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2016 Volume 32 Issue 9
2016, 32(9): 1495-1502
doi: 10.11862/CJIC.2016.173
Abstract:
A graphene-based anode material is demonstrated: N-doped carbon-encapsulated cobalt nanoparticles on N-doped graphene nanosheets (NC@Co@NG), in which cobalt nanoparticles encapsulated by N-doped carbon layer are highly dispersed on the N-doped graphene nanosheets, forming multiple sites for electrical conductivity enhancement and lithium insertion. When used as anode materials in lithium-ion batteries, the nanocomposites exhibit outstanding electrochemical performance, including a considerably large reversible capacity of 950.1 mAh·g-1 after 200 cycles at a current density of 100 mA·g-1 and Coulombic efficiency of 98%.
A graphene-based anode material is demonstrated: N-doped carbon-encapsulated cobalt nanoparticles on N-doped graphene nanosheets (NC@Co@NG), in which cobalt nanoparticles encapsulated by N-doped carbon layer are highly dispersed on the N-doped graphene nanosheets, forming multiple sites for electrical conductivity enhancement and lithium insertion. When used as anode materials in lithium-ion batteries, the nanocomposites exhibit outstanding electrochemical performance, including a considerably large reversible capacity of 950.1 mAh·g-1 after 200 cycles at a current density of 100 mA·g-1 and Coulombic efficiency of 98%.
2016, 32(9): 1585-1595
doi: 10.11862/CJIC.2016.199
Abstract:
A series of chiral MnⅢ(Salen) catalysts that were axially supported onto zirconium poly (styrene-isopropenyl phosphonate)-phosphate(ZPS-IPPA) through phenoxyl linkers have been developed, and their performance as catalysts for the epoxidation of styrene has been evaluated. The catalytic results indicated that the substituents at the o-positions of the phenoxyl linkers have a critical impact on the catalytic activity, in that the o-t-Bu group provided higher levels of enantioselectivity than the o-H and o-CH3 groups of the phenoxyl linker. At the same time, two linkages (-NH-C6H4-NH-, -O-C6H4-O-) with similar length were compared, the results demonstrated that the linkage of -O-C6H4-O- have more positive effect than the use of -NH-C6H4-NH-in absence of NMO in m-CPBA oxidant systems on the catalytic efficiency. Furthermore, the catalysts could be recycled up to five times without any significant reduction in their catalytic activity or enantioselectivity.
A series of chiral MnⅢ(Salen) catalysts that were axially supported onto zirconium poly (styrene-isopropenyl phosphonate)-phosphate(ZPS-IPPA) through phenoxyl linkers have been developed, and their performance as catalysts for the epoxidation of styrene has been evaluated. The catalytic results indicated that the substituents at the o-positions of the phenoxyl linkers have a critical impact on the catalytic activity, in that the o-t-Bu group provided higher levels of enantioselectivity than the o-H and o-CH3 groups of the phenoxyl linker. At the same time, two linkages (-NH-C6H4-NH-, -O-C6H4-O-) with similar length were compared, the results demonstrated that the linkage of -O-C6H4-O- have more positive effect than the use of -NH-C6H4-NH-in absence of NMO in m-CPBA oxidant systems on the catalytic efficiency. Furthermore, the catalysts could be recycled up to five times without any significant reduction in their catalytic activity or enantioselectivity.
2016, 32(9): 1596-1602
doi: 10.11862/CJIC.2016.180
Abstract:
Two new mononuclear dioxomolybdenum(Ⅵ) complexes with general formula [MoO2L(MeOH)], where L1 and L2 are the dianionic form of N'-(3-bromo-2-hydroxybenzylidene)-3, 5-dimethoxybenzohydrazide and N'-(5-bromo-2-hydroxybenzylidene)isonicotinohydrazide, respectively, were prepared and structurally characterized by physico-chemical, spectroscopic methods and single crystal X-ray determination. The crystal of complex 1 crystallizes in monoclinic space group P21/n, with a=0.848 98(3) nm, b=2.275 4(1) nm, c=1.069 82(5) nm, β=109.108(1)°, V=1.952 8(1) nm3, Z=4, R1=0.036 7, wR2=0.084 0, S=1.027. The crystal of complex 2 crystallizes in triclinic space group P1, with a=0.655 05(9) nm, b=1.076 63(7) nm, c=1.303 3(1) nm, α=67.383(2)°, β=84.264(1)°, γ=76.195(2)°, V=0.823 9(1) nm3, Z=2, R1=0.071 3, wR2=0.151 0, S=1.004. X-ray analysis indicates that the Mo atom in each complex is in an octahedral coordination environment, constructed by two oxo groups and NO2 donor set of the hydrazone ligand, as well as a methanol O atom. The catalytic property of the complexes indicates that they are efficient catalysts for the oxidation of olefins. CCDC: 1476621, 1; 1476622, 2.
Two new mononuclear dioxomolybdenum(Ⅵ) complexes with general formula [MoO2L(MeOH)], where L1 and L2 are the dianionic form of N'-(3-bromo-2-hydroxybenzylidene)-3, 5-dimethoxybenzohydrazide and N'-(5-bromo-2-hydroxybenzylidene)isonicotinohydrazide, respectively, were prepared and structurally characterized by physico-chemical, spectroscopic methods and single crystal X-ray determination. The crystal of complex 1 crystallizes in monoclinic space group P21/n, with a=0.848 98(3) nm, b=2.275 4(1) nm, c=1.069 82(5) nm, β=109.108(1)°, V=1.952 8(1) nm3, Z=4, R1=0.036 7, wR2=0.084 0, S=1.027. The crystal of complex 2 crystallizes in triclinic space group P1, with a=0.655 05(9) nm, b=1.076 63(7) nm, c=1.303 3(1) nm, α=67.383(2)°, β=84.264(1)°, γ=76.195(2)°, V=0.823 9(1) nm3, Z=2, R1=0.071 3, wR2=0.151 0, S=1.004. X-ray analysis indicates that the Mo atom in each complex is in an octahedral coordination environment, constructed by two oxo groups and NO2 donor set of the hydrazone ligand, as well as a methanol O atom. The catalytic property of the complexes indicates that they are efficient catalysts for the oxidation of olefins. CCDC: 1476621, 1; 1476622, 2.
Single Adsorption Capacity of Methylene Blue on ZnO/C Nanosphere:Equilibrium, Kinetics and Mechanism
2016, 32(9): 1603-1610
doi: 10.11862/CJIC.2016.213
Abstract:
Carbon-inorganic ZnO/C nanosphere hybrid materials was simply prepared by arc discharge method. The hybrid materials was characterized by field-emission scanning electron microscopy(FE-SEM), X-ray diffraction(XRD) and BET surface area. The adsorption property of methylene blue (MB) on ZnO/C nanosphere was carried out under the dark conditions. Results showed that the adsorption uptake increased as the increase of initial MB concentration and contact time, and the process reached equilibrium at the time of 150 min. Langmuir, Freundlich and Temkin isotherm were employed to describe the adsorption equilibrium. The isotherm study indicated that Langmuir model fitted well with the adsorption data, and a monolayer saturation capacity of 188.68 mg·g-1 was obtained. Kinetic models, Webbers pore diffusion model and Boyds equation were applied for the experimental data to study the adsorption mechanism. Results shows that the kinetics followed the pseudo-second order kinetic model and the adsorption process was controlled by film diffusion as opposed intraparticle diffusion mechanism. The results indicate that the ZnO/C nanosphere is also a promising material for the adsorption of MB from aqueous solutions.
