.24%at an injection current density 5 A/cm^(2) at room temperature.In addition,the temperature drift coefficient of center wavelength is 0.206 nm/℃at the temperature range from 5℃to 65℃,and the slope of fitted straight line of threshold current with temperature variation is 0.00113.The novel epitaxial structure provides a theoretical basis for achieving high-power laser diode.展开更多
As an inherent current-driven device,the luminous intensity of a single-unit perovskite light-emitting diode is directly proportional to the current density.However,this relationship can lead to a deterioration in the...As an inherent current-driven device,the luminous intensity of a single-unit perovskite light-emitting diode is directly proportional to the current density.However,this relationship can lead to a deterioration in the operational lifetime of the device at high current densities.In contrast,a tandem device structure,not only requires less current to achieve equivalent brightness compared to a single-unit device but also nearly achieves the combined efficiencies of each light-emitting unit.Herein,we present recommendations and protocols designed to facilitate the fabrication of all-tandem perovskite light-emitting diode,with the aim of benefiting both the research and industrial communities.展开更多
We investigate the possible Josephson diode effect(JDE)in a two-dimensional(2D)nonmagnetic planar s-wave superconductor junction,which is constructed on a spin-collinear d-wave altermagnet(AM)material in the presence ...We investigate the possible Josephson diode effect(JDE)in a two-dimensional(2D)nonmagnetic planar s-wave superconductor junction,which is constructed on a spin-collinear d-wave altermagnet(AM)material in the presence of Rashba spin-orbit interaction.It is demonstrated that the JDE is critically dependent on the crystalline axis of the AM relative to the current direction.The d_(x^(2)-y^(2))magnetization symmetry can support a JDE whereas the dxy symmetry does not facilitate it.The JDE efficiency can reach up to 40%and can be adjusted by an additional asymmetric gate voltage applied to the non-superconducting region of the junction,including control of its polarity.Our findings provide an electrical means to control the JDE within a non-magnetic AM-based superconducting junction.展开更多
Promoting the high penetration of renewable energies like photovoltaic(PV)systems has become an urgent issue for expanding modern power grids and has accomplished several challenges compared to existing distribution g...Promoting the high penetration of renewable energies like photovoltaic(PV)systems has become an urgent issue for expanding modern power grids and has accomplished several challenges compared to existing distribution grids.This study measures the effectiveness of the Puma optimizer(PO)algorithm in parameter estimation of PSC(perovskite solar cells)dynamic models with hysteresis consideration considering the electric field effects on operation.The models used in this study will incorporate hysteresis effects to capture the time-dependent behavior of PSCs accurately.The PO optimizes the proposed modified triple diode model(TDM)with a variable voltage capacitor and resistances(VVCARs)considering the hysteresis behavior.The suggested PO algorithm contrasts with other wellknown optimizers from the literature to demonstrate its superiority.The results emphasize that the PO realizes a lower RMSE(Root mean square errors),which proves its capability and efficacy in parameter extraction for the models.The statistical results emphasize the efficiency and supremacy of the proposed PO compared to the other well-known competing optimizers.The convergence rates show good,fast,and stable convergence rates with lower RMSE via PO compared to the other five competitive optimizers.Moreover,the lowermean realized via the PO optimizer is illustrated by the box plot for all optimizers.展开更多
Moisture-enabled electricity generation(MEG)has emerged as a promising sustainable energy harvesting technology,comparable to photovoltaics,thermoelectrics,and triboelectrics[1].MEGs generate electricity by converting...Moisture-enabled electricity generation(MEG)has emerged as a promising sustainable energy harvesting technology,comparable to photovoltaics,thermoelectrics,and triboelectrics[1].MEGs generate electricity by converting the chemical potential of moisture into electric energy through interactions with hygroscopic materials and nanostructured interfaces.Unlike solar or thermal harvesters,MEGs operate continuously by utilizing ubiquitous atmospheric moisture,granting them unique spatial and temporal adaptability.Despite nearly a decade of progress and the exploration of diverse material systems for MEG,the overall output power remains significantly limited due to inherently low charge carrier concentrations and restricted ion diffusion fluxes[2].As a result,standalone MEG devices often deliver low and unstable output,limiting practical applications.To enhance performance and versatility,recent efforts have explored hybridization of MEG with other ambient energy sources such as triboelectric or thermoelectric effects.展开更多
