The reaction of Mg^(2+)and 5-{1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl}terephthalic acid(H_(2)L)leads to two metal-organic frameworks,[Mg(L)(DMF)_(2)(H_(2)O)_(2)]_(2)·5DMF·2H_(2)O(1)with a 1D structure and...The reaction of Mg^(2+)and 5-{1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl}terephthalic acid(H_(2)L)leads to two metal-organic frameworks,[Mg(L)(DMF)_(2)(H_(2)O)_(2)]_(2)·5DMF·2H_(2)O(1)with a 1D structure and[Mg_(2)(L)_(2)(DMSO)_(3)(H_(2)O)](2)with a 2D(4,4)-net structure.Interestingly,the two compounds exhibit distinct luminescent responses to external mechanical stimuli.1 exhibited exceptional resistance mechanical chromic luminescence(RMCL),which can be attributed to the predominant hydrogen bonds and the presence of high-boiling-point solvent molecules within its structure.2 had a reversible MCL property,which can be attributed to the dominantπ-πweak interactions,coupled with the reversible destruction/restoration of its crystallinity under grinding/fumigation.CCDC:2410963,1;2410964,2.展开更多
One Yb(Ⅲ)-based coordination polymer,{[Yb(H_(2)dhtp)1.5(H_(2)O)_(4)]·3H_(2)O}n(1)(H_(4)dhtp=2,5-dihydroxytere-phthalic acid),was fabricated and structurally characterized by single-crystal X-ray diffraction,IR,p...One Yb(Ⅲ)-based coordination polymer,{[Yb(H_(2)dhtp)1.5(H_(2)O)_(4)]·3H_(2)O}n(1)(H_(4)dhtp=2,5-dihydroxytere-phthalic acid),was fabricated and structurally characterized by single-crystal X-ray diffraction,IR,powder X-ray diffraction,X-ray diffraction,and elemental analysis.Complex 1 displays a 1D chain structure,and belongs to P1 group.The solid-state luminescent spectrum of 1 showed an emission band with the maximum at 508 nm(λex=408 nm).It exhibited the emission characteristic of the H_(4)dhtp ligand.The fluorescence of 1 in water displayed the stron-gest intensity.In detecting various metal ions,adding Zr^(4+)led to a blue shift in fluorescence,accompanied by an increase in intensity,whereas the presence of Fe^(3+)resulted in a decrease in luminescence.The changes observed in the IR spectrum indicate an interaction between Fe^(3+)/Zr^(4+)and complex 1,resulting in the variation of luminescence properties.展开更多
Broadband near-infrared(NIR)luminescent materials have shown great promise in applications such as optical communication,biomedicine,and optoelectronic devices.However,the current research is focused on phos⁃phors and...Broadband near-infrared(NIR)luminescent materials have shown great promise in applications such as optical communication,biomedicine,and optoelectronic devices.However,the current research is focused on phos⁃phors and glasses,and it is important to develop broadband NIR luminescent nanomaterials.Here,we report an erbi⁃um-sensitized core-shell nanocrystal design for broadband NIR emission.Based on the structural design with suitable dopings of Tm^(3+)and Ho^(3+),the broadband NIR emission covering 1.5-2.1μm region is achieved under 980 nm and 808 nm excitations.Moreover,the emission intensity is further enhanced by introducing Yb^(3+)and Nd^(3+)into the sam⁃ple,respectively,and the energy transfer processes between them are systematically discussed.Our results present a novel approach for developing broadband NIR luminescent materials and devices.展开更多
Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)...Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)O)6][Zn_(2)(mbtx)_(2)(btc)_(2)(H_(2)O)_(4)]·2H_(2)O}n(4)(mbtx=1,3-bis(4H-1,2,4-triazole)benzene,4OHphCOO-=p-hydroxybenzoate,1,4-bdc2-=1,4-benzenedicarboxylate,5NO_(2)-bdc2-=5-nitro-isophthalate,btc3-=1,3,5-benzenetricarboxylate),were synthesized under room temperature condition and characterized by single-crystal X-ray diffraction,elemental analyses,and powder X-ray diffraction.Single-crystal X-ray structural analysis shows that complexes 1 and 3 are 2D networks.In 1,the adjacent 2D networks are linked to a 3D network byπ-πstacking interaction.2 and 4 exhibit 1D chains,and the 1D chains are connected into a 3D network byπ-πstacking interaction and intermolecular hydrogen bond.Luminescence and thermogravimetric analysis of the four complexes were discussed.CCDC:2416406,1;2416407,2;2416408,3;2416409,4.展开更多