Carbon-inorganic ZnO/C nanosphere hybrid materials was simply prepared by arc discharge method. The hybrid materials was characterized by field-emission scanning electron microscopy(FE-SEM), X-ray diffraction(XRD) and BET surface area. The adsorption property of methylene blue (MB) on ZnO/C nanosphere was carried out under the dark conditions. Results showed that the adsorption uptake increased as the increase of initial MB concentration and contact time, and the process reached equilibrium at the time of 150 min. Langmuir, Freundlich and Temkin isotherm were employed to describe the adsorption equilibrium. The isotherm study indicated that Langmuir model fitted well with the adsorption data, and a monolayer saturation capacity of 188.68 mg·g-1 was obtained. Kinetic models, Webbers pore diffusion model and Boyds equation were applied for the experimental data to study the adsorption mechanism. Results shows that the kinetics followed the pseudo-second order kinetic model and the adsorption process was controlled by film diffusion as opposed intraparticle diffusion mechanism. The results indicate that the ZnO/C nanosphere is also a promising material for the adsorption of MB from aqueous solutions.
2016, 32(9): 1611-1618
doi: 10.11862/CJIC.2016.203
Abstract:
Two coordination compounds, namely [Mn2(Hbtc)2(phen)4]·5H2O (1) and [Ni2(Hbtc)2(phen)4]·2H3btc·4H2O (2) have been constructed hydrothermally using H3btc(H3btc=biphenyl-2, 4, 4′-tricarboxylic acid), phen (phen =phenanthroline), MnCl2·4H2O and NiCl2·6H2O. Both compounds crystallize in the triclinic system, space group P1. The compounds possess the dinuclear structures, which are further extended into the 3D supramolecular frameworks through O-H…O hydrogen bonding. Magnetic studies for compounds 1 and 2 show a weak antiferro-magnetic coupling between the neighbouring metal centers, with J=-3.82 cm-1 (1) and -2.35 cm-1 (2). CCDC: 1456513, 1; 1456514, 2.
Two coordination compounds, namely [Mn2(Hbtc)2(phen)4]·5H2O (1) and [Ni2(Hbtc)2(phen)4]·2H3btc·4H2O (2) have been constructed hydrothermally using H3btc(H3btc=biphenyl-2, 4, 4′-tricarboxylic acid), phen (phen =phenanthroline), MnCl2·4H2O and NiCl2·6H2O. Both compounds crystallize in the triclinic system, space group P1. The compounds possess the dinuclear structures, which are further extended into the 3D supramolecular frameworks through O-H…O hydrogen bonding. Magnetic studies for compounds 1 and 2 show a weak antiferro-magnetic coupling between the neighbouring metal centers, with J=-3.82 cm-1 (1) and -2.35 cm-1 (2). CCDC: 1456513, 1; 1456514, 2.
2016, 32(9): 1619-1628
doi: 10.11862/CJIC.2016.200
Abstract:
Iron-oxide-modified vermiculite (Verm-Fex, x=5, 10, 20) was prepared by a co-precipitation procedure. The surface properties and fluoride adsorption of pure vermiculite (Verm) and Verm-Fex were investigated. Compared to Verm, the d(002) spacing of Verm in Verm-Fex increases slightly, and the pore volumes, different surface areas and surface fractal dimension of Verm-Fex increase with increasing the Fe contents. The increased magnitude of the micropore volume and external surface area of Verm-Fex is more significant. The isoelectric point (IEP) of the samples increases in the order of Verm < Verm-Fe5 < Verm-Fe10 < Verm-Fe20, and the ζ potential at pH 5.0 of the four samples is -16.4, -6.1, 10.5, and 28.4 mV, respectively. One-site Langmuir model was used to describe the fluoride adsorption by the samples (R2=0.973~0.995), and the determination coefficient (R2) for Verm is the highest. The R2 fitted from two-site model for Verm-Fex(x=5, 10, 20) is higher than that from one-site model, indicating that the adsorption data of Verm-Fex can be fitted by two-site model well. The R2 fitted from Freundlich model of the samples is lying in the range of 0.835~0.937 and follows the sequence of Verm < Verm-Fe5 < Verm-Fe10 < Verm-Fe20. This indicates that Verm-Fex possesses the heterogeneous surfaces with different reactive sites. When pH=5.0, the adsorption capacities (qmax) of Verm, Verm-Fe5, Verm-Fe10 and Verm-Fe20 are 3.18, 6.76, 9.27 and 12.43 mg·g-1, respectively. Compared to Verm, Verm-Fex with a high Fe content has a higher adsorption capacity for fluoride in solutions.
Iron-oxide-modified vermiculite (Verm-Fex, x=5, 10, 20) was prepared by a co-precipitation procedure. The surface properties and fluoride adsorption of pure vermiculite (Verm) and Verm-Fex were investigated. Compared to Verm, the d(002) spacing of Verm in Verm-Fex increases slightly, and the pore volumes, different surface areas and surface fractal dimension of Verm-Fex increase with increasing the Fe contents. The increased magnitude of the micropore volume and external surface area of Verm-Fex is more significant. The isoelectric point (IEP) of the samples increases in the order of Verm < Verm-Fe5 < Verm-Fe10 < Verm-Fe20, and the ζ potential at pH 5.0 of the four samples is -16.4, -6.1, 10.5, and 28.4 mV, respectively. One-site Langmuir model was used to describe the fluoride adsorption by the samples (R2=0.973~0.995), and the determination coefficient (R2) for Verm is the highest. The R2 fitted from two-site model for Verm-Fex(x=5, 10, 20) is higher than that from one-site model, indicating that the adsorption data of Verm-Fex can be fitted by two-site model well. The R2 fitted from Freundlich model of the samples is lying in the range of 0.835~0.937 and follows the sequence of Verm < Verm-Fe5 < Verm-Fe10 < Verm-Fe20. This indicates that Verm-Fex possesses the heterogeneous surfaces with different reactive sites. When pH=5.0, the adsorption capacities (qmax) of Verm, Verm-Fe5, Verm-Fe10 and Verm-Fe20 are 3.18, 6.76, 9.27 and 12.43 mg·g-1, respectively. Compared to Verm, Verm-Fex with a high Fe content has a higher adsorption capacity for fluoride in solutions.
2016, 32(9): 1629-1636
doi: 10.11862/CJIC.2016.189
Abstract:
By utilizing two kinds of simply rigid organic ligands, two new polyoxometalates-modified transition metal compounds (POMs-TMC), [Cu(dmbipy)2(SiW12O40)][Cu(dmbipy)(H2O)3]·3H2O(1), and {(Hdmphen)2[Ag2(dmphen)2(SiW12O40)]}n(2) (dmbipy=4, 4′-dimethyl-2, 2′-bipyridine, dmphen=2, 9-dimethyl-1, 10-phenanthrolin), were synthesized through hydrothermal technique. In compound 1, there are two crystallographically independent Cu(Ⅱ) ions. They all exhibit penta-coordinated modes, with three water molecules embedding through Cu-O bonds. Different Cu(Ⅱ) subunits cross-link each other to build a 1D chain by hydrogen bonding interactions between coordinated water molecules and [SiW12O40]4- anions. Adjacent chains also pursue to construct a 2D layer by such hydrogen bonding. In compound 2, the Keggin anions are fused by Ag(Ⅱ) ions to form a 1D chain. The adjacent chains are further linked by π…π stacking and hydrogen bonding interactions. So, 2D polyoxometalates-modified organic layer is constructed. The main traits of compounds 1 and 2 are that these simply rigid organic ligands employ noncovalent interactions to form the 2D layer. CCDC: 1033952, 1; 1053009, 2.
