While the“amorphous to crystalline”transformation process,which has significant potential for application,has been widely studied,the microscopic mechanism on the nanometer scale is not fully understood.In contrast ...While the“amorphous to crystalline”transformation process,which has significant potential for application,has been widely studied,the microscopic mechanism on the nanometer scale is not fully understood.In contrast to common heat-driven phase transformations,the present study demonstrated the force-driven moisture-mediated nanocrystallization of perovskite CsPbBr_(3)precipitated from a glass matrix.In the present case,the breakage of the glass network under shearing force produces high-energy sites to absorb H2O molecules/clusters from ambient moisture,and the hydration process promotes the crystallization process.Microscratch analysis combined with confocal laser scanning microscopy revealed that the distribution of CsPbBr_(3)nanocrystals almost reproduced that of the localized stress field and clearly reflected the crack propagation pathways.The potential applications of perovskite glass in the optical sensing of force and moisture are also explored.Our findings provide insight into crystal nucleation/growth in glass,as well as understanding the dynamics of crack propagation during the brittle fracture process.展开更多
The pursuit of high-brightness solid-state lighting(SSL)stimulates the development of all-inorganic color converters with high robustness.It is required that the fluorescent material is able to cope with the extreme c...The pursuit of high-brightness solid-state lighting(SSL)stimulates the development of all-inorganic color converters with high robustness.It is required that the fluorescent material is able to cope with the extreme condition generated from the irradiation of high-power-density excitation light.As such,in this work,we developed a new composite color converter,i,e.,Y_(3)Al_(5)O_(12):Ce^(3+)phosphor-in-silica glass ceramic(YAG:Ce^(3+)PiSGC).Remarkably,the amorphous SiO_(2)matrix spontaneously transforms into tetragonal SiO_(2)crystallites during co-sintering with crystallization fraction reaching up to>90%(almost full ceramization).The activation energy for crystallization E_(c)and Avrami index n of amorphous silica oxide are 298.5 kJ/mol and 1.71,indicating the diffusion-controlled glass crystallization mechanism.The fabricated prototype high-power phosphor-converted white light-emitting diode(pc-wLED)and phosphor-converted white laser diode(pc-wLD)based on YAG:Ce^(3+)PiSGC show satisfactory photometric/colorimetric parameters.The developed color co nverters have combined merits of environmental protection property,cost-effective manufacturing,good luminescent performance,and easy scalability.This study highlights a new kind of opto-functional composite material and its application as an efficient color converter in high-power solid-state lightings.展开更多
The structure of electroslag remelting-type CaF_(2)–CaO–Al_(2)O_(3)–CeO_(2)slag with various CaO/Al_(2)O_(3)mass ratios and its correlation with viscosity and surface tension were investigated.The Raman analysis of...The structure of electroslag remelting-type CaF_(2)–CaO–Al_(2)O_(3)–CeO_(2)slag with various CaO/Al_(2)O_(3)mass ratios and its correlation with viscosity and surface tension were investigated.The Raman analysis of the slag shows that with increasing CaO/Al_(2)O_(3)mass ratio from 0.70 to 1.29 in the slag,the polymerization degree of the slag decreased,which was because more complex[AlO_(4)]-tetrahedral units of Q_(Al)^(3) and Q_(Al)^(4)were depolymerized to form relatively simpler structural units Q_(Al)^(0),Q_(Al)^(1),and Q_(Al)^(2),and the excess oxygen ions introduced by CaO promoted the transformation of[AlO_(4)]-tetrahedral units to[AlO_(6)]-octahedral units.Increasing CaO/Al_(2)O_(3)mass ratio has an obvious effect on reducing the viscosity and activation energy for viscous flow of the slag,resulting from the depolymerization of the slag.Owing to the decrease in the polymerization degree and the increase in the total Ca^(2+)content of the slag,the surface tension of the slag increases with the increase in CaO/Al_(2)O_(3)mass ratio.The surface tension of the slag changes slightly with the temperature,irrespective of CaO/Al_(2)O_(3)mass ratio from 0.70 to 1.29 in the slag.展开更多
In this work,we discovered an unexpected mechanoluminescence (ML) phenomena occurring when transforming amorphous into crystalline,due to the stress-induced precipitation of CsPbBr3 perovskite nanocrystals on glass su...In this work,we discovered an unexpected mechanoluminescence (ML) phenomena occurring when transforming amorphous into crystalline,due to the stress-induced precipitation of CsPbBr3 perovskite nanocrystals on glass surface.It is revealed that,unlike the conventional thermal-induced phase transformation mechanism,the breakage of bonding of glass network provides the energy for nucleation and growth,and the shear stress avoids the long-range migration of structural units for crystallization.Such unique ML phenomenon enables the visualization of dynamical force that is inaccessible by common strategy,and so,opens up some novel applications,such as the pressure-sensitive "glassy pencil" to learn people's writing habits,and the pb^2+-detection with good sensitivity and selectivity.These findings not only demonstrate an effective route for the preparation of perovskite materials in a green,time-saving,low cost,and scalable way,enrich the knowledge of glass crystallization mechanism,but also exploit a useful avenue to quantitatively visualize the dynamical force.展开更多