Eco-friendly quantum-dot light-emitting diodes(QLEDs),which employ colloidal quantum dots(QDs)such as InP,and ZnSe,stand out due to their low toxicity,color purity,and high efficiency.Currently,significant advancement...Eco-friendly quantum-dot light-emitting diodes(QLEDs),which employ colloidal quantum dots(QDs)such as InP,and ZnSe,stand out due to their low toxicity,color purity,and high efficiency.Currently,significant advancements have been made in the performance of cadmium-free QLEDs.However,several challenges persist in the industrialization of ecofriendly QLED displays.For instance,(1)the poor performance,characterized by low photoluminescence quantum yield(PLQY),unstable ligand,and charge imbalance,cannot be effectively addressed with a solitary strategy;(2)the degradation mechanism,involving emission quenching,morphological inhomogeneity,and field-enhanced electron delocalization remains unclear;(3)the lack of techniques for color patterning,such as optical lithography and transfer printing.Herein,we undertake a specific review of all technological breakthroughs that endeavor to tackle the above challenges associated with cadmium-free QLED displays.We begin by reviewing the evolution,architecture,and operational characteristics of eco-friendly QLEDs,highlighting the photoelectric properties of QDs,carrier transport layer stability,and device lifetime.Subsequently,we focus our attention not only on the latest insights into device degradation mechanisms,particularly,but also on the remarkable technological progress in color patterning techniques.To conclude,we provide a synthesis of the promising prospects,current challenges,potential solutions,and emerging research trends for QLED displays.展开更多
Carbon dots(CDs),due to their low cost,high stability,and high luminous efficiency,have emerged as an excellent material for the emissive layer in next-generation electroluminescent light-emitting diodes(ELEDs).Howeve...Carbon dots(CDs),due to their low cost,high stability,and high luminous efficiency,have emerged as an excellent material for the emissive layer in next-generation electroluminescent light-emitting diodes(ELEDs).However,improving the efficiency of fluorescent CDs-based ELEDs remains challenging,primarily because it is difficult to utilize triplet excitons in the electroluminescence process.Therefore,enhancing the exciton utilization efficiency of CDs during electroluminescence is crucial.Based on this,we exploited the characteristic large exciton binding energy commonly found in CDs to develop exciton-emitting CDs.These CDs facilitate the radiative recombination of excitons during electroluminescence,thereby improving the electroluminescent efficiency.By rationally selecting precursors,we developed high quantum efficiency CDs and subsequently constructed CDs-based ELEDs.The blue-light device exhibited an external quantum efficiency of over 4%.This study introduces a novel design concept for CDs,providing a new strategy for developing high-performance blue ELEDs based on CDs.展开更多
GaN diodes for high energy(64.8 MeV)proton detection were fabricated and investigated.A comparison of the performance of GaN diodes with different structures is presented,with a focus on sapphire and on GaN substrates...GaN diodes for high energy(64.8 MeV)proton detection were fabricated and investigated.A comparison of the performance of GaN diodes with different structures is presented,with a focus on sapphire and on GaN substrates,Schottky and pin diodes,and different active layer thicknesses.Pin diodes fabricated on a sapphire substrate are the best choice for a GaN proton detector working at 0 V bias.They are sensitive(minimum detectable proton beam<1 pA/cm^(2)),linear as a function of proton current and fast(<1 s).High proton current sensitivity and high spatial resolution of GaN diodes can be exploited in the future for proton imaging of patients in proton therapy.展开更多
Background Plant tissue culture has emerged as a tool for improving cotton propagation and genetics,but recalcitrance nature of cotton makes it difficult to develop in vitro regeneration.Cotton’s recalcitrance is inf...Background Plant tissue culture has emerged as a tool for improving cotton propagation and genetics,but recalcitrance nature of cotton makes it difficult to develop in vitro regeneration.Cotton’s recalcitrance is influenced by genotype,explant type,and environmental conditions.To overcome these issues,this study uses different machine learning-based predictive models by employing multiple input factors.Cotyledonary node explants of two commercial cotton cultivars(STN-468 and GSN-12)were isolated from 7–8 days old seedlings,preconditioned with 5,10,and 20 mg·L^(-1) kinetin(KIN)for 10 days.Thereafter,explants were postconditioned on full Murashige and Skoog(MS),1/2MS,1/4MS,and full MS+0.05 mg·L^(-1) KIN,cultured in growth room enlightened with red and blue light-emitting diodes(LED)combination.Statistical analysis(analysis of variance,regression analysis)was employed to assess the impact of different treatments on shoot regeneration,with artificial intelligence(AI)models used for confirming the findings.Results GSN-12 exhibited superior shoot regeneration potential compared with STN-468,with an average of 4.99 shoots per explant versus 3.97.Optimal results were achieved with 5 mg·L^(-1) KIN preconditioning,1/4MS postconditioning,and 80%red LED,with maximum of 7.75 shoot count for GSN-12 under these conditions;while STN-468 reached 6.00 shoots under the conditions of 10 mg·L^(-1) KIN preconditioning,MS with 0.05 mg·L^(-1) KIN(postconditioning)and 75.0%red LED.Rooting was successfully achieved with naphthalene acetic acid and activated charcoal.Additionally,three different powerful AI-based models,namely,extreme gradient boost(XGBoost),random forest(RF),and the artificial neural network-based multilayer perceptron(MLP)regression models validated the findings.Conclusion GSN-12 outperformed STN-468 with optimal results from 5 mg·L^(-1) KIN+1/4MS+80%red LED.Application of machine learning-based prediction models to optimize cotton tissue culture protocols for shoot regeneration is helpful to improve cotton regeneration efficiency.展开更多