By utilizing two kinds of simply rigid organic ligands, two new polyoxometalates-modified transition metal compounds (POMs-TMC), [Cu(dmbipy)2(SiW12O40)][Cu(dmbipy)(H2O)3]·3H2O(1), and {(Hdmphen)2[Ag2(dmphen)2(SiW12O40)]}n(2) (dmbipy=4, 4′-dimethyl-2, 2′-bipyridine, dmphen=2, 9-dimethyl-1, 10-phenanthrolin), were synthesized through hydrothermal technique. In compound 1, there are two crystallographically independent Cu(Ⅱ) ions. They all exhibit penta-coordinated modes, with three water molecules embedding through Cu-O bonds. Different Cu(Ⅱ) subunits cross-link each other to build a 1D chain by hydrogen bonding interactions between coordinated water molecules and [SiW12O40]4- anions. Adjacent chains also pursue to construct a 2D layer by such hydrogen bonding. In compound 2, the Keggin anions are fused by Ag(Ⅱ) ions to form a 1D chain. The adjacent chains are further linked by π…π stacking and hydrogen bonding interactions. So, 2D polyoxometalates-modified organic layer is constructed. The main traits of compounds 1 and 2 are that these simply rigid organic ligands employ noncovalent interactions to form the 2D layer. CCDC: 1033952, 1; 1053009, 2.
2016, 32(9): 1637-1646
doi: 10.11862/CJIC.2016.210
Abstract:
Two cyano-bridged Fe(Ⅲ)-Mn(Ⅱ) chains were synthesized via using bidentate ligands and cyanometallate building blocks with different steric hindrance. The magnetic interactions were adjusted by the structural distortions of the two compounds. Compound {[Fe(Ⅲ)(PzTp)(CN)3][Mn(Ⅱ)(5,5′-dmbpy)2]ClO4}n (1; PzTp=tetrakis(pyrazolyl)borate; 5,5′-dmbpy=5,5′-dimethyl-2, 2′-bipyridine) shows a 1D 2, 2-CC chain-like structure with a left-and right-handed helices chains and exhibits the ferrimagnetic behavior. Compound {[Fe(Ⅲ)(Tp*)(CN)3]2[Mn(Ⅱ)(dpqc)]·CH3OH·H2O}n (2; Tp*=hydridotris(3, 5-dimethylpyrazolyl)borate; dpqc=dipyrido[3, 2-a:2′, 3′-c]-(6, 7, 8, 9-tetrahydro)phenazine) has a novel 1D 4, 2-ribbon double chain-like structure with dominant antiferromagnetic interactions. CCDC: 1449127, 1; 1449128, 2.
Two cyano-bridged Fe(Ⅲ)-Mn(Ⅱ) chains were synthesized via using bidentate ligands and cyanometallate building blocks with different steric hindrance. The magnetic interactions were adjusted by the structural distortions of the two compounds. Compound {[Fe(Ⅲ)(PzTp)(CN)3][Mn(Ⅱ)(5,5′-dmbpy)2]ClO4}n (1; PzTp=tetrakis(pyrazolyl)borate; 5,5′-dmbpy=5,5′-dimethyl-2, 2′-bipyridine) shows a 1D 2, 2-CC chain-like structure with a left-and right-handed helices chains and exhibits the ferrimagnetic behavior. Compound {[Fe(Ⅲ)(Tp*)(CN)3]2[Mn(Ⅱ)(dpqc)]·CH3OH·H2O}n (2; Tp*=hydridotris(3, 5-dimethylpyrazolyl)borate; dpqc=dipyrido[3, 2-a:2′, 3′-c]-(6, 7, 8, 9-tetrahydro)phenazine) has a novel 1D 4, 2-ribbon double chain-like structure with dominant antiferromagnetic interactions. CCDC: 1449127, 1; 1449128, 2.
2016, 32(9): 1647-1652
doi: 10.11862/CJIC.2016.217
Abstract:
Two dinuclear lanthanide complexes [Ln2L(acac)4(CH3OH)]2·2CH2Cl2 (Ln=Ce (1), Eu (2)) prepared by salen-type (H2L=N, N'-bis(2-oxy-3-methoxybenzylidene)-1,2-phenylenediamine) ligand and Ln(acac)3·H2O (acac=acetylacetonate) were structurally characterized. X-ray crystallographic analysis reveals that the two Ln(Ⅲ) ions adopt same coordination environments that octa-coordinated Ln(Ⅲ) atoms form square antiprism geometry. Luminescent analysis reveals the Eu(Ⅲ) ion and ligand-centered co-luminescence for complex 2, which is attributed to the incomplete energy transfer from the triplet state of H2L to the resonance energy level of the corresponding Eu(Ⅲ) ion. CCDC: 1482355, 1; 1449142, 2.
Two dinuclear lanthanide complexes [Ln2L(acac)4(CH3OH)]2·2CH2Cl2 (Ln=Ce (1), Eu (2)) prepared by salen-type (H2L=N, N'-bis(2-oxy-3-methoxybenzylidene)-1,2-phenylenediamine) ligand and Ln(acac)3·H2O (acac=acetylacetonate) were structurally characterized. X-ray crystallographic analysis reveals that the two Ln(Ⅲ) ions adopt same coordination environments that octa-coordinated Ln(Ⅲ) atoms form square antiprism geometry. Luminescent analysis reveals the Eu(Ⅲ) ion and ligand-centered co-luminescence for complex 2, which is attributed to the incomplete energy transfer from the triplet state of H2L to the resonance energy level of the corresponding Eu(Ⅲ) ion. CCDC: 1482355, 1; 1449142, 2.
2016, 32(9): 1653-1658
doi: 10.11862/CJIC.2016.204
Abstract:
Five complexes, [CuLCl2]·CH3COCH3 (1), [ZnLCl2]·CH3COCH3 (2), [ZnL(NO3)2]·0.5CH3COCH3 (3), [AgL2]ClO4 (4) and [AgL2]BF4 (5) (L=2-(5-chloroquinolin-8-yloxy)-1-(pyrrolidin-1-yl)ethanone), were synthesized and characterized by X-ray diffraction. Complexes 1 and 2 are isostructural, and in each of them the five-coordinated metal ion is in a distorted tetragonal pyramid with a NO2 donor set from one ligand L and two chloride anions. However, the Zn(Ⅱ) ion in complex 3 is coordinated with one tridentate ligand L, one monodentate and one bidentate nitrate anions, giving a distorted octahedral coordination geometry. The structures of 1~3 are quite similar as those of the acetonitrile solvates derived from the same ligand L and metal salts. By contrast, the ratio of the metal ion and ligand L is 1:2 in complexes 4 and 5, the central Ag(Ⅰ) ion in each complex is six-coordinated with two independent ligands with N2O donor set, thus possesses a distorted octahedral coordination geometry. In CH3CN solution, the emission spectra of complexes 1, 3, 4 and 5 exhibit similar peak at 410 nm as the ligand L. However, the emission band of complex 3 red-shifts to 430 nm because of energy transferring from the ligand L to the Zn(Ⅱ) ion. CCDC: 1484068, 1; 1484069, 2; 1484070, 3; 1484071, 4; 1484072, 5.
