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2016 Volume 32 Issue 1
2016, 32(1): 1-8
doi: 10.11862/CJIC.2016.017
Abstract:
Two novel coordination polymers, [Cd(2-mba)(bimb)]n(1) and [Pb(2-sb)]n(2) [H2(2-mba)=2-mercaptobenzoic acid, bimb=4,4-bis(1-imidazolyl)bibenzene, sb2-=2-sulfinobenzoate] have been solvothermal synthesized and characterized by elemental analysis, IR, powder X-ray diffraction and single crystal X-ray diffraction. Complex 1 features a two-dimensional (2D) net structure in which 1D [Cd(2-mba)]n chains are interconnected by bimb ligands. In complex 1, the ligand 2-mercaptobenzoic acid was oxidized into 2-sulfinobenzoate under solvothermal conditions via in situ ligand reactions. Complex 2 exhibits a 2D(4, 4)-connected framework bridged with carboxylate and sulfinate groups of 2-sulfinobenzoate ligands. The thermal stabilities and solid state photoluminescent properties of two compounds were also investigated. CCDC: 1056796, 1; 1056797, 2.
Two novel coordination polymers, [Cd(2-mba)(bimb)]n(1) and [Pb(2-sb)]n(2) [H2(2-mba)=2-mercaptobenzoic acid, bimb=4,4-bis(1-imidazolyl)bibenzene, sb2-=2-sulfinobenzoate] have been solvothermal synthesized and characterized by elemental analysis, IR, powder X-ray diffraction and single crystal X-ray diffraction. Complex 1 features a two-dimensional (2D) net structure in which 1D [Cd(2-mba)]n chains are interconnected by bimb ligands. In complex 1, the ligand 2-mercaptobenzoic acid was oxidized into 2-sulfinobenzoate under solvothermal conditions via in situ ligand reactions. Complex 2 exhibits a 2D(4, 4)-connected framework bridged with carboxylate and sulfinate groups of 2-sulfinobenzoate ligands. The thermal stabilities and solid state photoluminescent properties of two compounds were also investigated. CCDC: 1056796, 1; 1056797, 2.
2016, 32(1): 25-33
doi: 10.11862/CJIC.2016.002
Abstract:
Molecular rotation and orientation by applied electric field is one of the promising strategies for assembling the potential molecular dielectric rotors and relax-like dielectric. Here, a new charge transfer compound [C10-DMPy][Ni(mnt)2] (1) (C10-DMPy+=1-decanel-N, N-dimethylpyridinium cation, mnt2-=maleonitriledithiolate), which shows interesting dielectric relaxation process, is synthesized and characterized. The anions and cations of 1 are aligned into segregated stacks. There existed weakly charge-assisted hydrogen bonding interactions between the mobile organic cation and rigid [Ni(mnt)2]- anion. Large temperature-dependent dielectric constant values and dielectric relaxation process of 1 can be ascribed to the dynamic orientation motion of alkyl chain of the organic cation and charge transfer between anions and cations. The overall magnetic behavior of 1 corresponds to a paramagnetic system with ferromagnetic coupling interaction. CCDC: 1415204, 1.
Molecular rotation and orientation by applied electric field is one of the promising strategies for assembling the potential molecular dielectric rotors and relax-like dielectric. Here, a new charge transfer compound [C10-DMPy][Ni(mnt)2] (1) (C10-DMPy+=1-decanel-N, N-dimethylpyridinium cation, mnt2-=maleonitriledithiolate), which shows interesting dielectric relaxation process, is synthesized and characterized. The anions and cations of 1 are aligned into segregated stacks. There existed weakly charge-assisted hydrogen bonding interactions between the mobile organic cation and rigid [Ni(mnt)2]- anion. Large temperature-dependent dielectric constant values and dielectric relaxation process of 1 can be ascribed to the dynamic orientation motion of alkyl chain of the organic cation and charge transfer between anions and cations. The overall magnetic behavior of 1 corresponds to a paramagnetic system with ferromagnetic coupling interaction. CCDC: 1415204, 1.
