Persistent Luminescence(PersL)materials,which use traps to store energy and emit photons over a long period,have found important applications in the fields of optical information storage,security labeling,and biologic...Persistent Luminescence(PersL)materials,which use traps to store energy and emit photons over a long period,have found important applications in the fields of optical information storage,security labeling,and biological imaging.The trap depth is a crucial factor determining the performance of these materials;however,achieving the desired trap depth with high precision remains a great challenge.Here,we provide double perovskite phosphors(Cs_(2)SnCl_(6)-Cs_(2)ZrCl_(6)-Cs_(2)HfCl_(6)series)with highly compatible crystal structures,enabling continuous and precise tuning of trap depth over an ultra-wide range of 0.11-1.25 eV.By incorporating W4+as the luminescent centers,these phosphors exhibit outstanding near-infrared(NIR)PersL performance at approximately 900 nm and a lasting emission duration exceeding 10 h.The underlying mechanism of PersL is elucidated,and the wide-range tunability of trap depth is attributed to the universal applicability of band-gap engineering in the entire material system.Furthermore,we demonstrate the practical application of these materials by designing a flexible detector plate for X-ray imaging.The detector plate exhibits a storage time of more than 1 week,a detection limit of 0.83μGyair·s^(-1)in the near-infrared region,and real-time and delay-time imaging resolutions of 14.2 lp·mm^(-1)and 2.5 lp·mm^(-1),respectively.These attributes demonstrate strong potential for X-ray luminescence extension imaging.展开更多
Mechanoluminescence(ML)is bringing a paradigm-shifting for next-generation lightbased human–robot interaction.However,the overlooked character of ML temporal dynamic response remains a critical barrier to overcoming ...Mechanoluminescence(ML)is bringing a paradigm-shifting for next-generation lightbased human–robot interaction.However,the overlooked character of ML temporal dynamic response remains a critical barrier to overcoming the limitation of mechanooptical conversion efficiency.Here,by resolving the dynamic interplay among stimuli rate,interfacial charge accumulation and ML performance of three typical materials,like ZnS:Cu^(2+),SrAl_(2)O_(4):Eu^(2+),Dy^(3+),Y_(3)Al_(5)O_(12):Ce^(3+),the cognition of ML has been deeply understand.Obviously,the ML performance is predominantly governed by the crosscoupling of stimuli rate and stimuli time rather than absolute stress magnitude.For the first time,the optimal stretching stimulation rate for commercial ZnS:Cu^(2+),SrAl_(2)O_(4):Eu^(2+),Dy^(3+)and Y_(3)Al_(5)O_(12):Ce^(3+)are respectively determined as~10.3 Mpa/s,~11.0 Mpa/s,~31.9 Mpa/s,which is of great significance for obtaining high-performance ML behavior,and an ubiquitous ML hysteresis phenomenon is demonstrated originating from a time-consuming mechano-electro-optical conversion process even existing in trap-controlled SrAl_(2)O_(4):Eu^(2+),Dy^(3+).Moreover,a qualitative relationship for ML brightness(MLB),stimuli rate(sr),stimuli time(st),inherent interfacial triboelectricity coefficient(iitre)and relative interfacial triboelectricity coefficient(ritre)is established as ML B=f(sr)*g(st)*p(iitre)*q(ritre)for guiding the design of ML elastomers.For instance,based on this equation,a topology-optimized Y_(3)Al_(5)O_(12):Ce^(3+)@polydimethylsiloxane(PDMS)elastomer is engineered,achieving unprecedented 693 times brighter emission,78%lower stress threshold and 20%lighter weight,which is successfully applied in remote control(~450 m)of quadruped robot.Three main contributions of this work include:(i)demonstrating the influence law of temporal dynamic stimulation on ML performance.(ii)resolving long-standing mechano-optical asynchrony debates.(iii)establishing a universal guideline for designing high-performance ML platforms.展开更多