Five complexes, [CuLCl2]·CH3COCH3 (1), [ZnLCl2]·CH3COCH3 (2), [ZnL(NO3)2]·0.5CH3COCH3 (3), [AgL2]ClO4 (4) and [AgL2]BF4 (5) (L=2-(5-chloroquinolin-8-yloxy)-1-(pyrrolidin-1-yl)ethanone), were synthesized and characterized by X-ray diffraction. Complexes 1 and 2 are isostructural, and in each of them the five-coordinated metal ion is in a distorted tetragonal pyramid with a NO2 donor set from one ligand L and two chloride anions. However, the Zn(Ⅱ) ion in complex 3 is coordinated with one tridentate ligand L, one monodentate and one bidentate nitrate anions, giving a distorted octahedral coordination geometry. The structures of 1~3 are quite similar as those of the acetonitrile solvates derived from the same ligand L and metal salts. By contrast, the ratio of the metal ion and ligand L is 1:2 in complexes 4 and 5, the central Ag(Ⅰ) ion in each complex is six-coordinated with two independent ligands with N2O donor set, thus possesses a distorted octahedral coordination geometry. In CH3CN solution, the emission spectra of complexes 1, 3, 4 and 5 exhibit similar peak at 410 nm as the ligand L. However, the emission band of complex 3 red-shifts to 430 nm because of energy transferring from the ligand L to the Zn(Ⅱ) ion. CCDC: 1484068, 1; 1484069, 2; 1484070, 3; 1484071, 4; 1484072, 5.
2016, 32(9): 1659-1666
doi: 10.11862/CJIC.2016.214
Abstract:
Two novel Cu complexes, [Cu(Ⅱ)(phen)2Br]2[Cu(Ⅰ)4Br6] (1) and [Cu(Ⅱ)(phen)2Br]Br·CH3OH (2) (phen=1,10-phenanthroline), have been synthesized in alcohol and characterized by infrared spectroscopy, elemental analysis, thermal analysis, and X-ray diffraction single-crystal structure analysis. The structure of 1 with a Cu(Ⅰ)-Cu(Ⅱ) mixed valence can be described as a supramolecular network assembled via the combination of π-π interactions and C-H…Br hydrogen bonds. Its unit cell structure contains two [Cu(Ⅱ)(phen)2Br]+ ions and one tetranuclear [Cu(Ⅰ)4Br6]2- ion; four Cu atoms in the [Cu(Ⅰ)4Br6]2- anion are at corners of a tetrahedron, and six bromine atoms bridging along its six sides constitute an octahedron. The complex 2 consists of [Cu(Ⅱ)(phen)2Br]+, Br- and CH3OH, and a supramolecular framework is formed by π-π interactions. When 1 and 2 were used as catalysts for the oxidative carbonylation of methanol to dimethyl carbonate (DMC), 2 exhibits a turnover number of only 5.9 for DMC, while the [Cu(Ⅰ)4Br6]2- anion in 1 provides a suitable environment for the oxidative carbonylation of methanol, and the turnover number for DMC are up to 54.7. CCDC: 1437662, 1; 1014482, 2.
Two novel Cu complexes, [Cu(Ⅱ)(phen)2Br]2[Cu(Ⅰ)4Br6] (1) and [Cu(Ⅱ)(phen)2Br]Br·CH3OH (2) (phen=1,10-phenanthroline), have been synthesized in alcohol and characterized by infrared spectroscopy, elemental analysis, thermal analysis, and X-ray diffraction single-crystal structure analysis. The structure of 1 with a Cu(Ⅰ)-Cu(Ⅱ) mixed valence can be described as a supramolecular network assembled via the combination of π-π interactions and C-H…Br hydrogen bonds. Its unit cell structure contains two [Cu(Ⅱ)(phen)2Br]+ ions and one tetranuclear [Cu(Ⅰ)4Br6]2- ion; four Cu atoms in the [Cu(Ⅰ)4Br6]2- anion are at corners of a tetrahedron, and six bromine atoms bridging along its six sides constitute an octahedron. The complex 2 consists of [Cu(Ⅱ)(phen)2Br]+, Br- and CH3OH, and a supramolecular framework is formed by π-π interactions. When 1 and 2 were used as catalysts for the oxidative carbonylation of methanol to dimethyl carbonate (DMC), 2 exhibits a turnover number of only 5.9 for DMC, while the [Cu(Ⅰ)4Br6]2- anion in 1 provides a suitable environment for the oxidative carbonylation of methanol, and the turnover number for DMC are up to 54.7. CCDC: 1437662, 1; 1014482, 2.
2016, 32(9): 1667-1675
doi: 10.11862/CJIC.2016.191
Abstract:
The hydrothermal reactions of 3,5-dinitrobenzoic acid (3,5-DNBH), 1,2-bis(imidazol-1-ylmethyl)benzene (1,2-bimb) and transition metal salts result in three new transition metal coordination complexes, namely, [M(3,5-DNB)2(1,2-bimb)] (M=Co(Ⅱ) (1), Cd(Ⅱ) (3)) and [Zn(3,5-DNB)2(1,2-bimb)]n (2). These complexes were characterized by IR spectra, elemental analyses, single-crystal and powder X-ray diffraction analyses. Complexes 1 and 3 are isostructural and contain a dinuclear [M2(COO)2] (M=Co(Ⅱ) (1), Cd(Ⅱ) (3)) unit made up of metal ions, 3,5-DNB-and 1,2-bimb ligands, which further form the supramolecular structures by the O…π interactions between the nitro group oxygen atom of 3,5-DNB- anions and the benzene ring of 1,2-bimb molecules. Complex 2 features a 1D chain structure, which further packs to the supramolecular structure by the π…π interactions between the benzene rings from the 3,5-DNB- anions. The fluorescence properties of the dispersion methanol solution of complexes 2 and 3 have been investigated at room temperature. Relatively high thermal stabilities are found in the three complexes according to the TGA curves. Photocatalytic studies of 1 indicate good degradation ability over rhodamine B (RhB) under visible light irradiation. Furthermore, the dc magnetic susceptibility measurement of 1 reveals that dominant antiferromagnetic interactions are propagated between the Co(Ⅱ) ions in 1. CCDC: 1476334, 1; 1476335, 2; 1476336, 3.
The hydrothermal reactions of 3,5-dinitrobenzoic acid (3,5-DNBH), 1,2-bis(imidazol-1-ylmethyl)benzene (1,2-bimb) and transition metal salts result in three new transition metal coordination complexes, namely, [M(3,5-DNB)2(1,2-bimb)] (M=Co(Ⅱ) (1), Cd(Ⅱ) (3)) and [Zn(3,5-DNB)2(1,2-bimb)]n (2). These complexes were characterized by IR spectra, elemental analyses, single-crystal and powder X-ray diffraction analyses. Complexes 1 and 3 are isostructural and contain a dinuclear [M2(COO)2] (M=Co(Ⅱ) (1), Cd(Ⅱ) (3)) unit made up of metal ions, 3,5-DNB-and 1,2-bimb ligands, which further form the supramolecular structures by the O…π interactions between the nitro group oxygen atom of 3,5-DNB- anions and the benzene ring of 1,2-bimb molecules. Complex 2 features a 1D chain structure, which further packs to the supramolecular structure by the π…π interactions between the benzene rings from the 3,5-DNB- anions. The fluorescence properties of the dispersion methanol solution of complexes 2 and 3 have been investigated at room temperature. Relatively high thermal stabilities are found in the three complexes according to the TGA curves. Photocatalytic studies of 1 indicate good degradation ability over rhodamine B (RhB) under visible light irradiation. Furthermore, the dc magnetic susceptibility measurement of 1 reveals that dominant antiferromagnetic interactions are propagated between the Co(Ⅱ) ions in 1. CCDC: 1476334, 1; 1476335, 2; 1476336, 3.