2016, 32(1): 49-55
doi: 10.11862/CJIC.2016.022
Abstract:
Er3+ doped and Er3+/Yb3+ co-doped La2TiO5 phosphors were synthesized by using sol-gel reactions. Good crystallinity was achieved after annealing the samples at 1 100 ℃ for 3 h in air. X-ray powder diffraction results revealed the formation of desired La2TiO5 host with pyrochlore structure. The UV excitation spectra of the samples consist of two regions in which the broad band at 250~320 nm originates from the charge-transition(CT) band between Er3+ ion and the nearest neighboring O2- ions and the sharp lines at 350~500 nm correspond to the f-f transition of Er3+ ion. Er3+ ion in La2TiO5 emits intense characteristic green light (546 nm, 4S3/2-4I15/2) under the excitation at 378 nm and the emission intensity reaches the maximum at Er3+ concentration of 1% (molar fraction). In the NIR-excited (980 nm) up-converted spectra, Yb3+ ion as an efficient sensitizer enhanced the emission intensities of Er3+ ion in comparison with those in La2TiO5:Er3+ phosphors. The luminescence decay curve and quantum yield were also measured and discussed in details.
Er3+ doped and Er3+/Yb3+ co-doped La2TiO5 phosphors were synthesized by using sol-gel reactions. Good crystallinity was achieved after annealing the samples at 1 100 ℃ for 3 h in air. X-ray powder diffraction results revealed the formation of desired La2TiO5 host with pyrochlore structure. The UV excitation spectra of the samples consist of two regions in which the broad band at 250~320 nm originates from the charge-transition(CT) band between Er3+ ion and the nearest neighboring O2- ions and the sharp lines at 350~500 nm correspond to the f-f transition of Er3+ ion. Er3+ ion in La2TiO5 emits intense characteristic green light (546 nm, 4S3/2-4I15/2) under the excitation at 378 nm and the emission intensity reaches the maximum at Er3+ concentration of 1% (molar fraction). In the NIR-excited (980 nm) up-converted spectra, Yb3+ ion as an efficient sensitizer enhanced the emission intensities of Er3+ ion in comparison with those in La2TiO5:Er3+ phosphors. The luminescence decay curve and quantum yield were also measured and discussed in details.
2016, 32(1): 124-130
doi: 10.11862/CJIC.2016.013
Abstract:
Clew-like α-MnO2 was synthesized by a solution phase synthesis method using MnSO4 and (NH4)2S2O8 as reactants and Ag+ ions as catalyst. The synthetic materials were characterized by XRD, SEM and TEM. It was found that the reaction temperature and reaction time have much influence on the crystallinity and morphology of the products. The electrochemical properties of the final products were tested by galvanostatic charge/discharge profile measurement and cyclic voltammetry (CV). The results show that the product prepared at 25 ℃ for 2 days as cathode material for lithium ion battery, exhibits excellent cycling stability (124 mAh·g-1 after 100 cycles) due to its unique morphology. The clew-structure α-MnO2 could be a potential cathode material for the application of lithium ion batteries (LIBs).
Clew-like α-MnO2 was synthesized by a solution phase synthesis method using MnSO4 and (NH4)2S2O8 as reactants and Ag+ ions as catalyst. The synthetic materials were characterized by XRD, SEM and TEM. It was found that the reaction temperature and reaction time have much influence on the crystallinity and morphology of the products. The electrochemical properties of the final products were tested by galvanostatic charge/discharge profile measurement and cyclic voltammetry (CV). The results show that the product prepared at 25 ℃ for 2 days as cathode material for lithium ion battery, exhibits excellent cycling stability (124 mAh·g-1 after 100 cycles) due to its unique morphology. The clew-structure α-MnO2 could be a potential cathode material for the application of lithium ion batteries (LIBs).
2016, 32(1): 131-138
doi: 10.11862/CJIC.2016.031
Abstract:
A cobalt (Ⅱ) complex, [CoLCl]2[CoLCl0.5(H2O)0.5]2ClO4·10H2O (1) (LH=(2-(bis ((1H-benzo[d]-imidazol-2-yl) methyl) amino) acetic acid)) has been synthesized and characterized. Its catecholase catalytic activity has been exploited by UV-Vis spectrophotometric study by using 3, 5-di-tert-butylcatechol (3, 5-DTBC) as the substrate. The results showed that two cobalt (Ⅱ) ions of the asymmetric unit were both coordinated by the ligands in a distorted trigonal-bipyramidal geometry in the crystal structure. Complex 1 exhibited pH value dependence for the oxidation of 3, 5-DTBC in the range of pH 5 to 11, and its catecholase catalytic activity increased with increasing temperature. The kinetics of oxidation of 3, 5-DTBC catalyzed by complex 1 accorded with the Michaelis-Mentent equation. CCDC: 950329, 1.
