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
Herein,we report the synthesis and third-order nonlinear optical(NLO)properties of a novel cage-based 2D metal-organic framework constructed from Ti_(4)L_(6)(L4-=embonate)cage combined with Mg^(2+)and tris[4-(1H-imida...Herein,we report the synthesis and third-order nonlinear optical(NLO)properties of a novel cage-based 2D metal-organic framework constructed from Ti_(4)L_(6)(L4-=embonate)cage combined with Mg^(2+)and tris[4-(1H-imidazol-1-yl)phenyl]amine(tipa)ligand,whose molecular formula is(Me_(2)CH_(2))_(2)[Mg_(3)(Ti_(4)L_(6))(tipa)(H_(2)O)_(12)](PTC‑378).The Ti_(4)L_(6)tetrahedral cages serve as robust building units,while the Mg^(2+)ions and tipa ligands provide structural stability and tunable optical properties.The resulting PTC‑378 film exhibited intriguing third-order NLO property,which was systematically investigated using Z-scan techniques.Our results demonstrate that the synergistic interaction between Ti_(4)L_(6)cages andπ-conjugated ligands significantly enhances the NLO performance of the materials.CCDC:2453909.展开更多
In the paper,we report a highly robust and porous bimetallic Ti-MOF(designated Mg_(2)Ti-ABTC)by utiliz-ing a trinuclear[Mg_(2)TiO(COO)_(6)]cluster and a tetradentate H_(4)ABTC(3,3′,5,5′-azobenzene tetracarboxylic ac...In the paper,we report a highly robust and porous bimetallic Ti-MOF(designated Mg_(2)Ti-ABTC)by utiliz-ing a trinuclear[Mg_(2)TiO(COO)_(6)]cluster and a tetradentate H_(4)ABTC(3,3′,5,5′-azobenzene tetracarboxylic acid)ligand.Mg_(2)Ti-ABTC exhibited permanent porosity for N_(2),CO_(2),CH_(4),C_(2)H_(2),C_(2)H_(4),and C_(2)H_(6)gas adsorption.Further-more,Mg_(2)Ti-ABTC exhibited outstanding photocatalytic activity in the oxidation of aromatic sulfides to the corre-sponding sulfoxides under ambient air conditions.Mechanism studies reveal that photoinduced holes(h^(+)),the super-oxide radical(·O_(2)^(-)),and singlet oxygen(^(1)O_(2))are pivotal species involved in the photocatalytic oxidation reaction.展开更多
Using MgSO4 and NaOH solutions as starting materials, the whisker of 5Mg(OH)2·MgSO4·2H2O has been prepared by hydrothermal method at 160℃ for different time. The whisker was separated, washed by water, etha...Using MgSO4 and NaOH solutions as starting materials, the whisker of 5Mg(OH)2·MgSO4·2H2O has been prepared by hydrothermal method at 160℃ for different time. The whisker was separated, washed by water, ethanol and ether,and characterized by chemical analysis, XRD, IR and microphotography. The growth time of whisker would affect its morphology.展开更多
: The structures of Mg-Al-CO3 and Zn-Al-CO3 hydrotalcites have been studied by means of XRD,IR and TG-DTA.Although both have the same crystal structures,their thermal stabilities are quite different.During the therma...: The structures of Mg-Al-CO3 and Zn-Al-CO3 hydrotalcites have been studied by means of XRD,IR and TG-DTA.Although both have the same crystal structures,their thermal stabilities are quite different.During the thermal decomposition process,Mg-Al-CO3 hydrotalcite exhibits two steps- desorption of interlayer water occurs at 200℃ ,followed by dehydroxylation of the brucite-like layers and loss of carbonate at 400℃ ,Zn-Al-CO3 hydrotalcite decomposes in one step-the desorption of interlayer water, structural water and carbon dioxide occurred at the same time at 200℃ . The results of a theoretical study indicate that the bond strengths of OH-CO3-OH and OH-H2O-CO3-OH in Mg-Al-CO3 hydrotalcite are stronger than those in Zn-Al-CO3 hydrotalcite.It has been shown that the thermal stability of Mg-Al-CO3 hydrotalcite is higher than that of Zn-Al-CO3 hydrotalcite.展开更多