2016, 32(9): 1676-1682
doi: 10.11862/CJIC.2016.211
Abstract:
By linking two 4, 4′-pyridine groups through an azo linker, ligand trans-and cis-1, 2-di((4, 4′-bipyridine)-3-yl)diazene (trans-and cis-L) were obtained. And the syntheses of two silver and cobalt complexes {[Ag2(trans-L)(ClO4)2]·4CH3CN}n(1) and {[Co(trans-L)2(H2O)2](ClO4)2}n(2) with the trans-form ligand are reported respectively. The complexes exhibited diverse structure features. And the application of Co complex as a photocatalyst was showed on the light driven hydrogen evolution. CCDC: 1497801, trans-L acetate; 1497799, cis-L; 1497798, 1; 1497800, 2.
By linking two 4, 4′-pyridine groups through an azo linker, ligand trans-and cis-1, 2-di((4, 4′-bipyridine)-3-yl)diazene (trans-and cis-L) were obtained. And the syntheses of two silver and cobalt complexes {[Ag2(trans-L)(ClO4)2]·4CH3CN}n(1) and {[Co(trans-L)2(H2O)2](ClO4)2}n(2) with the trans-form ligand are reported respectively. The complexes exhibited diverse structure features. And the application of Co complex as a photocatalyst was showed on the light driven hydrogen evolution. CCDC: 1497801, trans-L acetate; 1497799, cis-L; 1497798, 1; 1497800, 2.
2016, 32(9): 1683-1691
doi: 10.11862/CJIC.2016.216
Abstract:
Two novel coordination polymers, {[Zn(L)(4,4′-bpy)0.5]·2H2O}n(1) and {[Zn(L)(bpe)0.5]·2H2O}n (2) (H2L=5-(4-hydroxypyridinium-1-ylmethyl)isophthalic acid, 4,4′-bpy=4,4′-bipyridine, bpe=1,2-bis(4-pyridyl)ethylene), have been hydrothermally synthesized. Both compound 1 and 2 were structurally characterized by X-ray diffraction analyses, infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Compound 1 exhibits a three-dimensional (3D) 3-fold interpenetrating framework. Compound 2 has the similar 2D double-layer structure and exhibits a 3-fold parallel interpenetrated 2D→3D network motif. Meanwhile, their luminescent properties have also been investigated in detail. CCDC: 908520, 1; 908521, 2.
Two novel coordination polymers, {[Zn(L)(4,4′-bpy)0.5]·2H2O}n(1) and {[Zn(L)(bpe)0.5]·2H2O}n (2) (H2L=5-(4-hydroxypyridinium-1-ylmethyl)isophthalic acid, 4,4′-bpy=4,4′-bipyridine, bpe=1,2-bis(4-pyridyl)ethylene), have been hydrothermally synthesized. Both compound 1 and 2 were structurally characterized by X-ray diffraction analyses, infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Compound 1 exhibits a three-dimensional (3D) 3-fold interpenetrating framework. Compound 2 has the similar 2D double-layer structure and exhibits a 3-fold parallel interpenetrated 2D→3D network motif. Meanwhile, their luminescent properties have also been investigated in detail. CCDC: 908520, 1; 908521, 2.
2016, 32(9): 1503-1511
doi: 10.11862/CJIC.2016.215
Abstract:
The SiO2 encapsulated Fe3O4 composite magnetic microsphere was synthesized by a modified Stöber method with Fe3O4 nanoparticles as cores. The structures and properties of the composite were characterized by XRD, SEM, TEM, N2 absorption-desorption, FTIR and VSM. The results showed that the as-prepared magnetic microspheres exhibited a spherical shape and uniform particle size distribution. This material possessed a BET surface area of 413 m2·g-1 and saturation magnetization of 68.93 emu·g-1, respectively. The particle morphology became more uniform with the increase of TEOS volumes when silica shell became thicker. The saturation magnetization of the nanocomposite particles decrease with the thickness of the silica shell increasing, the coercive force of particles was almost unchanged, and remained favorable to superparamagnetism. Based on the composite magnetic microsphere, the new magnetic nano-adsorbent Fe3O4@SiO2@mSiO2-NH2 was fabricated by coating silica from a covalent binding of amino(-NH2) onto the surface of Fe3O4@SiO2@mSiO2 microsphere. And the adsorption properties of the adsorbent for Cr(Ⅵ) ions were investigated. The study on kinetics of Cr(Ⅵ) showed that the adsorption reaction could be considered as the pseudo-second-order kinetic model. The adsorption capability was significantly affected by the distributions of Cr(Ⅵ) species and -NH2. The adsorption mechanisms of Cr(Ⅵ) including both ion exchange and electrostatic gravitation were also discussed.
The SiO2 encapsulated Fe3O4 composite magnetic microsphere was synthesized by a modified Stöber method with Fe3O4 nanoparticles as cores. The structures and properties of the composite were characterized by XRD, SEM, TEM, N2 absorption-desorption, FTIR and VSM. The results showed that the as-prepared magnetic microspheres exhibited a spherical shape and uniform particle size distribution. This material possessed a BET surface area of 413 m2·g-1 and saturation magnetization of 68.93 emu·g-1, respectively. The particle morphology became more uniform with the increase of TEOS volumes when silica shell became thicker. The saturation magnetization of the nanocomposite particles decrease with the thickness of the silica shell increasing, the coercive force of particles was almost unchanged, and remained favorable to superparamagnetism. Based on the composite magnetic microsphere, the new magnetic nano-adsorbent Fe3O4@SiO2@mSiO2-NH2 was fabricated by coating silica from a covalent binding of amino(-NH2) onto the surface of Fe3O4@SiO2@mSiO2 microsphere. And the adsorption properties of the adsorbent for Cr(Ⅵ) ions were investigated. The study on kinetics of Cr(Ⅵ) showed that the adsorption reaction could be considered as the pseudo-second-order kinetic model. The adsorption capability was significantly affected by the distributions of Cr(Ⅵ) species and -NH2. The adsorption mechanisms of Cr(Ⅵ) including both ion exchange and electrostatic gravitation were also discussed.
2016, 32(9): 1512-1518
doi: 10.11862/CJIC.2016.193
Abstract:
A series of GdVO4:Dy3+, GdVO4:Dy3+, Eu3+ and GdVO4:Dy3+, Eu3+, Tm3+ phosphors were synthesized by the facile hydrothermal method using EDTA as mineralizer. The phase structure, morphology, photoluminescence properties, the energy transfer from Dy3+ to Eu3+ ions and the 4F9/2→615/2H transition of the Dy3+ ion in GdVO4:0.03Dy3+, xEu3+ phosphors have been investigated in detail. The X-ray diffraction (XRD) patterns reveal that GdVO4:0.03Dy3+, GdVO4:0.03Dy3+, 0.07Eu3+ and GdVO4:0.03Dy3+, 0.07Eu3+, 0.07Tm3+ phosphors have pure tetragonal crystal structure. The GdVO4:0.03Dy3+, 0.07Eu3+ and GdVO4:0.03Dy3+, 0.07Eu3+, 0.07Tm3+ phosphors are nanorod morphology with a mean length of about 0.458 and 0.491 μm as shown in the SEM images. By studying the decay times of GdVO4:Dy3+, Eu3+ phosphors, the energy transfer process from Dy3+ to Eu3+ was proved. And the mechanism of energy transfer is proved to be the dipole-dipole (d-d) interaction. By adjusting the concentration of Eu3+ in the GdVO4:0.03Dy3+, xEu3+ phosphors, the quasi white light (0.424, 0.350) is obtained. By adjusting the concentration of Tm3+ in the GdVO4:0.03Dy3+, 0.07Eu3+, yTm3+ phosphors, the white light (0.346, 0.301) is obtained.