A cobalt (Ⅱ) complex, [CoLCl]2[CoLCl0.5(H2O)0.5]2ClO4·10H2O (1) (LH=(2-(bis ((1H-benzo[d]-imidazol-2-yl) methyl) amino) acetic acid)) has been synthesized and characterized. Its catecholase catalytic activity has been exploited by UV-Vis spectrophotometric study by using 3, 5-di-tert-butylcatechol (3, 5-DTBC) as the substrate. The results showed that two cobalt (Ⅱ) ions of the asymmetric unit were both coordinated by the ligands in a distorted trigonal-bipyramidal geometry in the crystal structure. Complex 1 exhibited pH value dependence for the oxidation of 3, 5-DTBC in the range of pH 5 to 11, and its catecholase catalytic activity increased with increasing temperature. The kinetics of oxidation of 3, 5-DTBC catalyzed by complex 1 accorded with the Michaelis-Mentent equation. CCDC: 950329, 1.
2016, 32(1): 139-144
doi: 10.11862/CJIC.2016.023
Abstract:
Two kinds of complexes [AgCl (PPh3)2(BTZT)]·CH3OH (1) and [AgCl (PPh3)2(BTZT)]2 (2) were obtained by the reaction of AgCl, PPh3, and MBT in 1:2:1 molar ratio (PPh3=triphenylphosphine; MBT=2-mercaptobenzo-thiazole BTZT=benzothiazoline-2-thione) (2 has been reported). [AgBr (PPh3)2(BTZT)]·CH3OH (3) and [AgBr (PPh3)2(BTZT)]2 (4) were prepared in a manner similar to 1 and 2 using AgBr (4 has been reported). Complexes 1 and 3 have been characterized by IR, elemental analysis, 1H NMR spectroscopy, fluorescence spectrum and single-crystal X-ray diffraction. The MBT ligand can transform into the BTZT ligand in different chemical environment because of its chemically active groups. The luminescent spectra show that emission peaks of 1 and 3 are assigned to the ligand centered π-π* transition. CCDC: 1407305, 1; 1407306, 3.
Two kinds of complexes [AgCl (PPh3)2(BTZT)]·CH3OH (1) and [AgCl (PPh3)2(BTZT)]2 (2) were obtained by the reaction of AgCl, PPh3, and MBT in 1:2:1 molar ratio (PPh3=triphenylphosphine; MBT=2-mercaptobenzo-thiazole BTZT=benzothiazoline-2-thione) (2 has been reported). [AgBr (PPh3)2(BTZT)]·CH3OH (3) and [AgBr (PPh3)2(BTZT)]2 (4) were prepared in a manner similar to 1 and 2 using AgBr (4 has been reported). Complexes 1 and 3 have been characterized by IR, elemental analysis, 1H NMR spectroscopy, fluorescence spectrum and single-crystal X-ray diffraction. The MBT ligand can transform into the BTZT ligand in different chemical environment because of its chemically active groups. The luminescent spectra show that emission peaks of 1 and 3 are assigned to the ligand centered π-π* transition. CCDC: 1407305, 1; 1407306, 3.
2016, 32(1): 145-152
doi: 10.11862/CJIC.2016.014
Abstract:
A M3 modification of tricalcium silicate (C3S) solid solution was investigated using transmission electron microscope (TEM). Selected area electron diffraction (SAED) patterns and high resolution transmission electron microscopy (HRTEM) images were analyzed based on a pseudohexagonal subcell (Space group R3m; a=0.705 9 nm, b=0.705 5 nm, c=2.492 4 nm, α=89.79°, β=90.04°, γ=120.14°). Reflections caused by the superstructure were proven to occur along the modulation wave vector [117]H* with one-dimensional type and could be expressed as ha*+kb*+lc*+m/[6(-a*+b*+7c*)], where m=±1, ±2 and±3. SAED patterns and HRTEM images based on the M3 supercell (Space group Cm; a=3.310 8 nm, b=0.703 6 nm, c=1.852 1 nm, β=94.137°) were simulated and finally the orientation relations between M3 supercell and pseudohexagonal subcell were established as follows: (600)M3, (020)M3 and (006)M3 were equivalent to (112)H, (110)H and (117)H respectively, and [100]M3//[772]H, [010]M3//[110]H, and [001]M3//[111]H. Furthermore, the conversion matrix between M3 supercell and pseudohexagonal subcell was established.