The packaging quality of coaxial laser diodes(CLDs)plays a pivotal role in determining their optical performance and long-term reliability.As the core packaging process,high-precision laser welding requires precise co...The packaging quality of coaxial laser diodes(CLDs)plays a pivotal role in determining their optical performance and long-term reliability.As the core packaging process,high-precision laser welding requires precise control of process parameters to suppress optical power loss.However,the complex nonlinear relationship between welding parameters and optical power loss renders traditional trial-and-error methods inefficient and imprecise.To address this challenge,a physics-informed(PI)and data-driven collaboration approach for welding parameter optimization is proposed.First,thermal-fluid-solid coupling finite element method(FEM)was employed to quantify the sensitivity of welding parameters to physical characteristics,including residual stress.This analysis facilitated the identification of critical factors contributing to optical power loss.Subsequently,a Gaussian process regression(GPR)model incorporating finite element simulation prior knowledge was constructed based on the selected features.By introducing physics-informed kernel(PIK)functions,stress distribution patterns were embedded into the prediction model,achieving high-precision optical power loss prediction.Finally,a Bayesian optimization(BO)algorithm with an adaptive sampling strategy was implemented for efficient parameter space exploration.Experimental results demonstrate that the proposedmethod effectively establishes explicit physical correlations between welding parameters and optical power loss.The optimized welding parameters reduced optical power loss by 34.1%,providing theoretical guidance and technical support for reliable CLD packaging.展开更多
Perovskite light-emitting diodes(PeLEDs)have shown outstanding potential in next-generation lighting and display owing to the advantages of broad spectral tunability,excellent color purity,high photoluminescence quant...Perovskite light-emitting diodes(PeLEDs)have shown outstanding potential in next-generation lighting and display owing to the advantages of broad spectral tunability,excellent color purity,high photoluminescence quantum yields(PLQYs),and low processing cost.Device efficiency and stability are crucial indicators to evaluate whether a PeLED can meet commercial application requirements.In this review,we first discuss strategies for achieving high external quantum efficiencies(EQEs),including controlling charge injection and balance,enhancing radiative recombination,and improving light outcoupling efficiency.Next,we review recent advances in operational stability of PeLEDs and emphasize the mechanisms of degradation in PeLEDs,including ion migration,structural transformations,chemical interactions,and thermal degradation.Through detailed analysis and discussion,this review aims to facilitate progress and innovation in highly efficient and stable PeLEDs,which have significant promise for display and solid-state lighting technologies,as well as other emerging applications.展开更多
A binary-mixed electron transport layer(ETL)has been reported for constructing solution-processable near-infrared organic light-emitting diodes(NIR OLEDs).Relative to the single-component ETL,the binarymixed ETL compo...A binary-mixed electron transport layer(ETL)has been reported for constructing solution-processable near-infrared organic light-emitting diodes(NIR OLEDs).Relative to the single-component ETL,the binarymixed ETL composed of PDINN:TPBi can enhance the carrier transport capacity,reduce device impedance,and weaken fiuorescence quenching of the emitting layer.By carefully selecting an appropriate luminescent material Y5(a nonfullerene electron acceptor in organic solar cells)and precisely fine-tuning the molecular aggregation in active layer using a mixed solvent,the morphology is optimized and luminescence performance is enhanced,resulting in efficient NIR OLEDs with an emission peak at 890 nm.The experiment showcases a Y5-based near-infrared OLED with a maximum radiance of 34.9 W sr^(-1)m^(-2)and a maximum external quantum efficiency of 0.50%,which is among the highest values reported for nondoped fiuorescent NIR OLEDs with an emission peak over 850 nm.展开更多
Triphenylamine(TPA)is the most promising donor fragment for the construction of long-wavelength thermally activated delayed fluorescence(TADF)emitters owing to its suitable dihedral angle that could enhance radiative ...Triphenylamine(TPA)is the most promising donor fragment for the construction of long-wavelength thermally activated delayed fluorescence(TADF)emitters owing to its suitable dihedral angle that could enhance radiative decay to compete with the serious non-radiative decay.However,the moderate electron-donating capacity of TPA seriously limits the selection of acceptor for constructing longwavelength TADF emitters with narrow bandgaps.To address this issue,in this work,the peripheral benzene of TPA was replaced with 1,4-benzodioxane and anisole to obtain two new electrondonating units N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-N-phenyl-2,3-dihydrobenzo[b][1,4]dioxin-6-amine(TPADBO,−5.02 eV)and 4-methoxy-N-(4-methoxyphenyl)-N-phenylaniline(TPAMO,−5.00 eV),which possess much shallower highest occupied molecule orbital(HOMO)energy levels than the prototype TPA(−5.33 eV).Based on TPA and the modified TPA donor fragments,three TADF emitters were designed and synthesized,namely Py-TPA,Py-TPADBO and Py-TPAMO,with the same acceptor fragment 12-(2,6-diisopropylphenyl)pyrido[2′,3′:5,6]pyrazino[2,3-f][1,10]phenanthroline(Py).Among them,Py-TPAMO exhibits the highest photoluminescence quantum yield of 78.4%and the smallest singlet-triplet energy gap,which is because the introduction of anisole does not cause significant molecule deformation for the excited Py-TPAMO.And Py-TPAMO-based OLEDs successfully realize a maximum external quantum efficiency of 25.5%with the emission peak at 605 nm.This work provides a series of candidate of donor fragments for the development of efficient long-wavelength TADF emitters.展开更多