A series of GdVO4:Dy3+, GdVO4:Dy3+, Eu3+ and GdVO4:Dy3+, Eu3+, Tm3+ phosphors were synthesized by the facile hydrothermal method using EDTA as mineralizer. The phase structure, morphology, photoluminescence properties, the energy transfer from Dy3+ to Eu3+ ions and the 4F9/2→615/2H transition of the Dy3+ ion in GdVO4:0.03Dy3+, xEu3+ phosphors have been investigated in detail. The X-ray diffraction (XRD) patterns reveal that GdVO4:0.03Dy3+, GdVO4:0.03Dy3+, 0.07Eu3+ and GdVO4:0.03Dy3+, 0.07Eu3+, 0.07Tm3+ phosphors have pure tetragonal crystal structure. The GdVO4:0.03Dy3+, 0.07Eu3+ and GdVO4:0.03Dy3+, 0.07Eu3+, 0.07Tm3+ phosphors are nanorod morphology with a mean length of about 0.458 and 0.491 μm as shown in the SEM images. By studying the decay times of GdVO4:Dy3+, Eu3+ phosphors, the energy transfer process from Dy3+ to Eu3+ was proved. And the mechanism of energy transfer is proved to be the dipole-dipole (d-d) interaction. By adjusting the concentration of Eu3+ in the GdVO4:0.03Dy3+, xEu3+ phosphors, the quasi white light (0.424, 0.350) is obtained. By adjusting the concentration of Tm3+ in the GdVO4:0.03Dy3+, 0.07Eu3+, yTm3+ phosphors, the white light (0.346, 0.301) is obtained.
2016, 32(9): 1519-1525
doi: 10.11862/CJIC.2016.212
Abstract:
Er3+-Yb3+ co-doped Gd2Ti2O7 powders were prepared by Sol-gel method. The optimal experiment design theory was used to build the regression equation between the luminescent intensity and the Er3+-Yb3+ doping concentration. Calculated by genetic algorithm, the optimal concentrations of Er3+ and Yb3+ solution were 5.60% (mole percentage) and 13.43%, respectively. Er3+-Yb3+ codoped Gd2Ti2O7 powders were characteristic of a typical face-centered cubic crystal phase, and the X-ray diffraction peaks shift toward higher angles with increasing Yb3+ concentration. Under 976 nm laser diode excitation, both green and red upconversion emissions were observed, corresponding to the Er3+ transitions of 2H11/2/4S3/2→4I15/2 and 4F9/2→4I15/2. The two-photon absorption upconversion process was responsible for the green and red emissions. The effect of temperature on green and red upconversion emissions from the optimal sample was studied, indicating that the green upconversion emissions have the optimized temperature sensing properties. The temperature-dependent red upconversion emissions were interpreted by the thermal quenching theory.
Er3+-Yb3+ co-doped Gd2Ti2O7 powders were prepared by Sol-gel method. The optimal experiment design theory was used to build the regression equation between the luminescent intensity and the Er3+-Yb3+ doping concentration. Calculated by genetic algorithm, the optimal concentrations of Er3+ and Yb3+ solution were 5.60% (mole percentage) and 13.43%, respectively. Er3+-Yb3+ codoped Gd2Ti2O7 powders were characteristic of a typical face-centered cubic crystal phase, and the X-ray diffraction peaks shift toward higher angles with increasing Yb3+ concentration. Under 976 nm laser diode excitation, both green and red upconversion emissions were observed, corresponding to the Er3+ transitions of 2H11/2/4S3/2→4I15/2 and 4F9/2→4I15/2. The two-photon absorption upconversion process was responsible for the green and red emissions. The effect of temperature on green and red upconversion emissions from the optimal sample was studied, indicating that the green upconversion emissions have the optimized temperature sensing properties. The temperature-dependent red upconversion emissions were interpreted by the thermal quenching theory.
2016, 32(9): 1526-1534
doi: 10.11862/CJIC.2016.208
Abstract:
Zinc ferrite/expanded graphite (ZF/EG) composites were prepared using a simple chemical co-precipitation method. The composition, microstructure, magnetic property, adsorption and photocatalytic activity of the samples were characterized by means of modern analytical techniques. And the results showed that the magnetic composite not only held the original special structure and good adsorption properties of EG, but also had suitable magnetic property and photocatalytic activity. The removal rate of the samples on humic acid depends on the mass ratio of ZF to EG (mZF/mE), adsorption time and pH of the solution, and so on. Removal rate of 0.1 g ZF/EG composite with mEG/mZF=1 on humic acid (15 mg·L-1, 100 mL, pH=7) was up to 95% under UV irradiation. After repeated use 4 times, removal rate of the composite on the humic acid declined only 4%. In addition, the samples can be recovered conveniently, activated easily and had good performance for recycling, and were thought to be a promising green and high-efficiency material in dealing with wastewater.
Zinc ferrite/expanded graphite (ZF/EG) composites were prepared using a simple chemical co-precipitation method. The composition, microstructure, magnetic property, adsorption and photocatalytic activity of the samples were characterized by means of modern analytical techniques. And the results showed that the magnetic composite not only held the original special structure and good adsorption properties of EG, but also had suitable magnetic property and photocatalytic activity. The removal rate of the samples on humic acid depends on the mass ratio of ZF to EG (mZF/mE), adsorption time and pH of the solution, and so on. Removal rate of 0.1 g ZF/EG composite with mEG/mZF=1 on humic acid (15 mg·L-1, 100 mL, pH=7) was up to 95% under UV irradiation. After repeated use 4 times, removal rate of the composite on the humic acid declined only 4%. In addition, the samples can be recovered conveniently, activated easily and had good performance for recycling, and were thought to be a promising green and high-efficiency material in dealing with wastewater.
2016, 32(9): 1535-1542
doi: 10.11862/CJIC.2016.201
Abstract:
Cerium dioxide (CeO2) hollow microspheres have been prepared via bio-template and precipitation method using yeast as template. The products were characterized by Fourier transform infrared, X-ray diffraction, X-ray photoelectron spectra, scanning electron microscopy, transmission electron microscopy and N2 adsorption-desorption isotherms. The results showed that the CeO2 hollow microspheres were obtained after calcination at 600 ℃, and their shapes were approximately ellipsoid same as the yeasts. The shell of the as-prepared hollow microspheres is composed of CeO2 nanoparticles with size of ~25 nm. The specific surface area of the sample is 22 m2·g-1 which is higher than the sample prepared without templates. The band gap energy of the CeO2 hollow microsphere (3.03 eV) is small compared with the samples prepared without templates (3.42 eV) via UV-Vis diffuse reflectance spectrum. The as-prepared CeO2 hollow microspheres exhibit good photocatalytic activity for the degradation of acid orange 7 (AO 7) at room temperature under solar light irradiation. The degradation rate of AO 7 can be 96% after 120 min which is much higher than that of samples prepared without templates. The formation mechanism of CeO2 hollow microspheres has been proposed.