A M3 modification of tricalcium silicate (C3S) solid solution was investigated using transmission electron microscope (TEM). Selected area electron diffraction (SAED) patterns and high resolution transmission electron microscopy (HRTEM) images were analyzed based on a pseudohexagonal subcell (Space group R3m; a=0.705 9 nm, b=0.705 5 nm, c=2.492 4 nm, α=89.79°, β=90.04°, γ=120.14°). Reflections caused by the superstructure were proven to occur along the modulation wave vector [117]H* with one-dimensional type and could be expressed as ha*+kb*+lc*+m/[6(-a*+b*+7c*)], where m=±1, ±2 and±3. SAED patterns and HRTEM images based on the M3 supercell (Space group Cm; a=3.310 8 nm, b=0.703 6 nm, c=1.852 1 nm, β=94.137°) were simulated and finally the orientation relations between M3 supercell and pseudohexagonal subcell were established as follows: (600)M3, (020)M3 and (006)M3 were equivalent to (112)H, (110)H and (117)H respectively, and [100]M3//[772]H, [010]M3//[110]H, and [001]M3//[111]H. Furthermore, the conversion matrix between M3 supercell and pseudohexagonal subcell was established.
2016, 32(1): 153-160
doi: 10.11862/CJIC.2016.012
Abstract:
One heptanuclear Mn cluster [Mn3ⅡMn4Ⅲ(Cl)6(hmp)6(thme)2]·H2O·3CH3CN (1·H2O·3CH3CN, hmpH=2-(hydroxymethyl) pyridine and thmeH3=1, 1, 1-tris (hydroxymethyl) ethane) has been synthesized by the reaction of MnCl2·4H2O, hmpH and thmeH3 in MeCN. The complex was characterized by single crystal X-ray diffraction, elemental analyses, IR and magnetic investigation. Complex 1·H2O·3CH3CN crystallizes in the monoclinic space group I2/a and its core can be viewed as a Mn6 hexagon of alternating MnⅡ and MnⅢ ions surrounding a central MnⅢ ion, which has previously not been seen for this topology. Magnetic studies reveal that overall ferromagnetic coupling between MnⅢ and MnⅡ or MnⅢ ions within 1·H2O are present and weak frequency dependence of the ac-susceptibility was found. CCDC: 1045766.
One heptanuclear Mn cluster [Mn3ⅡMn4Ⅲ(Cl)6(hmp)6(thme)2]·H2O·3CH3CN (1·H2O·3CH3CN, hmpH=2-(hydroxymethyl) pyridine and thmeH3=1, 1, 1-tris (hydroxymethyl) ethane) has been synthesized by the reaction of MnCl2·4H2O, hmpH and thmeH3 in MeCN. The complex was characterized by single crystal X-ray diffraction, elemental analyses, IR and magnetic investigation. Complex 1·H2O·3CH3CN crystallizes in the monoclinic space group I2/a and its core can be viewed as a Mn6 hexagon of alternating MnⅡ and MnⅢ ions surrounding a central MnⅢ ion, which has previously not been seen for this topology. Magnetic studies reveal that overall ferromagnetic coupling between MnⅢ and MnⅡ or MnⅢ ions within 1·H2O are present and weak frequency dependence of the ac-susceptibility was found. CCDC: 1045766.