Colloidal quantum dots(CQDs)are highly regarded for their outstanding photovoltaic characteristics,including excellent color purity,stability,high photoluminescence quantum yield(PLQY),narrow emission spectra,and ease...Colloidal quantum dots(CQDs)are highly regarded for their outstanding photovoltaic characteristics,including excellent color purity,stability,high photoluminescence quantum yield(PLQY),narrow emission spectra,and ease of solution processing.Despite significant progress in quantum dot light-emitting diodes(QLEDs)technology since its inception in 1994,blue QLEDs still fall short in efficiency and lifespan compared to red and green versions.The toxicity concerns associated with Cd/Pb-based quantum dots(QDs)have spurred the development of heavy-metal-free alternatives,such as groupⅡ−Ⅵ(e.g.,ZnSe-based QDs),groupⅢ−Ⅴ(e.g.,InP,GaN QDs),and carbon dots(CDs).In this review,we discuss the key properties and development history of quantum dots(QDs),various synthesis approaches,the role of surface ligands,and important considerations in developing core/shell(C/S)structured QDs.Additionally,we provide an outlook on the challenges and future directions for blue QLEDs.展开更多
A red-emitting phosphor Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) with partial Al^(3+)/P^(5+) substitution on Si^(4+) was synthesized via a simple solid-state method,and the effects of the introduction of the M^(3+/5+)(M=Al,P)...A red-emitting phosphor Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) with partial Al^(3+)/P^(5+) substitution on Si^(4+) was synthesized via a simple solid-state method,and the effects of the introduction of the M^(3+/5+)(M=Al,P)ions on the crystal structure and photoluminescence performance of Ca_(2.91)Si_(2−x)M_(x)O_(7):0.09Eu^(3+) phosphors were investigated.The X-ray diffraction(XRD),energy-dispersive X-ray spectroscopy(EDS),and X-ray photoelectron spectroscopy(XPS)results revealed that the structure of Ca_(3)Si_(2)O_(7) remained the same after the introduction of Al^(3+) and P^(5+) ions.The characteristic emission of Eu^(3+)-doped Ca_(3)Si_(2−x)M_(x)O_(7) phosphors exhibited two main peaks at 617 nm(red)and 593 nm(orange)under excitation at 394 nm,which originated from the^(5)D_(0)→^(7)F_(2)and^(5)D_(0)→^(7)F_(1) electron transitions of Eu^(3+) ions.After the partial substitution of Al^(3+) and P^(5+),the red emission intensities of the Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) phosphors were significantly enhanced by 1.88-and 1.42-fold,respectively,which is attributed to the crystal-field effect around Eu^(3+).Meanwhile,the luminescence intensities of the Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+) and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) phosphors at 210℃ were 79.36%and 77.53%of those at 30°C,respectively,indicating their excellent thermal stability.Moreover,the as-prepared Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+)and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) red-emitting phosphors were combined with a near-ultraviolet chip of 395 nm to fabricate red-light-emitting diode(LED)and white(w)-LED devices with excellent chromaticity features.In summary,Al^(3+)/P^(5+)-substituted Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) can serve as red-emitting phosphors for applications in w-LEDs.展开更多
基金supported by the Natural Science Foundation of Jiangsu Province(Grant.BK20232042).
文摘Stimulated emission and lasing of GaN-based laser diodes(LDs)were reported at 1995[1]and 1996[2],right after the breakthrough of p-type doping[3−5],material quality[6]and the invention of high-brightness GaN-based LEDs[7,8].However,it took much longer time for GaN-based LDs to achieve high power,high wall plug efficiency,and long lifetime.Until 2019,Nichia reported blue LDs with these performances[9],which open wide applications with GaN-based blue LDs.
基金supported by National Key R&D Program of China under Grant No.2021YFB3600400Mindu Innovation Laboratory Project under Grant No.2020ZZ113.
文摘Power grid is an indispensable infrastructure in modern society,in order to ensure the normal operation of the grid,online non-contact monitoring of high-voltage lines is essential.In this work,a‘capacitor-laser diode(LD)-capacitor’structure,namely,laser diode in capacitors(LDIC),that can be used for non-contact monitoring of high-voltage(HV)line status by directly transferring the status information of the HV line to modulated laser pulses is proposed.The proposed LDIC can accurately extract the real-time voltage changes on the HV line with an accuracy level of 0.959%.Because the LDIC is sensitive to high-frequency electromagnetic field,the LDIC is successfully utilised to detect the external electromagnetic interference(EMI)to obtain the intensity and frequency of the external EMI.Additionally,the amplitude and frequency of the HV line vibration can be accurately monitored by using the LDIC.For the third-order curve fitting of vibration amplitude,the average error is only 0.00867,and the average error of linear fitting of vibration frequency is as low as 0.00655.This work provides a novel approach for the online monitoring of the HV line status and a new supplement for the development of power grid technology.
文摘Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yield(PLQY).Despite significant advancements in their performance,challenges such as defects and ion migration still hinder their long-term stability and operational efficiency.To address these issues,various optimization strategies,including ligand engineering,interface passivation,and self-assembly strategy,are being actively researched.This review focuses on the synthesis methods,challenges and optimization of perovskite quantum dots,which are critical for the commercialization and large-scale production of high-performance and stable Pe-QLEDs.