Cerium dioxide (CeO2) hollow microspheres have been prepared via bio-template and precipitation method using yeast as template. The products were characterized by Fourier transform infrared, X-ray diffraction, X-ray photoelectron spectra, scanning electron microscopy, transmission electron microscopy and N2 adsorption-desorption isotherms. The results showed that the CeO2 hollow microspheres were obtained after calcination at 600 ℃, and their shapes were approximately ellipsoid same as the yeasts. The shell of the as-prepared hollow microspheres is composed of CeO2 nanoparticles with size of ~25 nm. The specific surface area of the sample is 22 m2·g-1 which is higher than the sample prepared without templates. The band gap energy of the CeO2 hollow microsphere (3.03 eV) is small compared with the samples prepared without templates (3.42 eV) via UV-Vis diffuse reflectance spectrum. The as-prepared CeO2 hollow microspheres exhibit good photocatalytic activity for the degradation of acid orange 7 (AO 7) at room temperature under solar light irradiation. The degradation rate of AO 7 can be 96% after 120 min which is much higher than that of samples prepared without templates. The formation mechanism of CeO2 hollow microspheres has been proposed.
2016, 32(9): 1543-1551
doi: 10.11862/CJIC.2016.205
Abstract:
Ag@AgBr/Ni thin films plasmonic photocatalyst were prepared by electrochemical method. The surface morphology, phase structure, optical characteristics of the thin films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS), respectively. Its photoelectrocatalytic properties and stability at negative bias under visible light were evaluated with rhodamine B (RhB) as a model compound. Using eletrochemical technique and a method of adding active species scavenger to the solution, mechanism of photoelectrocatalytic degradation of the films were explored. The results show that the Ag@AgBr/Ni thin film prepared under optimum condition are composed of AgBr microparticles whose surface has silver nanoparticles with a significant surface plasmon resonance (SPR) effects. The Ag@AgBr/Ni film is photoelectrocatalytically more active than TiO2/ITO (indium tin oxide) film. At optimum cathodic bias and under visible light irradiation in 12 min, the photoelectrocatalytic degradation rate of Ag@AgBr/Ni film is 10.2 times as much as that of porous TiO2(Degussa P25)/ITO film. Compared with no cathodic bias, the photoeletrocatalytic degradation rate of the Ag@AgBr/Ni thin film to RhB is increased by 2.0 times and the thin film has obvious photoelectric synergistic effect. The photoelectrocatalytic activity almost kept unchanged after five recycled experiments. The improvement in photoelectrocatalytic activity for Ag@AgBr/Ni thin films could be mainly attributed to the activation of nano Ag particles on the electrode for photocathode reaction (Conduction band reaction) with a significant SPR effects. Furthermore, the photoelctrocatalytic reaction mechanism of Ag@AgBr/Ni thin films for RhB at negative bias was proposed.
Ag@AgBr/Ni thin films plasmonic photocatalyst were prepared by electrochemical method. The surface morphology, phase structure, optical characteristics of the thin films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS), respectively. Its photoelectrocatalytic properties and stability at negative bias under visible light were evaluated with rhodamine B (RhB) as a model compound. Using eletrochemical technique and a method of adding active species scavenger to the solution, mechanism of photoelectrocatalytic degradation of the films were explored. The results show that the Ag@AgBr/Ni thin film prepared under optimum condition are composed of AgBr microparticles whose surface has silver nanoparticles with a significant surface plasmon resonance (SPR) effects. The Ag@AgBr/Ni film is photoelectrocatalytically more active than TiO2/ITO (indium tin oxide) film. At optimum cathodic bias and under visible light irradiation in 12 min, the photoelectrocatalytic degradation rate of Ag@AgBr/Ni film is 10.2 times as much as that of porous TiO2(Degussa P25)/ITO film. Compared with no cathodic bias, the photoeletrocatalytic degradation rate of the Ag@AgBr/Ni thin film to RhB is increased by 2.0 times and the thin film has obvious photoelectric synergistic effect. The photoelectrocatalytic activity almost kept unchanged after five recycled experiments. The improvement in photoelectrocatalytic activity for Ag@AgBr/Ni thin films could be mainly attributed to the activation of nano Ag particles on the electrode for photocathode reaction (Conduction band reaction) with a significant SPR effects. Furthermore, the photoelctrocatalytic reaction mechanism of Ag@AgBr/Ni thin films for RhB at negative bias was proposed.
2016, 32(9): 1552-1558
doi: 10.11862/CJIC.2016.196
Abstract:
A modified Graphite felt cathode have been obtained by pretreatment of H2O2 and modification of transition metal oxide (CeO2). The results indicated that H2O2 pretreatment increased the oxygen-containing groups on the surface of graphite felt and improved the surface hydrophilicity, which helped to the deposition of CeO2, and X-ray diffraction (XRD) showed that the CeO2 deposited on the surface of graphite felt was a typical fluorite structure. The EIS and CV analysis indicated a decrease of the charge transfer and an increase of the oxygen reduction current of the modified cathode, while the active surface area was improved by 8 times. The LSV result showed that the electric current density of cathode after modification was significantly enhanced, which was 8.5 times the amount of the pristine one. The modified graphite felt was used as cathode by electro-Fenton to remediate the solution of methyl orange, the decolorization rate reached to 96.8% in 20 min and the removal rate increased 133.2% compared to the unmodified graphite felt, and the electrochemical oxidation performance of the modified graphite felt was obviously improved.
A modified Graphite felt cathode have been obtained by pretreatment of H2O2 and modification of transition metal oxide (CeO2). The results indicated that H2O2 pretreatment increased the oxygen-containing groups on the surface of graphite felt and improved the surface hydrophilicity, which helped to the deposition of CeO2, and X-ray diffraction (XRD) showed that the CeO2 deposited on the surface of graphite felt was a typical fluorite structure. The EIS and CV analysis indicated a decrease of the charge transfer and an increase of the oxygen reduction current of the modified cathode, while the active surface area was improved by 8 times. The LSV result showed that the electric current density of cathode after modification was significantly enhanced, which was 8.5 times the amount of the pristine one. The modified graphite felt was used as cathode by electro-Fenton to remediate the solution of methyl orange, the decolorization rate reached to 96.8% in 20 min and the removal rate increased 133.2% compared to the unmodified graphite felt, and the electrochemical oxidation performance of the modified graphite felt was obviously improved.
2016, 32(9): 1559-1564
doi: 10.11862/CJIC.2016.197
Abstract:
Under hydrothermal conditions, three novel complexes {[Co(en)3]·[KLa2(C2O4)5(H2O)6]·H2O}n (HNU-9), {[Co(dien)2][La2(C2O4)4(H2O)2]·xH2O}n (HNU-11) and {K3[Co(dien)2][La4(C2O4)9(H2O)2]·5H2O}n (HNU-12) were synthesized by using Co(Ⅲ) complexes as template. Different templates ([Co(en)3]3+, [Co(dien)2]3+, K++[Co(dien)2]3+) exist in compounds in different ways, leading to different three-dimensional framework structures. Interesting, the structures of HNU-11 and HNU-12 present the novel topology structure due to different coordination modes of the central La3+. Therefore, it is suggested that rare earth metal with higher coordination number more easily lead to form complexes with novel structure. CCDC: 1495537, HNU-9; 1495538, HUN-11; 1495539, HUN-12.