2016, 32(1): 161-166
doi: 10.11862/CJIC.2016.008
Abstract:
Two complexes, namely [Ni (L)2] (1) and [Cd (HL)(CH3OH)(NO3)2] (2) (HL is derived from 2-acetyl pyrazine and methyl hydrazinocarboxylate) have been synthesized and characterized by single-crystal X-ray diffraction, elemental analysis and IR spectroscopy. X-ray diffraction analysis results show that the central Ni (Ⅱ) ion in complex 1 is surrounded by two independent anionic ligands with N2O donor set, thus possesses a distorted octahedral coordination geometry. However, in complex 2, the Cd (Ⅱ) ion with bicapped-triangular prism geometry is coordinated with one neutral ligand HL, two bidentate nitrate anions and one methanol molecule. In addition, the thermal stability and luminescent properties of the complexes are also studied in detail. CCDC: 1424257, 1; 1424258, 2.
Two complexes, namely [Ni (L)2] (1) and [Cd (HL)(CH3OH)(NO3)2] (2) (HL is derived from 2-acetyl pyrazine and methyl hydrazinocarboxylate) have been synthesized and characterized by single-crystal X-ray diffraction, elemental analysis and IR spectroscopy. X-ray diffraction analysis results show that the central Ni (Ⅱ) ion in complex 1 is surrounded by two independent anionic ligands with N2O donor set, thus possesses a distorted octahedral coordination geometry. However, in complex 2, the Cd (Ⅱ) ion with bicapped-triangular prism geometry is coordinated with one neutral ligand HL, two bidentate nitrate anions and one methanol molecule. In addition, the thermal stability and luminescent properties of the complexes are also studied in detail. CCDC: 1424257, 1; 1424258, 2.
2016, 32(1): 167-174
doi: 10.11862/CJIC.2016.009
Abstract:
Two novel lanthanide metal complexes based on H2btpa ligand, namely {[Ln (btpa)(H2O)(OH)]·bpy}n (Ln=Tb (1), Pr (2), H2btpa=3′, 4′-bis (terazol-5′-yl) phenoxy) isophthalic acid, bpy=4, 4′-pyridine), have been synthesized and structurally characterized by elemental analyses, IR spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction analyses. They possess the same 2D network, which is constructed from binuclear lanthanide units cross-linked by btpa2- ligands via μ4:η1, η2, η1, η2 coordination mode with guest molecule bpy existing in the structure to form intermolecular hydrogen bond. Interestingly, the adjacent 2D networks are intercalated in a zipper fashion generating a 3D supramolecular structure through intermolecular hydrogen bonding. The luminescence experiments show that complex 1 exhibits typical TbⅢ-centered emissions in the visible region. CCDC: 1417525, 1; 1417526, 2.
Two novel lanthanide metal complexes based on H2btpa ligand, namely {[Ln (btpa)(H2O)(OH)]·bpy}n (Ln=Tb (1), Pr (2), H2btpa=3′, 4′-bis (terazol-5′-yl) phenoxy) isophthalic acid, bpy=4, 4′-pyridine), have been synthesized and structurally characterized by elemental analyses, IR spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction analyses. They possess the same 2D network, which is constructed from binuclear lanthanide units cross-linked by btpa2- ligands via μ4:η1, η2, η1, η2 coordination mode with guest molecule bpy existing in the structure to form intermolecular hydrogen bond. Interestingly, the adjacent 2D networks are intercalated in a zipper fashion generating a 3D supramolecular structure through intermolecular hydrogen bonding. The luminescence experiments show that complex 1 exhibits typical TbⅢ-centered emissions in the visible region. CCDC: 1417525, 1; 1417526, 2.
2016, 32(1): 175-183
doi: 10.11862/CJIC.2016.024
Abstract:
Two coordination polymers, namely {[Zn (timb)(BTEC)0.5]·H2O}n (1) and {[Cd (timb)(DPA)] ·H2O}n (2), have been obtained by the reaction of metal salt (zinc nitrate or cadmium nitrate), 1, 3, 5-tris (imidazol-1-yl) benzene (timb) with two aromatic carboxylic acids, 1, 2, 4, 5-benzenetetracarboxylic acid (H4BTEC) and diphenic acid (H2DPA). They were characterized by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. Complex 1 crystallizes in triclinic, space group P1 with a=0.991 32(9) nm, b=1.018 23(10) nm, c=1.112 45(11) nm, α=81.479 0(10)°, β=65.613 0(10)°, γ=62.318 0(10)°. Complex 2 belongs to monoclinic, space group C2/c with a=2.633 0(2) nm, b=0.841 96(8) nm, c=2.353 5(2) nm, β=98.027 0(10)°. Structural analyses reveal that complex 1 exhibits a novel three-dimensional (3D) (3, 4, 5)-connected framework with an unusual (4.63·86)2(42·84)(63)2 topology, whereas complex 2 possesses a one-dimensional (1D) single-wall metal-organic nanotube based on double helical chains. The results show that the nature of metal ions and the carboxylic building blocks play an important role in the formation of complexes with diverse structures. The luminescent properties of two complexes have also been investigated. CCDC: 1422833, 1; 1422832, 2.
