Nowadays,high-quality phosphor-converted white light-emitting diodes(pc-WLEDs)ought to include cyan-emitting phosphors allowing for full-spectrum light similar to sunlight.Herein,we report a garnetstructured Ce^(3+)-d...Nowadays,high-quality phosphor-converted white light-emitting diodes(pc-WLEDs)ought to include cyan-emitting phosphors allowing for full-spectrum light similar to sunlight.Herein,we report a garnetstructured Ce^(3+)-doped SrLu_(2)Ga_(1.5)Al_(2.5)SiO_(12)(SLGASO)phosphor that significantly compensates for the absence of cyan light,known as the"cyan cavity".The SLGASO host crystallizes into a cubic structure with the Ia3d space group.The cell parameters were determined using Rietveld refinement.Under430 nm blue excitation,SLGASO:Ce^(3+)emits intense cyan-green light in the 450-700 nm wavelength range.The representative SLGASO:0.07Ce^(3+)phosphor has an internal quantum efficiency(IQE)of 95.4%and excellent thermal stability,remaining 92.7%of its initial emission intensity at 152℃.After 155 d of immersion in water,the luminous intensity of SLGASO:0.07Ce^(3+)remains constant,confirming its waterproofness.Furthermore,a pc-WLED device with luminous efficiency(LE)of 101.58 lm/W,color rendering index(Ra)of 91,correlated color temperature(CCT)of 4536 K,and Commission Internationale de L'Eclairage(CIE)chromaticity coordinates of(0.3555,0.3390)was fabricated by combining asprepared cyan-green-emitting SLGASO:0.07Ce^(3+),yellow-emitting Y_(3)Al_(5)O_(12):Ce^(3+)(YAG:Ce^(3+)),and redemitting(Ca,Sr)AlSiN_(3):Eu^(2+)phosphors,as well as a 450 nm blue chip.These findings indicate that SLGASO:0.07Ce^(3+)phosphor can bridge the cyan gap and improve the performance of as-fabricated fullvisible-spectrum WLEDs.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
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
基金supported by the National Natural Science Foundations of China(21801254,52002411,52272174,22205017,U1301242)China Postdoctoral Science Foundation(2022M720400,2023M743978)+1 种基金Specialized Research Fund for the Doctoral Program of Higher Education of China(20130171130001)the Ministry of Science,Technological Development,and Innovation of the Republic of Serbia(451-03-66/2024-03/200017)。
文摘Nowadays,high-quality phosphor-converted white light-emitting diodes(pc-WLEDs)ought to include cyan-emitting phosphors allowing for full-spectrum light similar to sunlight.Herein,we report a garnetstructured Ce^(3+)-doped SrLu_(2)Ga_(1.5)Al_(2.5)SiO_(12)(SLGASO)phosphor that significantly compensates for the absence of cyan light,known as the"cyan cavity".The SLGASO host crystallizes into a cubic structure with the Ia3d space group.The cell parameters were determined using Rietveld refinement.Under430 nm blue excitation,SLGASO:Ce^(3+)emits intense cyan-green light in the 450-700 nm wavelength range.The representative SLGASO:0.07Ce^(3+)phosphor has an internal quantum efficiency(IQE)of 95.4%and excellent thermal stability,remaining 92.7%of its initial emission intensity at 152℃.After 155 d of immersion in water,the luminous intensity of SLGASO:0.07Ce^(3+)remains constant,confirming its waterproofness.Furthermore,a pc-WLED device with luminous efficiency(LE)of 101.58 lm/W,color rendering index(Ra)of 91,correlated color temperature(CCT)of 4536 K,and Commission Internationale de L'Eclairage(CIE)chromaticity coordinates of(0.3555,0.3390)was fabricated by combining asprepared cyan-green-emitting SLGASO:0.07Ce^(3+),yellow-emitting Y_(3)Al_(5)O_(12):Ce^(3+)(YAG:Ce^(3+)),and redemitting(Ca,Sr)AlSiN_(3):Eu^(2+)phosphors,as well as a 450 nm blue chip.These findings indicate that SLGASO:0.07Ce^(3+)phosphor can bridge the cyan gap and improve the performance of as-fabricated fullvisible-spectrum WLEDs.
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 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.