Under hydrothermal conditions, three novel complexes {[Co(en)3]·[KLa2(C2O4)5(H2O)6]·H2O}n (HNU-9), {[Co(dien)2][La2(C2O4)4(H2O)2]·xH2O}n (HNU-11) and {K3[Co(dien)2][La4(C2O4)9(H2O)2]·5H2O}n (HNU-12) were synthesized by using Co(Ⅲ) complexes as template. Different templates ([Co(en)3]3+, [Co(dien)2]3+, K++[Co(dien)2]3+) exist in compounds in different ways, leading to different three-dimensional framework structures. Interesting, the structures of HNU-11 and HNU-12 present the novel topology structure due to different coordination modes of the central La3+. Therefore, it is suggested that rare earth metal with higher coordination number more easily lead to form complexes with novel structure. CCDC: 1495537, HNU-9; 1495538, HUN-11; 1495539, HUN-12.
2016, 32(9): 1565-1571
doi: 10.11862/CJIC.2016.209
Abstract:
The plumbic and stannic perovskite solar cell materials such as CH3NH3SnI3 and CH3NH3PbI3 were obtained by one step preparation with the surface morphology, microstructure, spectral absorption and device performance were investigated respectively. The spectral absorption of stannic perovskite material were found to expand wider and have an obvious red-shift compared to plumbic perovskite, with the absorption edge increased from 800 to 950 nm and the optical band gap reduced from 1.45 to 1.21 eV. But the conversion efficiency of stannic perovskite solar cell demonstrated significantly lower than that of plumbic perovskite, 2.05% and 6.71% respectively, due to a downshift of absorption intensity. However, bromine (Br) doping could broaden the band gap and thus give rise to the open circuit voltage of solar cell device accordingly. As the doping content increased from 0 to be totally replacement of iodine, the color of stannic perovskite turned gradually from dark brown to yellow, and the optical band gap increased up to 1.95 eV. At the same time, a blue shift of spectra absorption was observed, reducing from 950 to 650 nm. Noteworthy is that the solar cell conversion efficiency increased from initial 2.05% to 2.94% at the doping content of 0.5.
The plumbic and stannic perovskite solar cell materials such as CH3NH3SnI3 and CH3NH3PbI3 were obtained by one step preparation with the surface morphology, microstructure, spectral absorption and device performance were investigated respectively. The spectral absorption of stannic perovskite material were found to expand wider and have an obvious red-shift compared to plumbic perovskite, with the absorption edge increased from 800 to 950 nm and the optical band gap reduced from 1.45 to 1.21 eV. But the conversion efficiency of stannic perovskite solar cell demonstrated significantly lower than that of plumbic perovskite, 2.05% and 6.71% respectively, due to a downshift of absorption intensity. However, bromine (Br) doping could broaden the band gap and thus give rise to the open circuit voltage of solar cell device accordingly. As the doping content increased from 0 to be totally replacement of iodine, the color of stannic perovskite turned gradually from dark brown to yellow, and the optical band gap increased up to 1.95 eV. At the same time, a blue shift of spectra absorption was observed, reducing from 950 to 650 nm. Noteworthy is that the solar cell conversion efficiency increased from initial 2.05% to 2.94% at the doping content of 0.5.
2016, 32(9): 1572-1578
doi: 10.11862/CJIC.2016.198
Abstract:
Two new complexes [Cu(Him)L]2 (1) and [Ni(Him)L] (2), where H2L is 2-thiophenecarboxylic acid (2-hydroxly-5-nitro-benzylidene)-hydrazide and Him is imidazole, were synthesized by hydrothermal reaction and characterized by elemental analysis, FT-IR and electronic spectra. The structure of complexes has been accomplished by single crystal X-ray diffraction which results confirmed that the crystal of 1 belongs to the monoclinic system, space group P21/c with cell parameters: a=1.135 68(12) nm, b=0.770 45(8) nm, c=2.140 4(2) nm, β=97.405(3)° and the crystal of 2 belongs to the triclinic system, space group P1 with cell parameters: a=0.726 91(4) nm, b=0.976 34(6) nm, c=1.265 74(8) nm, α=79.533(2)°, β=82.862(2)°, γ=68.985(2)°. The X-ray analyses revealed that 1 displays a centrosymmetric binuclear structure with the Cu atoms in square pyramidal coordination. The binuclear units are further linked by hydrogen bonds to generate an infinite 1D chain. The mononuclear units in 2 are linked through weak N-H…O and C-H…O hydrogen bonds to form an infinite 2D network. The in vitro antitumor activities of ligand and complexes were tested by MTT method, which results show that 1 and 2 have strong in vitro antitumor activity against HEPG2 and SW620 cancer cells lines. CCDC: 1041671, 1; CCDC 1041672, 2.
Two new complexes [Cu(Him)L]2 (1) and [Ni(Him)L] (2), where H2L is 2-thiophenecarboxylic acid (2-hydroxly-5-nitro-benzylidene)-hydrazide and Him is imidazole, were synthesized by hydrothermal reaction and characterized by elemental analysis, FT-IR and electronic spectra. The structure of complexes has been accomplished by single crystal X-ray diffraction which results confirmed that the crystal of 1 belongs to the monoclinic system, space group P21/c with cell parameters: a=1.135 68(12) nm, b=0.770 45(8) nm, c=2.140 4(2) nm, β=97.405(3)° and the crystal of 2 belongs to the triclinic system, space group P1 with cell parameters: a=0.726 91(4) nm, b=0.976 34(6) nm, c=1.265 74(8) nm, α=79.533(2)°, β=82.862(2)°, γ=68.985(2)°. The X-ray analyses revealed that 1 displays a centrosymmetric binuclear structure with the Cu atoms in square pyramidal coordination. The binuclear units are further linked by hydrogen bonds to generate an infinite 1D chain. The mononuclear units in 2 are linked through weak N-H…O and C-H…O hydrogen bonds to form an infinite 2D network. The in vitro antitumor activities of ligand and complexes were tested by MTT method, which results show that 1 and 2 have strong in vitro antitumor activity against HEPG2 and SW620 cancer cells lines. CCDC: 1041671, 1; CCDC 1041672, 2.
2016, 32(9): 1579-1584
doi: 10.11862/CJIC.2016.202
Abstract:
Two complexes {[Hg(L1)Cl2]·CH3OH}n (1) and [Hg(L2)Cl2]n (2) were synthesized from the reaction of Schiff base ligand 3-acetylpyridine-o-aminobenzoylhydrazone (L1) and ligand 4-acetylpyridine-o-aminobenzoylhy-drazone (L2) with HgCl2, respectively. The compounds are characterized by 1H NMR, FTIR, and elemental analysis, and their structures are measured via single crystal X-ray diffraction. The results show that the complex 1 crystallize in triclinic system, space group P1; the complex 2 crystallize in monoclinic system, space group P21/n. Further the thermal stabilities of the two complexes were investigated. CCDC: 1496029, 1; 1496028, 2.
Two complexes {[Hg(L1)Cl2]·CH3OH}n (1) and [Hg(L2)Cl2]n (2) were synthesized from the reaction of Schiff base ligand 3-acetylpyridine-o-aminobenzoylhydrazone (L1) and ligand 4-acetylpyridine-o-aminobenzoylhy-drazone (L2) with HgCl2, respectively. The compounds are characterized by 1H NMR, FTIR, and elemental analysis, and their structures are measured via single crystal X-ray diffraction. The results show that the complex 1 crystallize in triclinic system, space group P1; the complex 2 crystallize in monoclinic system, space group P21/n. Further the thermal stabilities of the two complexes were investigated. CCDC: 1496029, 1; 1496028, 2.