文摘Rectifying circuit,as a crucial component for converting alternating current into direct current,plays a pivotal role in energy harvesting microsystems.Traditional silicon-based or germanium-based rectifier diodes hinder system integration due to their specific manufacturing processes.Conversely,metal oxide diodes,with their simple fabrication techniques,offer advantages for system integration.The oxygen vacancy defect of oxide semiconductor will greatly affect the electrical performance of the device,so the performance of the diode can be effectively controlled by adjusting the oxygen vacancy concentration.This study centers on optimizing the performance of diodes by modulating the oxygen vacancy concentration within InGaZnO films through control of oxygen flows during the sputtering process.Experimental results demonstrate that the diode exhibits a forward current density of 43.82 A·cm^(−2),with a rectification ratio of 6.94×10^(4),efficiently rectifying input sine signals with 1 kHz frequency and 5 V magnitude.These results demonstrate its potential in energy conversion and management.By adjusting the oxygen vacancy,a methodology is provided for optimizing the performance of rectifying diodes.
基金support from the National Key Research and Development Program of China(2024YFA1207700)National Natural Science Foundation of China(52072141,52102170).
文摘The quantum confinement effect fundamentally alters the optical and electronic properties of quantum dots(QDs),making them versatile building blocks for next-generation light-emitting diodes(LEDs).This study investigates how quantum confinement governs the charge transport,exciton dynamics,and emission efficiency in QD-LEDs,using CsPbI_(3) QDs as a model system.By systematically varying QD sizes,we reveal size-dependent trade-offs in LED performance,such as enhanced efficiency for smaller QDs but increased brightness and stability for larger QDs under high current densities.Our findings offer critical insights into the design of high-performance QD-LEDs,paving the way for scalable and energy-efficient optoelectronic devices.
文摘There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresses carrier leakage by inserting n-Ga_(0.55)In_(0.45)P and p-GaAs_(0.6)P_(0.4) between barriers and waveguide layers,respectively,to modulate the energy band structure and to increase the height of barrier.The results show that the leakage current density reduces by 87.71%,compared to traditional structure.The nonradiative recombination current density of novel structure reduces to 37.411 A/cm^(2),and the output power reaches 12.80 W with wall-plug efficiency of 78.24%at an injection current density 5 A/cm^(2) at room temperature.In addition,the temperature drift coefficient of center wavelength is 0.206 nm/℃at the temperature range from 5℃to 65℃,and the slope of fitted straight line of threshold current with temperature variation is 0.00113.The novel epitaxial structure provides a theoretical basis for achieving high-power laser diode.
基金support by the National Key Research and Development Program of China(No.2022YFA1204800)the National Natural Science Foundation of China(No.U21A2078)the Scientific Research Funds of Huaqiao University(No.23BS109).
文摘As an inherent current-driven device,the luminous intensity of a single-unit perovskite light-emitting diode is directly proportional to the current density.However,this relationship can lead to a deterioration in the operational lifetime of the device at high current densities.In contrast,a tandem device structure,not only requires less current to achieve equivalent brightness compared to a single-unit device but also nearly achieves the combined efficiencies of each light-emitting unit.Herein,we present recommendations and protocols designed to facilitate the fabrication of all-tandem perovskite light-emitting diode,with the aim of benefiting both the research and industrial communities.
基金supported by the National Natural Science Foundation of China(Grant No.12174051)the Fundamental Research Funds for Central Universities。
文摘We investigate the possible Josephson diode effect(JDE)in a two-dimensional(2D)nonmagnetic planar s-wave superconductor junction,which is constructed on a spin-collinear d-wave altermagnet(AM)material in the presence of Rashba spin-orbit interaction.It is demonstrated that the JDE is critically dependent on the crystalline axis of the AM relative to the current direction.The d_(x^(2)-y^(2))magnetization symmetry can support a JDE whereas the dxy symmetry does not facilitate it.The JDE efficiency can reach up to 40%and can be adjusted by an additional asymmetric gate voltage applied to the non-superconducting region of the junction,including control of its polarity.Our findings provide an electrical means to control the JDE within a non-magnetic AM-based superconducting junction.
基金supported via funding from Prince Sattam Bin Abdulaziz University project number(PSAU/2025/R/1446).
文摘Promoting the high penetration of renewable energies like photovoltaic(PV)systems has become an urgent issue for expanding modern power grids and has accomplished several challenges compared to existing distribution grids.This study measures the effectiveness of the Puma optimizer(PO)algorithm in parameter estimation of PSC(perovskite solar cells)dynamic models with hysteresis consideration considering the electric field effects on operation.The models used in this study will incorporate hysteresis effects to capture the time-dependent behavior of PSCs accurately.The PO optimizes the proposed modified triple diode model(TDM)with a variable voltage capacitor and resistances(VVCARs)considering the hysteresis behavior.The suggested PO algorithm contrasts with other wellknown optimizers from the literature to demonstrate its superiority.The results emphasize that the PO realizes a lower RMSE(Root mean square errors),which proves its capability and efficacy in parameter extraction for the models.The statistical results emphasize the efficiency and supremacy of the proposed PO compared to the other well-known competing optimizers.The convergence rates show good,fast,and stable convergence rates with lower RMSE via PO compared to the other five competitive optimizers.Moreover,the lowermean realized via the PO optimizer is illustrated by the box plot for all optimizers.