The launch of the big data era puts forward challenges for information preservation technology,both in storage capacity and security.Herein,a brand new optical storage medium,transparent glass ceramic(TGC)embedded wit...The launch of the big data era puts forward challenges for information preservation technology,both in storage capacity and security.Herein,a brand new optical storage medium,transparent glass ceramic(TGC)embedded with photostimulated LiGa5O8:Mn2+nanocrystals,capable of achieving bit-by-bit optical data write-in and read-out in a photon trapping/detrapping mode,is developed.The highly ordered nanostructure enables light–matter interaction with high encoding/decoding resolution and low bit error rate.Importantly,going beyond traditional 2D optical storage,the high transparency of the studied bulk medium makes 3D volumetric optical data storage(ODS)possible,which brings about the merits of expanded storage capacity and improved information security.Demonstration application confirmed the erasable-rewritable 3D storage of binary data and display items in TGC with intensity/wavelength multiplexing.The present work highlights a great leap in photostimulated material for ODS application and hopefully stimulates the development of new multi-dimensional ODS media.展开更多
Up-to-date laser-driven lightings confront a challenge of simultaneously achieving good photometric and chromatic performances.Herein,the coupling of“patterned package design”and“phosphor wheel”was proposed and de...Up-to-date laser-driven lightings confront a challenge of simultaneously achieving good photometric and chromatic performances.Herein,the coupling of“patterned package design”and“phosphor wheel”was proposed and demonstrated effectively to deal with this tough issue,based on a new architecture of CaAlSiN3:Eu2+(CASN:Eu)glass ceramic film(GCF)on Y_(3)Al_(5)O_(12):Ce^(3+)(YAG:Ce)GC plate.The fabricated composite has no interface between the two functional layers and retains the admirable luminescent features from CASN:Eu and YAG:Ce for the microstructural integrity during co-sintering.The studies on laser-microcrystalline interactions reveal that the luminescence saturation is almost determined by thermal quenching for YAG:Ce,but is ascribed to thermal/intensity quenching which are equally crucial for CASN:Eu.Benefiting from the elaborate architecture design,good color chromaticity tunability was obtained,and severe photon reabsorption was reduced.Moreover,accompanied with the rotation induced increase of thermal convection to air and pulse-like excitation,the constructed lighting engine under blue laser driven shows bright white light with luminous flux(LF)higher than 1000 lm,adjustable chromaticity from cool to warm,and improved color rendering index(CRI)approaching to 70.展开更多
Single-band red upconversion luminescence(UCL) is vital to in vivo bioimaging as well as "see and treat" biomedicines. Herein, starting with the previously reported β-NaErF4:Tm UCNPs, we examined the effect...Single-band red upconversion luminescence(UCL) is vital to in vivo bioimaging as well as "see and treat" biomedicines. Herein, starting with the previously reported β-NaErF4:Tm UCNPs, we examined the effects of both Yb^(3+) doping and inert shell coating on the red-to-green(R/G) ratio for Er3+ based UCL. The doping of Yb^(3+) into the β-NaErF4:Tm3+ core not only enhances the whole UCL intensity, but also raises the R/G ratio by 1.25 times. In addition, the coating of an inert NaYF4 shell, which is usually adopted for the enhancement of UCL intensity, further boosts the R/G value up to as high as 77.92. This work may benefit the potential bioimaging application of single-band red UCL.展开更多
基金supported by the National Natural Science Foundation of China(52372161,51972303,U2005213,and 11974350)the Science Fund for Distinguished Young Scholars of Fujian Province(2022J06030)+1 种基金the STS Project of Fujian-CAS(2022T3069)the 14th Five Year Scientific and Technological Innovation Planning Project of FJIRSM(CXZX-2022-GH11)。
文摘While the“amorphous to crystalline”transformation process,which has significant potential for application,has been widely studied,the microscopic mechanism on the nanometer scale is not fully understood.In contrast to common heat-driven phase transformations,the present study demonstrated the force-driven moisture-mediated nanocrystallization of perovskite CsPbBr_(3)precipitated from a glass matrix.In the present case,the breakage of the glass network under shearing force produces high-energy sites to absorb H2O molecules/clusters from ambient moisture,and the hydration process promotes the crystallization process.Microscratch analysis combined with confocal laser scanning microscopy revealed that the distribution of CsPbBr_(3)nanocrystals almost reproduced that of the localized stress field and clearly reflected the crack propagation pathways.The potential applications of perovskite glass in the optical sensing of force and moisture are also explored.Our findings provide insight into crystal nucleation/growth in glass,as well as understanding the dynamics of crack propagation during the brittle fracture process.
