Eu^(2+)doped fluorosilicate glass-ceramics containing BaF_(2) nanocrystals have high potential as spectral conversion materials for organic solar cells.However,it is difficult to realize the efficient design of BaF_(2...Eu^(2+)doped fluorosilicate glass-ceramics containing BaF_(2) nanocrystals have high potential as spectral conversion materials for organic solar cells.However,it is difficult to realize the efficient design of BaF_(2):Eu^(2+)doped fluorosilicate glass and to vividly observe the glass microstructure in experiment through traditional trial-and-error glass preparation method.BaF_(2):Eu^(2+)doped fluorosilicate glassceramics with high transparency,and high photoluminescence(PL)performance were predicted,designed and prepared via molecular dynamics(MD)simulation method.By MD simulation prediction,self-organized nanocrystallization was realized to inhibit the abnormal growth of nanocrystals due to[AlO_(4)]tetrahedra formed in the fluoride-oxide interface.The introduction of NaF reduces the effective phonon energy of the glass because Na+will prompt Al^(3+)to migrate from the fluoride phase to the silicate phase and interface.The local environment of Eu^(2+)is optimized by predicting the doping concentration of EuF_(3) and 2 mol%EuF3 is the best concentration in this work.Glass-ceramics sample GC2Eu as spectral conversion layer was successfully applied on organic solar cells to obtain more available visible phonons with a high photoelectric conversion efficiency(PCE).This work confirms the guidance of molecular dynamics simulation methods for fluorosilicate glasses design.展开更多
This study aims to systematically monitor the deposition rate of chloride ions at nine distinct locations on Zhairuoshan Island,situated in the East China Sea,over a 16-month period.The research investigates the effec...This study aims to systematically monitor the deposition rate of chloride ions at nine distinct locations on Zhairuoshan Island,situated in the East China Sea,over a 16-month period.The research investigates the effects of offshore distance,azimuth,seasonality,rainfall,and wind conditions on the chloride ion deposition rate.Additionally,an atmospheric corrosion test on Q235 steel is conducted at four representative sites on the island,with subsequent comparisons made to the chloride ion deposition rates observed.The findings indicate that wind energy has a more significant impact on the rate of chloride ion deposition.Furthermore,corrosion tests on Q235 steel demonstrate that the presence of chloride ions can accelerate the corrosion process.展开更多
The rapid development of phosphor-converted white light emitting diodes(pc-WLEDs)requires new red phosphors with efficient and thermally stable luminescence for high-quality warm-white lighting.However,it is still a c...The rapid development of phosphor-converted white light emitting diodes(pc-WLEDs)requires new red phosphors with efficient and thermally stable luminescence for high-quality warm-white lighting.However,it is still a challenge to discover red phosphors with facile synthesis,high internal quantum efficiency(IQE),excellent thermal stability and high color purity.Herein,a novel red-emitting Eu^(3+)activated barium dialuminum digermanate(BaAl_(2)Ge_(3)O_(8),EAGO)phosphor showing strong red emission at 610 nm was prepared.The IQE is improved from 32.91%to 78.84%by employing a charge compensation strategy.The lithium-ion co-dop ed BAGO:Eu^(3+)phosphor exhibits a nearly twofold increase in integral photoluminescence(PL)intensity and the high color purity reaches 94.17%.Impressively,the PL intensity of the BAGO:Eu^(3+),Li^(+)phosphor drops by only 2.6%at 150℃of that at room temperature.Finally,the pc-WLED using the red BAGO:Eu^(3+),Li^(+)phosphor exhibits white light with the chromaticity coordinate of(0.3515,0.3495),a high color-rendering index of 92 and a low correlated color temperature of 4746 K.All these results manifest that BAGO:Eu^(3+),Li^(+)phosphor is a suitable red phosphor for nearultraviolet(NUV)chip-based pc-WLEDs.展开更多
Significant developments have been made in the past few decades for lanthanide(Ln)ions doped fluorosilicate glass-ceramics(Flusi-GCs).As novel generation of luminescence materials with a wide range of applications,Flu...Significant developments have been made in the past few decades for lanthanide(Ln)ions doped fluorosilicate glass-ceramics(Flusi-GCs).As novel generation of luminescence materials with a wide range of applications,Flusi-GCs as a single host combine the advantages of glass and ceramics/crystals as well as fluorides and silicates.In this review,the chemical design principles and experimental procedures of Flusi-GCs are summarized in detail.Flusi-GCs are categorized as those containing PbxCd_(1-x)F_(2),RF_(3)(R=Y,La,Gd),MF_(2)(M=Ca,Sr,Ba),xMF_(2)-yRF_(3)(R=Y,La-Lu),mAF-nRF_(3)(A=Li,Na,K),KTF_(3)(T=Zn,Mn)and K2 SiF6 nanocrystals(NCs).Theoretical breakthroughs mainly by molecular dynamic(MD)simulation have been recapitulated as efficient routes for composition-design,nano-crystallization-prediction,and performance-optimization of Flusi-GCs containing target fluoride NCs.Essential research progresses pertaining photonic applications have been made in random lasers,communication amplifiers,optical fibers,spectral converters,white light-emitting-diodes(WLEDs),and thermal sensors.In the end,we propose three future research directions for Flusi-GCs.展开更多