Two coordination polymers, namely {[Zn (timb)(BTEC)0.5]·H2O}n (1) and {[Cd (timb)(DPA)] ·H2O}n (2), have been obtained by the reaction of metal salt (zinc nitrate or cadmium nitrate), 1, 3, 5-tris (imidazol-1-yl) benzene (timb) with two aromatic carboxylic acids, 1, 2, 4, 5-benzenetetracarboxylic acid (H4BTEC) and diphenic acid (H2DPA). They were characterized by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. Complex 1 crystallizes in triclinic, space group P1 with a=0.991 32(9) nm, b=1.018 23(10) nm, c=1.112 45(11) nm, α=81.479 0(10)°, β=65.613 0(10)°, γ=62.318 0(10)°. Complex 2 belongs to monoclinic, space group C2/c with a=2.633 0(2) nm, b=0.841 96(8) nm, c=2.353 5(2) nm, β=98.027 0(10)°. Structural analyses reveal that complex 1 exhibits a novel three-dimensional (3D) (3, 4, 5)-connected framework with an unusual (4.63·86)2(42·84)(63)2 topology, whereas complex 2 possesses a one-dimensional (1D) single-wall metal-organic nanotube based on double helical chains. The results show that the nature of metal ions and the carboxylic building blocks play an important role in the formation of complexes with diverse structures. The luminescent properties of two complexes have also been investigated. CCDC: 1422833, 1; 1422832, 2.
2016, 32(1): 184-190
doi: 10.11862/CJIC.2016.016
Abstract:
Two coordination polymers {[Co (BIDPT)(oba)(H2O)2]}n (1) and {[Co (BIDPT)(p-bdc)]·H2O}n (2) were synthesized by hydrothermal method using 4, 4′-bis (imidazol-l-yl) diphenyl thioether (BIDPT), 4, 4′-oxydibenzoic acid (H2oba), terephthalic acid (p-H2bdc) and Co (NO3)2·6H2O. The complexes were characterized by FT-IR, elemental analysis, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD) and their crystal structures were determined by single-crystal X-ray diffraction. Structural analyses reveal that complex 1 crystallizes in the monoclinic system, space group P2/c. Complex 2 crystallizes in the triclinic system, space group P1. Complexes 1 and 2 exhibit a two-dimensional (2D) corrugated layer structures. Through intermolecular hydrogen bonding, the two compounds are assembled into 3D supramolecular structures. Ultraviolet spectroscopy studies revealed that the two compounds exhibit ultraviolet adsorption in the solid state at room temperature. CCDC: 1058936, 1; 1420850, 2.
Two coordination polymers {[Co (BIDPT)(oba)(H2O)2]}n (1) and {[Co (BIDPT)(p-bdc)]·H2O}n (2) were synthesized by hydrothermal method using 4, 4′-bis (imidazol-l-yl) diphenyl thioether (BIDPT), 4, 4′-oxydibenzoic acid (H2oba), terephthalic acid (p-H2bdc) and Co (NO3)2·6H2O. The complexes were characterized by FT-IR, elemental analysis, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD) and their crystal structures were determined by single-crystal X-ray diffraction. Structural analyses reveal that complex 1 crystallizes in the monoclinic system, space group P2/c. Complex 2 crystallizes in the triclinic system, space group P1. Complexes 1 and 2 exhibit a two-dimensional (2D) corrugated layer structures. Through intermolecular hydrogen bonding, the two compounds are assembled into 3D supramolecular structures. Ultraviolet spectroscopy studies revealed that the two compounds exhibit ultraviolet adsorption in the solid state at room temperature. CCDC: 1058936, 1; 1420850, 2.