基金Project supported by the National Natural Science Foundation of China(U2005213,51972303,11974350)Science Fund for Distinguished Young Scholars of Fujian Province(2022J06030)+2 种基金Science Fund of Fujian Province(2022J05091)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZR134)the STS Project of Fujian-CAS(2022T3069)。
文摘The pursuit of high-brightness solid-state lighting(SSL)stimulates the development of all-inorganic color converters with high robustness.It is required that the fluorescent material is able to cope with the extreme condition generated from the irradiation of high-power-density excitation light.As such,in this work,we developed a new composite color converter,i,e.,Y_(3)Al_(5)O_(12):Ce^(3+)phosphor-in-silica glass ceramic(YAG:Ce^(3+)PiSGC).Remarkably,the amorphous SiO_(2)matrix spontaneously transforms into tetragonal SiO_(2)crystallites during co-sintering with crystallization fraction reaching up to>90%(almost full ceramization).The activation energy for crystallization E_(c)and Avrami index n of amorphous silica oxide are 298.5 kJ/mol and 1.71,indicating the diffusion-controlled glass crystallization mechanism.The fabricated prototype high-power phosphor-converted white light-emitting diode(pc-wLED)and phosphor-converted white laser diode(pc-wLD)based on YAG:Ce^(3+)PiSGC show satisfactory photometric/colorimetric parameters.The developed color co nverters have combined merits of environmental protection property,cost-effective manufacturing,good luminescent performance,and easy scalability.This study highlights a new kind of opto-functional composite material and its application as an efficient color converter in high-power solid-state lightings.
基金the National Natural Science Foundation of China(Grant No.52104339)the Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking(Grant No.KF-20-3)is greatly acknowledged.
文摘The structure of electroslag remelting-type CaF_(2)–CaO–Al_(2)O_(3)–CeO_(2)slag with various CaO/Al_(2)O_(3)mass ratios and its correlation with viscosity and surface tension were investigated.The Raman analysis of the slag shows that with increasing CaO/Al_(2)O_(3)mass ratio from 0.70 to 1.29 in the slag,the polymerization degree of the slag decreased,which was because more complex[AlO_(4)]-tetrahedral units of Q_(Al)^(3) and Q_(Al)^(4)were depolymerized to form relatively simpler structural units Q_(Al)^(0),Q_(Al)^(1),and Q_(Al)^(2),and the excess oxygen ions introduced by CaO promoted the transformation of[AlO_(4)]-tetrahedral units to[AlO_(6)]-octahedral units.Increasing CaO/Al_(2)O_(3)mass ratio has an obvious effect on reducing the viscosity and activation energy for viscous flow of the slag,resulting from the depolymerization of the slag.Owing to the decrease in the polymerization degree and the increase in the total Ca^(2+)content of the slag,the surface tension of the slag increases with the increase in CaO/Al_(2)O_(3)mass ratio.The surface tension of the slag changes slightly with the temperature,irrespective of CaO/Al_(2)O_(3)mass ratio from 0.70 to 1.29 in the slag.
基金the National Natural Science Foundation of China (Nos.11674318, 11774346, 5187228& and 51472242)the National Key R&D Program of China (No. 2016YFB0701003)the Chunmiao Project of the Haixi Institute of the Chinese Academy of Sciences (No.CMZX-2017-002).