With narrow red photoluminescence (PL) bands, tetravalent Mn^(4+) doped phosphors show promising prospect in commercial application to effectively expand color gamut of phosphor converted LED displays. Here, we report...With narrow red photoluminescence (PL) bands, tetravalent Mn^(4+) doped phosphors show promising prospect in commercial application to effectively expand color gamut of phosphor converted LED displays. Here, we report a type of Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) phosphors with regular cage-like micro-spherical morphologies. The micron size spherical precursors were synthesized with a propylene oxide (PO) driven fast sol–gel method. The cage -like spherical morphology is beneficial to efficiently trapping much incident light to enhance the PL of the phosphors. Being calcined at 1300 ℃, Sr_(2)MgAl_(21.978)O_(36):0.022Mn^(4+) only exhibits the internal quantum efficiency (IQE) of 24.91%. With the Mg^(2+)-Mn^(4+) codoping and Y^(3+)/Sr^(2+) substituting strategies, to fulfill charge balance and produce John-Teller distortion, IQE of Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) can be further improved up to 36.45%. The CIE color coordinates of Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) under near ultraviolet excitation can be stably fixed to (0.723, 0.227) at deep red region. It thus finds a potential application as pc-LED display with much broader color gamut than that of the NTSC standard. Therefore, Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) micron size spheres can be employed as promising red phosphors for high performance LED displays.展开更多
基金Project supported by the National Natural Science Foundation of China(52172008,51872255)the Key Research and Development Project of Zhejiang Province(2021C01174)。
文摘Eu^(2+)doped fluorosilicate glass-ceramics containing BaF_(2) nanocrystals have high potential as spectral conversion materials for organic solar cells.However,it is difficult to realize the efficient design of BaF_(2):Eu^(2+)doped fluorosilicate glass and to vividly observe the glass microstructure in experiment through traditional trial-and-error glass preparation method.BaF_(2):Eu^(2+)doped fluorosilicate glassceramics with high transparency,and high photoluminescence(PL)performance were predicted,designed and prepared via molecular dynamics(MD)simulation method.By MD simulation prediction,self-organized nanocrystallization was realized to inhibit the abnormal growth of nanocrystals due to[AlO_(4)]tetrahedra formed in the fluoride-oxide interface.The introduction of NaF reduces the effective phonon energy of the glass because Na+will prompt Al^(3+)to migrate from the fluoride phase to the silicate phase and interface.The local environment of Eu^(2+)is optimized by predicting the doping concentration of EuF_(3) and 2 mol%EuF3 is the best concentration in this work.Glass-ceramics sample GC2Eu as spectral conversion layer was successfully applied on organic solar cells to obtain more available visible phonons with a high photoelectric conversion efficiency(PCE).This work confirms the guidance of molecular dynamics simulation methods for fluorosilicate glasses design.
基金The Fund of the Cooperation Project of Southwest Technology and Engineering Research Institute under contract No.HDHDW5901010102the Fundamental Research Funds for the Central Universities under contract No.226-2023-00090.
文摘This study aims to systematically monitor the deposition rate of chloride ions at nine distinct locations on Zhairuoshan Island,situated in the East China Sea,over a 16-month period.The research investigates the effects of offshore distance,azimuth,seasonality,rainfall,and wind conditions on the chloride ion deposition rate.Additionally,an atmospheric corrosion test on Q235 steel is conducted at four representative sites on the island,with subsequent comparisons made to the chloride ion deposition rates observed.The findings indicate that wind energy has a more significant impact on the rate of chloride ion deposition.Furthermore,corrosion tests on Q235 steel demonstrate that the presence of chloride ions can accelerate the corrosion process.