A three-layered phosphor structure was designed and prepared by the spin coating of BaSi_(2)N_(2)O_(2):Eu(cyan-emitting)and(Sr,Ca)AlSiN_(3):Eu(red-emitting)phosphor films on the yellowemitting Y_(3)Al_(5)O_(12):Ce(YAG...A three-layered phosphor structure was designed and prepared by the spin coating of BaSi_(2)N_(2)O_(2):Eu(cyan-emitting)and(Sr,Ca)AlSiN_(3):Eu(red-emitting)phosphor films on the yellowemitting Y_(3)Al_(5)O_(12):Ce(YAG:Ce)phosphor ceramic synthesized by the solid-state reaction under vacuum sintering.In order to achieve high color rendering lighting,the influence of the composition and structure of the three-layered phosphors on the optical,thermal,and electrical properties of the chip-on-board(COB)packaged white-light-emitting diodes(WLEDs)was studied systematically.The WLED with the structure of“red+cyan+yellow”(R+C+Y)three-layered phosphor generated neutral white light and had a luminous efficacy of 75 lm/W,the fidelity index(R_(f))of 93,the gamut index(R_(g))of 97,and the correlated color temperature(CCT)of 3852 K.Under the excitation of laser diode(LD),the layer-structured phosphor yielded the white light with a luminous efficacy of 120 lm/W,color rendering index(CRI)of 90,and CCT of 5988 K.The result indicates that the three-layered phosphor structure is a promising candidate to achieve high color rendering and high luminous efficacy lighting.展开更多
The first carbon dot(CD)-based organic long persistent luminescence(OLPL)system exhibiting more than 1 h of duration was developed.In contrast to the established OLPL systems,herein,the reported CDs-based system(named...The first carbon dot(CD)-based organic long persistent luminescence(OLPL)system exhibiting more than 1 h of duration was developed.In contrast to the established OLPL systems,herein,the reported CDs-based system(named m-CDs@CA)can be facilely and effectively fabricated using a household microwave oven,and more impressively,its LPL can be observed under ambient conditions and even in aqueous media.XRD and TEM characterizations,afterglow decay,time-resolved spectroscopy,and ESR analysis were performed,showing the successful composition of CDs and.CA,the formation of exciplexes and long-lived charged-separated states.Further studies suggest that the production of covalent bonds between CA and CDs plays pivotal roles in activating LPL and preventing its quenching from oxygen and water.To the best of our knowledge,this is a very rare example of an OLPL system that exhibits hourlevel afterglow under ambient conditions.Finally,applications of m-CDs@C.A in glow-in-the-dark paints for emergency signs and multicolored luminous pearls were preliminarily demonstrated.This work may provide new insights for the development of rare earth-free and robust OLPL materials.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52172156,12474412)the Natural Science Foundation of Fujian Province(No.2023J06005)+2 种基金the Natural Science Foundation of Guangdong Province(No.2024A1515011197)the Fundamental Research Funds for the Central Universities(No.20720240057)The DFT calculations in this work was done with the assistance of the Intelligent Computing Center of Tan Kah Kee Innovation Laboratory(IKKEM).
文摘Persistent Luminescence(PersL)materials,which use traps to store energy and emit photons over a long period,have found important applications in the fields of optical information storage,security labeling,and biological imaging.The trap depth is a crucial factor determining the performance of these materials;however,achieving the desired trap depth with high precision remains a great challenge.Here,we provide double perovskite phosphors(Cs_(2)SnCl_(6)-Cs_(2)ZrCl_(6)-Cs_(2)HfCl_(6)series)with highly compatible crystal structures,enabling continuous and precise tuning of trap depth over an ultra-wide range of 0.11-1.25 eV.By incorporating W4+as the luminescent centers,these phosphors exhibit outstanding near-infrared(NIR)PersL performance at approximately 900 nm and a lasting emission duration exceeding 10 h.The underlying mechanism of PersL is elucidated,and the wide-range tunability of trap depth is attributed to the universal applicability of band-gap engineering in the entire material system.Furthermore,we demonstrate the practical application of these materials by designing a flexible detector plate for X-ray imaging.The detector plate exhibits a storage time of more than 1 week,a detection limit of 0.83μGyair·s^(-1)in the near-infrared region,and real-time and delay-time imaging resolutions of 14.2 lp·mm^(-1)and 2.5 lp·mm^(-1),respectively.These attributes demonstrate strong potential for X-ray luminescence extension imaging.
基金financially supported by National Natural Science Foundation of China(U24A20307,12304460).