2016, 32(1): 9-17
doi: 10.11862/CJIC.2016.028
Abstract:
Three Metal-Organic Frameworks (MOFs) materials, namely, {[Co5(BETA)2(OH)2(H2O)2]·10H2O}n(1), {[Zn5(BETA)2(OH)2(H2O)2]·10H2O}n(2) and {[Mn2(BTCA)(H2O)3]·H2O}n (3), (H4BETA=1,2,4,5-benzene tetracarboxylic acid; H4BTCA=1,2,4,5-butane tetracarboxylic acid), have been solvothermally synthesized, and characterized by X-ray single crystal diffraction, IR spectrum, PL spectrum, and TG/DTG analyses. The results show that the three MOFs belong to monoclinic system, space group P21/n. Five-nuclear metal clusters in compound 1 and 2 are linked by BETA4- ligand to form 3D framework structure, and produce 1D channel with the pore size of 0.990 nm×1.307 nm along the a axis. The framework of compound 3 is consisted of Mn2+ ions with BTCA4- ligands forming 4,8-c network. CCDC: 1409602, 3; 1409603, 2; 1409601, 3.
Three Metal-Organic Frameworks (MOFs) materials, namely, {[Co5(BETA)2(OH)2(H2O)2]·10H2O}n(1), {[Zn5(BETA)2(OH)2(H2O)2]·10H2O}n(2) and {[Mn2(BTCA)(H2O)3]·H2O}n (3), (H4BETA=1,2,4,5-benzene tetracarboxylic acid; H4BTCA=1,2,4,5-butane tetracarboxylic acid), have been solvothermally synthesized, and characterized by X-ray single crystal diffraction, IR spectrum, PL spectrum, and TG/DTG analyses. The results show that the three MOFs belong to monoclinic system, space group P21/n. Five-nuclear metal clusters in compound 1 and 2 are linked by BETA4- ligand to form 3D framework structure, and produce 1D channel with the pore size of 0.990 nm×1.307 nm along the a axis. The framework of compound 3 is consisted of Mn2+ ions with BTCA4- ligands forming 4,8-c network. CCDC: 1409602, 3; 1409603, 2; 1409601, 3.
2016, 32(1): 18-24
doi: 10.11862/CJIC.2016.025
Abstract:
The collision dynamics processes of an energetic carbon ion to the Stone-Wales defect in graphene are investigated by using molecular dynamics method. We calculate the displacement threshold energy for the primary knock-on atom in Stone-Wales defect and the incident threshold energy for the projectile carbon ion prompting the target atom displacement, which are compared with the results of the perfect graphene. The energy transfer is studied by analyzing the time evolutions of the kinetic energies and potential energies of the primary knock-on atom and the incident ion. We find that the displacement threshold energy is 25.0 eV, which is the minimum kinetic energy for the primary knock-on atom to leave its original position and eventually escape from the graphene system. When the initial kinetic energy is 23.0 eV, the common C-C bond of the two heptagons in the Stone-Wales defect rotates 90° to form a perfect graphene structure. The minimum incident energy of the projectile required to drive the primary knock-on atom in the Stone-Wales defect to displace permanently from its original location is 41.0 eV.
The collision dynamics processes of an energetic carbon ion to the Stone-Wales defect in graphene are investigated by using molecular dynamics method. We calculate the displacement threshold energy for the primary knock-on atom in Stone-Wales defect and the incident threshold energy for the projectile carbon ion prompting the target atom displacement, which are compared with the results of the perfect graphene. The energy transfer is studied by analyzing the time evolutions of the kinetic energies and potential energies of the primary knock-on atom and the incident ion. We find that the displacement threshold energy is 25.0 eV, which is the minimum kinetic energy for the primary knock-on atom to leave its original position and eventually escape from the graphene system. When the initial kinetic energy is 23.0 eV, the common C-C bond of the two heptagons in the Stone-Wales defect rotates 90° to form a perfect graphene structure. The minimum incident energy of the projectile required to drive the primary knock-on atom in the Stone-Wales defect to displace permanently from its original location is 41.0 eV.