基金Project supported by the National Natural Science Foundation of China(52172008,51872255)the National Key R&D Program of China(2022YFB3503700)。
文摘The rapid development of phosphor-converted white light emitting diodes(pc-WLEDs)requires new red phosphors with efficient and thermally stable luminescence for high-quality warm-white lighting.However,it is still a challenge to discover red phosphors with facile synthesis,high internal quantum efficiency(IQE),excellent thermal stability and high color purity.Herein,a novel red-emitting Eu^(3+)activated barium dialuminum digermanate(BaAl_(2)Ge_(3)O_(8),EAGO)phosphor showing strong red emission at 610 nm was prepared.The IQE is improved from 32.91%to 78.84%by employing a charge compensation strategy.The lithium-ion co-dop ed BAGO:Eu^(3+)phosphor exhibits a nearly twofold increase in integral photoluminescence(PL)intensity and the high color purity reaches 94.17%.Impressively,the PL intensity of the BAGO:Eu^(3+),Li^(+)phosphor drops by only 2.6%at 150℃of that at room temperature.Finally,the pc-WLED using the red BAGO:Eu^(3+),Li^(+)phosphor exhibits white light with the chromaticity coordinate of(0.3515,0.3495),a high color-rendering index of 92 and a low correlated color temperature of 4746 K.All these results manifest that BAGO:Eu^(3+),Li^(+)phosphor is a suitable red phosphor for nearultraviolet(NUV)chip-based pc-WLEDs.
基金Project supported by National Natural Science Foundation of China(51872255,51672243)。
文摘Significant developments have been made in the past few decades for lanthanide(Ln)ions doped fluorosilicate glass-ceramics(Flusi-GCs).As novel generation of luminescence materials with a wide range of applications,Flusi-GCs as a single host combine the advantages of glass and ceramics/crystals as well as fluorides and silicates.In this review,the chemical design principles and experimental procedures of Flusi-GCs are summarized in detail.Flusi-GCs are categorized as those containing PbxCd_(1-x)F_(2),RF_(3)(R=Y,La,Gd),MF_(2)(M=Ca,Sr,Ba),xMF_(2)-yRF_(3)(R=Y,La-Lu),mAF-nRF_(3)(A=Li,Na,K),KTF_(3)(T=Zn,Mn)and K2 SiF6 nanocrystals(NCs).Theoretical breakthroughs mainly by molecular dynamic(MD)simulation have been recapitulated as efficient routes for composition-design,nano-crystallization-prediction,and performance-optimization of Flusi-GCs containing target fluoride NCs.Essential research progresses pertaining photonic applications have been made in random lasers,communication amplifiers,optical fibers,spectral converters,white light-emitting-diodes(WLEDs),and thermal sensors.In the end,we propose three future research directions for Flusi-GCs.
基金Project supported by the National Natural Science Foundation of China (51872255,51672243)。
文摘With narrow red photoluminescence (PL) bands, tetravalent Mn^(4+) doped phosphors show promising prospect in commercial application to effectively expand color gamut of phosphor converted LED displays. Here, we report a type of Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) phosphors with regular cage-like micro-spherical morphologies. The micron size spherical precursors were synthesized with a propylene oxide (PO) driven fast sol–gel method. The cage -like spherical morphology is beneficial to efficiently trapping much incident light to enhance the PL of the phosphors. Being calcined at 1300 ℃, Sr_(2)MgAl_(21.978)O_(36):0.022Mn^(4+) only exhibits the internal quantum efficiency (IQE) of 24.91%. With the Mg^(2+)-Mn^(4+) codoping and Y^(3+)/Sr^(2+) substituting strategies, to fulfill charge balance and produce John-Teller distortion, IQE of Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) can be further improved up to 36.45%. The CIE color coordinates of Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) under near ultraviolet excitation can be stably fixed to (0.723, 0.227) at deep red region. It thus finds a potential application as pc-LED display with much broader color gamut than that of the NTSC standard. Therefore, Sr_(2-z)Mg_(1+y)Y_(z)Al_(22-x)O_(36):xMn^(4+) micron size spheres can be employed as promising red phosphors for high performance LED displays.