ZnO：La3＋,Li＋ nanoparticles were successfully prepared by co-precipitation, citric acid-assisted co-precipitation, co-precipitation combined solid-state reaction and thermal decomposition method. X-ray diffraction ...ZnO：La3＋,Li＋ nanoparticles were successfully prepared by co-precipitation, citric acid-assisted co-precipitation, co-precipitation combined solid-state reaction and thermal decomposition method. X-ray diffraction （XRD）, scanning electron microscopy （SEM） and luminescence spectrophotometry were employed to characterize the crystal phases, particle sizes and luminescence properties of the as-prepared nanopowders. The results indicate that all the prepared samples crystallize in a hexagonal wurtzite structure. The ZnO：La3＋,Li＋ prepared by citric acid-assisted co-precipitation method has a particle size of about 80 nm, which is the smallest among all the samples. Fluorescence （FL） spectra of all samples exhibit three typical emissions： a violet one centered at around 400 nm, blue around 450 nm and 466 rim, and weak green near 520 nm. But the samples prepared by co-precipitation method show a strong and wide green light emission located at about 500 nm. The ZnO：La3＋,Li＋ nanoparticles synthesized by the co-precipitation method demonstrate relatively the strongest emission intensity.展开更多
In this paper, we have succesfully prepared the sample of BaFCl: Eu<sup>2+</sup>thin film using the vacuum thermal evaporation method and first studied photostimulated luminescence on BaFCl: Eu<sup>2...In this paper, we have succesfully prepared the sample of BaFCl: Eu<sup>2+</sup>thin film using the vacuum thermal evaporation method and first studied photostimulated luminescence on BaFCl: Eu<sup>2+</sup>thin film.展开更多
Rare-earth doped inorganic ferroelectrics are considered as novel photochromic materials,with potential applications for optical switch and information storage(K0.5Na0.5)1–xEuxNbO3(KNN:xEu)ceramics were prepared by h...Rare-earth doped inorganic ferroelectrics are considered as novel photochromic materials,with potential applications for optical switch and information storage(K0.5Na0.5)1–xEuxNbO3(KNN:xEu)ceramics were prepared by high temperature calcination,with precursor powder obtained by hydrothermal method.Strong red emission at 615 nm was observed which corresponds to the 5D0→7F2 transition of Eu3+under excitation of 465 nm.Under UV light irradiation for 3 min,the color of the ceramics turned from milky white to dark gray.The colored samples returned to the original color when heated at 200℃for 10 min,showing strong photochromic behavior.Meanwhile,the luminescence intensity of Eu3+can be tuned without obvious degradation by alternating UV light and heat stimulus.Upon UV light irradiation,large luminescence modulation ratio(ΔRt)up to 83.9%was achieved for KNN:0.06Eu,indicating good luminescence switching behavior.A possible mechanism for non-radiative energy transfer from the luminescent center to the color center was proposed according to their luminescent behavior.展开更多
文摘The reaction of Mg^(2+)and 5-{1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl}terephthalic acid(H_(2)L)leads to two metal-organic frameworks,[Mg(L)(DMF)_(2)(H_(2)O)_(2)]_(2)·5DMF·2H_(2)O(1)with a 1D structure and[Mg_(2)(L)_(2)(DMSO)_(3)(H_(2)O)](2)with a 2D(4,4)-net structure.Interestingly,the two compounds exhibit distinct luminescent responses to external mechanical stimuli.1 exhibited exceptional resistance mechanical chromic luminescence(RMCL),which can be attributed to the predominant hydrogen bonds and the presence of high-boiling-point solvent molecules within its structure.2 had a reversible MCL property,which can be attributed to the dominantπ-πweak interactions,coupled with the reversible destruction/restoration of its crystallinity under grinding/fumigation.CCDC:2410963,1;2410964,2.
文摘One Yb(Ⅲ)-based coordination polymer,{[Yb(H_(2)dhtp)1.5(H_(2)O)_(4)]·3H_(2)O}n(1)(H_(4)dhtp=2,5-dihydroxytere-phthalic acid),was fabricated and structurally characterized by single-crystal X-ray diffraction,IR,powder X-ray diffraction,X-ray diffraction,and elemental analysis.Complex 1 displays a 1D chain structure,and belongs to P1 group.The solid-state luminescent spectrum of 1 showed an emission band with the maximum at 508 nm(λex=408 nm).It exhibited the emission characteristic of the H_(4)dhtp ligand.The fluorescence of 1 in water displayed the stron-gest intensity.In detecting various metal ions,adding Zr^(4+)led to a blue shift in fluorescence,accompanied by an increase in intensity,whereas the presence of Fe^(3+)resulted in a decrease in luminescence.The changes observed in the IR spectrum indicate an interaction between Fe^(3+)/Zr^(4+)and complex 1,resulting in the variation of luminescence properties.