文摘Mechanoluminescence(ML)is bringing a paradigm-shifting for next-generation lightbased human–robot interaction.However,the overlooked character of ML temporal dynamic response remains a critical barrier to overcoming the limitation of mechanooptical conversion efficiency.Here,by resolving the dynamic interplay among stimuli rate,interfacial charge accumulation and ML performance of three typical materials,like ZnS:Cu^(2+),SrAl_(2)O_(4):Eu^(2+),Dy^(3+),Y_(3)Al_(5)O_(12):Ce^(3+),the cognition of ML has been deeply understand.Obviously,the ML performance is predominantly governed by the crosscoupling of stimuli rate and stimuli time rather than absolute stress magnitude.For the first time,the optimal stretching stimulation rate for commercial ZnS:Cu^(2+),SrAl_(2)O_(4):Eu^(2+),Dy^(3+)and Y_(3)Al_(5)O_(12):Ce^(3+)are respectively determined as~10.3 Mpa/s,~11.0 Mpa/s,~31.9 Mpa/s,which is of great significance for obtaining high-performance ML behavior,and an ubiquitous ML hysteresis phenomenon is demonstrated originating from a time-consuming mechano-electro-optical conversion process even existing in trap-controlled SrAl_(2)O_(4):Eu^(2+),Dy^(3+).Moreover,a qualitative relationship for ML brightness(MLB),stimuli rate(sr),stimuli time(st),inherent interfacial triboelectricity coefficient(iitre)and relative interfacial triboelectricity coefficient(ritre)is established as ML B=f(sr)*g(st)*p(iitre)*q(ritre)for guiding the design of ML elastomers.For instance,based on this equation,a topology-optimized Y_(3)Al_(5)O_(12):Ce^(3+)@polydimethylsiloxane(PDMS)elastomer is engineered,achieving unprecedented 693 times brighter emission,78%lower stress threshold and 20%lighter weight,which is successfully applied in remote control(~450 m)of quadruped robot.Three main contributions of this work include:(i)demonstrating the influence law of temporal dynamic stimulation on ML performance.(ii)resolving long-standing mechano-optical asynchrony debates.(iii)establishing a universal guideline for designing high-performance ML platforms.
基金supported by the National Key R&D Program of China(Grant No.2017YFB0310500)the National Natural Science Foundation of China(Grant No.61775226)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDA22010301)the key research project of the frontier science of the Chinese Academy of Sciences(No.QYZDB-SSW-JSC022).
文摘A three-layered phosphor structure was designed and prepared by the spin coating of BaSi_(2)N_(2)O_(2):Eu(cyan-emitting)and(Sr,Ca)AlSiN_(3):Eu(red-emitting)phosphor films on the yellowemitting Y_(3)Al_(5)O_(12):Ce(YAG:Ce)phosphor ceramic synthesized by the solid-state reaction under vacuum sintering.In order to achieve high color rendering lighting,the influence of the composition and structure of the three-layered phosphors on the optical,thermal,and electrical properties of the chip-on-board(COB)packaged white-light-emitting diodes(WLEDs)was studied systematically.The WLED with the structure of“red+cyan+yellow”(R+C+Y)three-layered phosphor generated neutral white light and had a luminous efficacy of 75 lm/W,the fidelity index(R_(f))of 93,the gamut index(R_(g))of 97,and the correlated color temperature(CCT)of 3852 K.Under the excitation of laser diode(LD),the layer-structured phosphor yielded the white light with a luminous efficacy of 120 lm/W,color rendering index(CRI)of 90,and CCT of 5988 K.The result indicates that the three-layered phosphor structure is a promising candidate to achieve high color rendering and high luminous efficacy lighting.
基金the National Natural Science Foundation of China(52003284,51872300,and U1832110)the China Postdoctoral Science Foundation(BX20190338)the S&T Innovation 2025 Major Special Programme of Ningbo(2018B10054)for financially supporting this work.
文摘The first carbon dot(CD)-based organic long persistent luminescence(OLPL)system exhibiting more than 1 h of duration was developed.In contrast to the established OLPL systems,herein,the reported CDs-based system(named m-CDs@CA)can be facilely and effectively fabricated using a household microwave oven,and more impressively,its LPL can be observed under ambient conditions and even in aqueous media.XRD and TEM characterizations,afterglow decay,time-resolved spectroscopy,and ESR analysis were performed,showing the successful composition of CDs and.CA,the formation of exciplexes and long-lived charged-separated states.Further studies suggest that the production of covalent bonds between CA and CDs plays pivotal roles in activating LPL and preventing its quenching from oxygen and water.To the best of our knowledge,this is a very rare example of an OLPL system that exhibits hourlevel afterglow under ambient conditions.Finally,applications of m-CDs@C.A in glow-in-the-dark paints for emergency signs and multicolored luminous pearls were preliminarily demonstrated.This work may provide new insights for the development of rare earth-free and robust OLPL materials.