基金the financial support of the National Natural Science Foundation of China(No.22205165).
文摘Moisture-enabled electricity generation(MEG)has emerged as a promising sustainable energy harvesting technology,comparable to photovoltaics,thermoelectrics,and triboelectrics[1].MEGs generate electricity by converting the chemical potential of moisture into electric energy through interactions with hygroscopic materials and nanostructured interfaces.Unlike solar or thermal harvesters,MEGs operate continuously by utilizing ubiquitous atmospheric moisture,granting them unique spatial and temporal adaptability.Despite nearly a decade of progress and the exploration of diverse material systems for MEG,the overall output power remains significantly limited due to inherently low charge carrier concentrations and restricted ion diffusion fluxes[2].As a result,standalone MEG devices often deliver low and unstable output,limiting practical applications.To enhance performance and versatility,recent efforts have explored hybridization of MEG with other ambient energy sources such as triboelectric or thermoelectric effects.
基金supported by the Research Projects of Department of Education of Guangdong Province-024CJPT002Special Project of Guangdong Provincial Department of Education in Key Areas (No. 6021210075K)Shenzhen Polytechnic University Research Fund. (No. 6024310006K)
文摘Eco-friendly quantum-dot light-emitting diodes(QLEDs),which employ colloidal quantum dots(QDs)such as InP,and ZnSe,stand out due to their low toxicity,color purity,and high efficiency.Currently,significant advancements have been made in the performance of cadmium-free QLEDs.However,several challenges persist in the industrialization of ecofriendly QLED displays.For instance,(1)the poor performance,characterized by low photoluminescence quantum yield(PLQY),unstable ligand,and charge imbalance,cannot be effectively addressed with a solitary strategy;(2)the degradation mechanism,involving emission quenching,morphological inhomogeneity,and field-enhanced electron delocalization remains unclear;(3)the lack of techniques for color patterning,such as optical lithography and transfer printing.Herein,we undertake a specific review of all technological breakthroughs that endeavor to tackle the above challenges associated with cadmium-free QLED displays.We begin by reviewing the evolution,architecture,and operational characteristics of eco-friendly QLEDs,highlighting the photoelectric properties of QDs,carrier transport layer stability,and device lifetime.Subsequently,we focus our attention not only on the latest insights into device degradation mechanisms,particularly,but also on the remarkable technological progress in color patterning techniques.To conclude,we provide a synthesis of the promising prospects,current challenges,potential solutions,and emerging research trends for QLED displays.
基金supported by the National Natural Science Foundation of China(Nos.22205058,22105064,52122308)the Funding Plan of Key Scientific Research Projects in Colleges and Universities of Henan Province(No.23A150001)+2 种基金Doctoral Scientific Research Start-up Foundation from Henan University of Technology(No.2021BS024)the Project of Youth Backbone Teachers of Henan University of Technology(No.21421250)the Innovative Funds Plan of Henan University of Technology(No.2022ZKCJ01)。
文摘Carbon dots(CDs),due to their low cost,high stability,and high luminous efficiency,have emerged as an excellent material for the emissive layer in next-generation electroluminescent light-emitting diodes(ELEDs).However,improving the efficiency of fluorescent CDs-based ELEDs remains challenging,primarily because it is difficult to utilize triplet excitons in the electroluminescence process.Therefore,enhancing the exciton utilization efficiency of CDs during electroluminescence is crucial.Based on this,we exploited the characteristic large exciton binding energy commonly found in CDs to develop exciton-emitting CDs.These CDs facilitate the radiative recombination of excitons during electroluminescence,thereby improving the electroluminescent efficiency.By rationally selecting precursors,we developed high quantum efficiency CDs and subsequently constructed CDs-based ELEDs.The blue-light device exhibited an external quantum efficiency of over 4%.This study introduces a novel design concept for CDs,providing a new strategy for developing high-performance blue ELEDs based on CDs.
基金support from MATRIX(ANR-22-CE92-0047)with financial support from ITMI Cancer of Aviesan within the framework of the 2021−2030 Cancer Control Strategy,on funds administrated by INSERM through the project NECTAR.Matilde Siviero acknowledges funding from the French−German University/Saarbrücken(contract CDOC-06-2022).
文摘GaN diodes for high energy(64.8 MeV)proton detection were fabricated and investigated.A comparison of the performance of GaN diodes with different structures is presented,with a focus on sapphire and on GaN substrates,Schottky and pin diodes,and different active layer thicknesses.Pin diodes fabricated on a sapphire substrate are the best choice for a GaN proton detector working at 0 V bias.They are sensitive(minimum detectable proton beam<1 pA/cm^(2)),linear as a function of proton current and fast(<1 s).High proton current sensitivity and high spatial resolution of GaN diodes can be exploited in the future for proton imaging of patients in proton therapy.