The precursor for nano-sized magnesia was prepared by using Mg(NO3)2·6H2O as raw material, the hydrolysis product of hexamethylene tetramine as precipitating reagent and water as reaction media, and with the poly...The precursor for nano-sized magnesia was prepared by using Mg(NO3)2·6H2O as raw material, the hydrolysis product of hexamethylene tetramine as precipitating reagent and water as reaction media, and with the polymer (PEG) and DMF as protection reagents for particles. Nano-sized magnesia was prepared by calcining the precursor at 873 K after being dehydrated by freeze centrifugation and vacuum drying at a constant temperature. The formation process and structure of MgO nanocrystallites were investigated by means of TG-DTA, FTIR, TEM, XRD and BET. The results showed that the crystal belonged to cubic system and the average size was 3.1 nm and the specific surface area was 229 m2·g-1.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Herein,we report the synthesis and third-order nonlinear optical(NLO)properties of a novel cage-based 2D metal-organic framework constructed from Ti_(4)L_(6)(L4-=embonate)cage combined with Mg^(2+)and tris[4-(1H-imidazol-1-yl)phenyl]amine(tipa)ligand,whose molecular formula is(Me_(2)CH_(2))_(2)[Mg_(3)(Ti_(4)L_(6))(tipa)(H_(2)O)_(12)](PTC‑378).The Ti_(4)L_(6)tetrahedral cages serve as robust building units,while the Mg^(2+)ions and tipa ligands provide structural stability and tunable optical properties.The resulting PTC‑378 film exhibited intriguing third-order NLO property,which was systematically investigated using Z-scan techniques.Our results demonstrate that the synergistic interaction between Ti_(4)L_(6)cages andπ-conjugated ligands significantly enhances the NLO performance of the materials.CCDC:2453909.
文摘In the paper,we report a highly robust and porous bimetallic Ti-MOF(designated Mg_(2)Ti-ABTC)by utiliz-ing a trinuclear[Mg_(2)TiO(COO)_(6)]cluster and a tetradentate H_(4)ABTC(3,3′,5,5′-azobenzene tetracarboxylic acid)ligand.Mg_(2)Ti-ABTC exhibited permanent porosity for N_(2),CO_(2),CH_(4),C_(2)H_(2),C_(2)H_(4),and C_(2)H_(6)gas adsorption.Further-more,Mg_(2)Ti-ABTC exhibited outstanding photocatalytic activity in the oxidation of aromatic sulfides to the corre-sponding sulfoxides under ambient air conditions.Mechanism studies reveal that photoinduced holes(h^(+)),the super-oxide radical(·O_(2)^(-)),and singlet oxygen(^(1)O_(2))are pivotal species involved in the photocatalytic oxidation reaction.
文摘Using MgSO4 and NaOH solutions as starting materials, the whisker of 5Mg(OH)2·MgSO4·2H2O has been prepared by hydrothermal method at 160℃ for different time. The whisker was separated, washed by water, ethanol and ether,and characterized by chemical analysis, XRD, IR and microphotography. The growth time of whisker would affect its morphology.
文摘: The structures of Mg-Al-CO3 and Zn-Al-CO3 hydrotalcites have been studied by means of XRD,IR and TG-DTA.Although both have the same crystal structures,their thermal stabilities are quite different.During the thermal decomposition process,Mg-Al-CO3 hydrotalcite exhibits two steps- desorption of interlayer water occurs at 200℃ ,followed by dehydroxylation of the brucite-like layers and loss of carbonate at 400℃ ,Zn-Al-CO3 hydrotalcite decomposes in one step-the desorption of interlayer water, structural water and carbon dioxide occurred at the same time at 200℃ . The results of a theoretical study indicate that the bond strengths of OH-CO3-OH and OH-H2O-CO3-OH in Mg-Al-CO3 hydrotalcite are stronger than those in Zn-Al-CO3 hydrotalcite.It has been shown that the thermal stability of Mg-Al-CO3 hydrotalcite is higher than that of Zn-Al-CO3 hydrotalcite.
文摘The precursor for nano-sized magnesia was prepared by using Mg(NO3)2·6H2O as raw material, the hydrolysis product of hexamethylene tetramine as precipitating reagent and water as reaction media, and with the polymer (PEG) and DMF as protection reagents for particles. Nano-sized magnesia was prepared by calcining the precursor at 873 K after being dehydrated by freeze centrifugation and vacuum drying at a constant temperature. The formation process and structure of MgO nanocrystallites were investigated by means of TG-DTA, FTIR, TEM, XRD and BET. The results showed that the crystal belonged to cubic system and the average size was 3.1 nm and the specific surface area was 229 m2·g-1.