文摘Broadband near-infrared(NIR)luminescent materials have shown great promise in applications such as optical communication,biomedicine,and optoelectronic devices.However,the current research is focused on phos⁃phors and glasses,and it is important to develop broadband NIR luminescent nanomaterials.Here,we report an erbi⁃um-sensitized core-shell nanocrystal design for broadband NIR emission.Based on the structural design with suitable dopings of Tm^(3+)and Ho^(3+),the broadband NIR emission covering 1.5-2.1μm region is achieved under 980 nm and 808 nm excitations.Moreover,the emission intensity is further enhanced by introducing Yb^(3+)and Nd^(3+)into the sam⁃ple,respectively,and the energy transfer processes between them are systematically discussed.Our results present a novel approach for developing broadband NIR luminescent materials and devices.
文摘Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)O)6][Zn_(2)(mbtx)_(2)(btc)_(2)(H_(2)O)_(4)]·2H_(2)O}n(4)(mbtx=1,3-bis(4H-1,2,4-triazole)benzene,4OHphCOO-=p-hydroxybenzoate,1,4-bdc2-=1,4-benzenedicarboxylate,5NO_(2)-bdc2-=5-nitro-isophthalate,btc3-=1,3,5-benzenetricarboxylate),were synthesized under room temperature condition and characterized by single-crystal X-ray diffraction,elemental analyses,and powder X-ray diffraction.Single-crystal X-ray structural analysis shows that complexes 1 and 3 are 2D networks.In 1,the adjacent 2D networks are linked to a 3D network byπ-πstacking interaction.2 and 4 exhibit 1D chains,and the 1D chains are connected into a 3D network byπ-πstacking interaction and intermolecular hydrogen bond.Luminescence and thermogravimetric analysis of the four complexes were discussed.CCDC:2416406,1;2416407,2;2416408,3;2416409,4.
基金Project(50972166) supported by the National Natural Science Foundation of China
文摘ZnO：La3＋,Li＋ nanoparticles were successfully prepared by co-precipitation, citric acid-assisted co-precipitation, co-precipitation combined solid-state reaction and thermal decomposition method. X-ray diffraction （XRD）, scanning electron microscopy （SEM） and luminescence spectrophotometry were employed to characterize the crystal phases, particle sizes and luminescence properties of the as-prepared nanopowders. The results indicate that all the prepared samples crystallize in a hexagonal wurtzite structure. The ZnO：La3＋,Li＋ prepared by citric acid-assisted co-precipitation method has a particle size of about 80 nm, which is the smallest among all the samples. Fluorescence （FL） spectra of all samples exhibit three typical emissions： a violet one centered at around 400 nm, blue around 450 nm and 466 rim, and weak green near 520 nm. But the samples prepared by co-precipitation method show a strong and wide green light emission located at about 500 nm. The ZnO：La3＋,Li＋ nanoparticles synthesized by the co-precipitation method demonstrate relatively the strongest emission intensity.
基金Project Supported by the National Science Foundation of China.
文摘In this paper, we have succesfully prepared the sample of BaFCl: Eu<sup>2+</sup>thin film using the vacuum thermal evaporation method and first studied photostimulated luminescence on BaFCl: Eu<sup>2+</sup>thin film.
基金National Natural Science Foundation of China(61605116,51972213)Science and Technology Commission of Shanghai Municipality(15ZR1440600,15520503400)。
文摘Rare-earth doped inorganic ferroelectrics are considered as novel photochromic materials,with potential applications for optical switch and information storage(K0.5Na0.5)1–xEuxNbO3(KNN:xEu)ceramics were prepared by high temperature calcination,with precursor powder obtained by hydrothermal method.Strong red emission at 615 nm was observed which corresponds to the 5D0→7F2 transition of Eu3+under excitation of 465 nm.Under UV light irradiation for 3 min,the color of the ceramics turned from milky white to dark gray.The colored samples returned to the original color when heated at 200℃for 10 min,showing strong photochromic behavior.Meanwhile,the luminescence intensity of Eu3+can be tuned without obvious degradation by alternating UV light and heat stimulus.Upon UV light irradiation,large luminescence modulation ratio(ΔRt)up to 83.9%was achieved for KNN:0.06Eu,indicating good luminescence switching behavior.A possible mechanism for non-radiative energy transfer from the luminescent center to the color center was proposed according to their luminescent behavior.