文摘Background Plant tissue culture has emerged as a tool for improving cotton propagation and genetics,but recalcitrance nature of cotton makes it difficult to develop in vitro regeneration.Cotton’s recalcitrance is influenced by genotype,explant type,and environmental conditions.To overcome these issues,this study uses different machine learning-based predictive models by employing multiple input factors.Cotyledonary node explants of two commercial cotton cultivars(STN-468 and GSN-12)were isolated from 7–8 days old seedlings,preconditioned with 5,10,and 20 mg·L^(-1) kinetin(KIN)for 10 days.Thereafter,explants were postconditioned on full Murashige and Skoog(MS),1/2MS,1/4MS,and full MS+0.05 mg·L^(-1) KIN,cultured in growth room enlightened with red and blue light-emitting diodes(LED)combination.Statistical analysis(analysis of variance,regression analysis)was employed to assess the impact of different treatments on shoot regeneration,with artificial intelligence(AI)models used for confirming the findings.Results GSN-12 exhibited superior shoot regeneration potential compared with STN-468,with an average of 4.99 shoots per explant versus 3.97.Optimal results were achieved with 5 mg·L^(-1) KIN preconditioning,1/4MS postconditioning,and 80%red LED,with maximum of 7.75 shoot count for GSN-12 under these conditions;while STN-468 reached 6.00 shoots under the conditions of 10 mg·L^(-1) KIN preconditioning,MS with 0.05 mg·L^(-1) KIN(postconditioning)and 75.0%red LED.Rooting was successfully achieved with naphthalene acetic acid and activated charcoal.Additionally,three different powerful AI-based models,namely,extreme gradient boost(XGBoost),random forest(RF),and the artificial neural network-based multilayer perceptron(MLP)regression models validated the findings.Conclusion GSN-12 outperformed STN-468 with optimal results from 5 mg·L^(-1) KIN+1/4MS+80%red LED.Application of machine learning-based prediction models to optimize cotton tissue culture protocols for shoot regeneration is helpful to improve cotton regeneration efficiency.
基金funded by the National Key R&D Program of China,Grant No.2024YFF0504904.
文摘The packaging quality of coaxial laser diodes(CLDs)plays a pivotal role in determining their optical performance and long-term reliability.As the core packaging process,high-precision laser welding requires precise control of process parameters to suppress optical power loss.However,the complex nonlinear relationship between welding parameters and optical power loss renders traditional trial-and-error methods inefficient and imprecise.To address this challenge,a physics-informed(PI)and data-driven collaboration approach for welding parameter optimization is proposed.First,thermal-fluid-solid coupling finite element method(FEM)was employed to quantify the sensitivity of welding parameters to physical characteristics,including residual stress.This analysis facilitated the identification of critical factors contributing to optical power loss.Subsequently,a Gaussian process regression(GPR)model incorporating finite element simulation prior knowledge was constructed based on the selected features.By introducing physics-informed kernel(PIK)functions,stress distribution patterns were embedded into the prediction model,achieving high-precision optical power loss prediction.Finally,a Bayesian optimization(BO)algorithm with an adaptive sampling strategy was implemented for efficient parameter space exploration.Experimental results demonstrate that the proposedmethod effectively establishes explicit physical correlations between welding parameters and optical power loss.The optimized welding parameters reduced optical power loss by 34.1%,providing theoretical guidance and technical support for reliable CLD packaging.
基金supported by the National Key Research and Development Program of China(No.2022YFA1204800)the Scientific Research Innovation Capability Support Project for Young Faculty(No.ZYGXQNJSKYCXNLZCXM-I25),China+1 种基金the National Natural Science Foundation of China(No.62274144)the Zhejiang Provincial Government,China.
文摘Perovskite light-emitting diodes(PeLEDs)have shown outstanding potential in next-generation lighting and display owing to the advantages of broad spectral tunability,excellent color purity,high photoluminescence quantum yields(PLQYs),and low processing cost.Device efficiency and stability are crucial indicators to evaluate whether a PeLED can meet commercial application requirements.In this review,we first discuss strategies for achieving high external quantum efficiencies(EQEs),including controlling charge injection and balance,enhancing radiative recombination,and improving light outcoupling efficiency.Next,we review recent advances in operational stability of PeLEDs and emphasize the mechanisms of degradation in PeLEDs,including ion migration,structural transformations,chemical interactions,and thermal degradation.Through detailed analysis and discussion,this review aims to facilitate progress and innovation in highly efficient and stable PeLEDs,which have significant promise for display and solid-state lighting technologies,as well as other emerging applications.
基金supported by the National Natural Science Foundation of China(No.51973020)Beijing Natural Science Foundation(No.2232052)。
文摘A binary-mixed electron transport layer(ETL)has been reported for constructing solution-processable near-infrared organic light-emitting diodes(NIR OLEDs).Relative to the single-component ETL,the binarymixed ETL composed of PDINN:TPBi can enhance the carrier transport capacity,reduce device impedance,and weaken fiuorescence quenching of the emitting layer.By carefully selecting an appropriate luminescent material Y5(a nonfullerene electron acceptor in organic solar cells)and precisely fine-tuning the molecular aggregation in active layer using a mixed solvent,the morphology is optimized and luminescence performance is enhanced,resulting in efficient NIR OLEDs with an emission peak at 890 nm.The experiment showcases a Y5-based near-infrared OLED with a maximum radiance of 34.9 W sr^(-1)m^(-2)and a maximum external quantum efficiency of 0.50%,which is among the highest values reported for nondoped fiuorescent NIR OLEDs with an emission peak over 850 nm.