文摘In this work,we discovered an unexpected mechanoluminescence (ML) phenomena occurring when transforming amorphous into crystalline,due to the stress-induced precipitation of CsPbBr3 perovskite nanocrystals on glass surface.It is revealed that,unlike the conventional thermal-induced phase transformation mechanism,the breakage of bonding of glass network provides the energy for nucleation and growth,and the shear stress avoids the long-range migration of structural units for crystallization.Such unique ML phenomenon enables the visualization of dynamical force that is inaccessible by common strategy,and so,opens up some novel applications,such as the pressure-sensitive "glassy pencil" to learn people's writing habits,and the pb^2+-detection with good sensitivity and selectivity.These findings not only demonstrate an effective route for the preparation of perovskite materials in a green,time-saving,low cost,and scalable way,enrich the knowledge of glass crystallization mechanism,but also exploit a useful avenue to quantitatively visualize the dynamical force.
基金supported by the National Natural Science Foundation of China(51872288,11774346,51972303 and 11974350)the Natural Science Foundation of Fujian Province(2019J01122).
文摘The launch of the big data era puts forward challenges for information preservation technology,both in storage capacity and security.Herein,a brand new optical storage medium,transparent glass ceramic(TGC)embedded with photostimulated LiGa5O8:Mn2+nanocrystals,capable of achieving bit-by-bit optical data write-in and read-out in a photon trapping/detrapping mode,is developed.The highly ordered nanostructure enables light–matter interaction with high encoding/decoding resolution and low bit error rate.Importantly,going beyond traditional 2D optical storage,the high transparency of the studied bulk medium makes 3D volumetric optical data storage(ODS)possible,which brings about the merits of expanded storage capacity and improved information security.Demonstration application confirmed the erasable-rewritable 3D storage of binary data and display items in TGC with intensity/wavelength multiplexing.The present work highlights a great leap in photostimulated material for ODS application and hopefully stimulates the development of new multi-dimensional ODS media.
基金This work is supported by the National Natural Science Foundation of China(Grant Nos.U2005213,11774346,51972303,51872288,and 11974350)the Fujian Provincial Key Project of Science&Technology(Grant No.2020H0035)the Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZR134).
文摘Up-to-date laser-driven lightings confront a challenge of simultaneously achieving good photometric and chromatic performances.Herein,the coupling of“patterned package design”and“phosphor wheel”was proposed and demonstrated effectively to deal with this tough issue,based on a new architecture of CaAlSiN3:Eu2+(CASN:Eu)glass ceramic film(GCF)on Y_(3)Al_(5)O_(12):Ce^(3+)(YAG:Ce)GC plate.The fabricated composite has no interface between the two functional layers and retains the admirable luminescent features from CASN:Eu and YAG:Ce for the microstructural integrity during co-sintering.The studies on laser-microcrystalline interactions reveal that the luminescence saturation is almost determined by thermal quenching for YAG:Ce,but is ascribed to thermal/intensity quenching which are equally crucial for CASN:Eu.Benefiting from the elaborate architecture design,good color chromaticity tunability was obtained,and severe photon reabsorption was reduced.Moreover,accompanied with the rotation induced increase of thermal convection to air and pulse-like excitation,the constructed lighting engine under blue laser driven shows bright white light with luminous flux(LF)higher than 1000 lm,adjustable chromaticity from cool to warm,and improved color rendering index(CRI)approaching to 70.
基金Project supported by the National Key Research and Development Program of China(2016YFB0701003)the National Natural Science Foundation of China(51872288,11674318,51472242,21673242)
文摘Single-band red upconversion luminescence(UCL) is vital to in vivo bioimaging as well as "see and treat" biomedicines. Herein, starting with the previously reported β-NaErF4:Tm UCNPs, we examined the effects of both Yb^(3+) doping and inert shell coating on the red-to-green(R/G) ratio for Er3+ based UCL. The doping of Yb^(3+) into the β-NaErF4:Tm3+ core not only enhances the whole UCL intensity, but also raises the R/G ratio by 1.25 times. In addition, the coating of an inert NaYF4 shell, which is usually adopted for the enhancement of UCL intensity, further boosts the R/G value up to as high as 77.92. This work may benefit the potential bioimaging application of single-band red UCL.