基金supported by the National Natural Science Foundation of China (Nos. 62222503, 52073040 and 52130304)the Sichuan Science and Technology Program (Nos. 2024NSFSC0012,2023NSFSC1973 and 2024NSFSC1446)+2 种基金the China Postdoctoral Science Foundation (Nos. 2023M740504 and GZC20230380)the Sichuan Provincial Human Resources and Social Security Department Programthe Collaborative Innovation Center of Suzhou Nano Science&Technology
文摘Triphenylamine(TPA)is the most promising donor fragment for the construction of long-wavelength thermally activated delayed fluorescence(TADF)emitters owing to its suitable dihedral angle that could enhance radiative decay to compete with the serious non-radiative decay.However,the moderate electron-donating capacity of TPA seriously limits the selection of acceptor for constructing longwavelength TADF emitters with narrow bandgaps.To address this issue,in this work,the peripheral benzene of TPA was replaced with 1,4-benzodioxane and anisole to obtain two new electrondonating units N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-N-phenyl-2,3-dihydrobenzo[b][1,4]dioxin-6-amine(TPADBO,−5.02 eV)and 4-methoxy-N-(4-methoxyphenyl)-N-phenylaniline(TPAMO,−5.00 eV),which possess much shallower highest occupied molecule orbital(HOMO)energy levels than the prototype TPA(−5.33 eV).Based on TPA and the modified TPA donor fragments,three TADF emitters were designed and synthesized,namely Py-TPA,Py-TPADBO and Py-TPAMO,with the same acceptor fragment 12-(2,6-diisopropylphenyl)pyrido[2′,3′:5,6]pyrazino[2,3-f][1,10]phenanthroline(Py).Among them,Py-TPAMO exhibits the highest photoluminescence quantum yield of 78.4%and the smallest singlet-triplet energy gap,which is because the introduction of anisole does not cause significant molecule deformation for the excited Py-TPAMO.And Py-TPAMO-based OLEDs successfully realize a maximum external quantum efficiency of 25.5%with the emission peak at 605 nm.This work provides a series of candidate of donor fragments for the development of efficient long-wavelength TADF emitters.
基金supported by the National Key Research and Development Program of China(2024YFE0103600)the National Natural Science Foundation of China(NSFC)(62474119,62205230,and 62175171)Suzhou Key Laboratory of Functional Nano&Soft Materials,Collaborative Innovation Center of Suzhou Nano Science&Technology,the 111 Project,Joint International Research Laboratory of Carbon-Based Functional Materials and Devices.
文摘Colloidal quantum dots(CQDs)are highly regarded for their outstanding photovoltaic characteristics,including excellent color purity,stability,high photoluminescence quantum yield(PLQY),narrow emission spectra,and ease of solution processing.Despite significant progress in quantum dot light-emitting diodes(QLEDs)technology since its inception in 1994,blue QLEDs still fall short in efficiency and lifespan compared to red and green versions.The toxicity concerns associated with Cd/Pb-based quantum dots(QDs)have spurred the development of heavy-metal-free alternatives,such as groupⅡ−Ⅵ(e.g.,ZnSe-based QDs),groupⅢ−Ⅴ(e.g.,InP,GaN QDs),and carbon dots(CDs).In this review,we discuss the key properties and development history of quantum dots(QDs),various synthesis approaches,the role of surface ligands,and important considerations in developing core/shell(C/S)structured QDs.Additionally,we provide an outlook on the challenges and future directions for blue QLEDs.
基金This work was financially supported by the Department of Science and Technology of Sichuan Province(No.2020YJ0157).
文摘A red-emitting phosphor Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) with partial Al^(3+)/P^(5+) substitution on Si^(4+) was synthesized via a simple solid-state method,and the effects of the introduction of the M^(3+/5+)(M=Al,P)ions on the crystal structure and photoluminescence performance of Ca_(2.91)Si_(2−x)M_(x)O_(7):0.09Eu^(3+) phosphors were investigated.The X-ray diffraction(XRD),energy-dispersive X-ray spectroscopy(EDS),and X-ray photoelectron spectroscopy(XPS)results revealed that the structure of Ca_(3)Si_(2)O_(7) remained the same after the introduction of Al^(3+) and P^(5+) ions.The characteristic emission of Eu^(3+)-doped Ca_(3)Si_(2−x)M_(x)O_(7) phosphors exhibited two main peaks at 617 nm(red)and 593 nm(orange)under excitation at 394 nm,which originated from the^(5)D_(0)→^(7)F_(2)and^(5)D_(0)→^(7)F_(1) electron transitions of Eu^(3+) ions.After the partial substitution of Al^(3+) and P^(5+),the red emission intensities of the Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) phosphors were significantly enhanced by 1.88-and 1.42-fold,respectively,which is attributed to the crystal-field effect around Eu^(3+).Meanwhile,the luminescence intensities of the Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+) and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) phosphors at 210℃ were 79.36%and 77.53%of those at 30°C,respectively,indicating their excellent thermal stability.Moreover,the as-prepared Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+)and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) red-emitting phosphors were combined with a near-ultraviolet chip of 395 nm to fabricate red-light-emitting diode(LED)and white(w)-LED devices with excellent chromaticity features.In summary,Al^(3+)/P^(5+)-substituted Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) can serve as red-emitting phosphors for applications in w-LEDs.