2016, 32(1): 34-42
doi: 10.11862/CJIC.2016.018
Abstract:
The Ca1-xSmxWO4 phosphors with different doping concentrations and different sintered temperatures were synthesized by hydrothermal method. The phase structure，morphology, luminescent properties and quantum efficiency of the as-synthesized samples were characterized by X-ray diffraction，fourier transform infrared spectroscopy, scanning electron microscope, fluorescence spectrophotometer respectively and Fluoromax-4. The results showed that all the phases were indexed to scheelite structure. The emission spectra of Ca1-xSmxWO4 phosphors exhibit three main peaks assigned to the 4G5/2→66HJ/2 (J=5，7，9) transitions of Sm3+ under 405 nm excited radiation, the dominating emission peaks at 566, 606, 650 nm. The luminescence intensity firstly increases with increasing of Sm3+ mole fraction, and then decreases. Experiments show that the best Sm3+ doping concentration is 1%. The energy transfer type between Sm3+ ions was determined to be the exchange interaction and the critical energy transfer distance (Dc) was calculated to be 2.46 nm.
The Ca1-xSmxWO4 phosphors with different doping concentrations and different sintered temperatures were synthesized by hydrothermal method. The phase structure，morphology, luminescent properties and quantum efficiency of the as-synthesized samples were characterized by X-ray diffraction，fourier transform infrared spectroscopy, scanning electron microscope, fluorescence spectrophotometer respectively and Fluoromax-4. The results showed that all the phases were indexed to scheelite structure. The emission spectra of Ca1-xSmxWO4 phosphors exhibit three main peaks assigned to the 4G5/2→66HJ/2 (J=5，7，9) transitions of Sm3+ under 405 nm excited radiation, the dominating emission peaks at 566, 606, 650 nm. The luminescence intensity firstly increases with increasing of Sm3+ mole fraction, and then decreases. Experiments show that the best Sm3+ doping concentration is 1%. The energy transfer type between Sm3+ ions was determined to be the exchange interaction and the critical energy transfer distance (Dc) was calculated to be 2.46 nm.
2016, 32(1): 43-48
doi: 10.11862/CJIC.2016.003
Abstract:
Two new metal-organic coordination polymers {[NiL(H2O)]·H2O}n (1), [CdL(phen)]n (2) (H2L=5-(4-(2,6-di(pyrizin-2-yl)pyridin-4-yl)phenoxy)isophthalic acid) have been synthesized under solvothermal conditions and characterized by single crystal X-ray diffraction analysis. Complex 1 features a (4,4)-connected 3D network. The carboxylate groups of the L2- ligands bridges two Ni(Ⅱ) ions into one 1D chain, then the neighboring chains are further interconnected by the N atoms of the L2- ligands to generate a 3D net. Complex 2 displays a (3,3)-connected 2D framework and further linked by π…π interactions between aromatic rings with a centroid-centroid distance of 0.365 2 nm into the final 3D net, in which the Cd(Ⅱ) is seven-coordinated in one-capped trigonol prismatic geometry. Thermogravimetric analyses (TGA) have been measured for 1 and 2. Luminescent properties of 2 were investigated. CCDC: 1406238, 1; 1406239, 2.
Two new metal-organic coordination polymers {[NiL(H2O)]·H2O}n (1), [CdL(phen)]n (2) (H2L=5-(4-(2,6-di(pyrizin-2-yl)pyridin-4-yl)phenoxy)isophthalic acid) have been synthesized under solvothermal conditions and characterized by single crystal X-ray diffraction analysis. Complex 1 features a (4,4)-connected 3D network. The carboxylate groups of the L2- ligands bridges two Ni(Ⅱ) ions into one 1D chain, then the neighboring chains are further interconnected by the N atoms of the L2- ligands to generate a 3D net. Complex 2 displays a (3,3)-connected 2D framework and further linked by π…π interactions between aromatic rings with a centroid-centroid distance of 0.365 2 nm into the final 3D net, in which the Cd(Ⅱ) is seven-coordinated in one-capped trigonol prismatic geometry. Thermogravimetric analyses (TGA) have been measured for 1 and 2. Luminescent properties of 2 were investigated. CCDC: 1406238, 1; 1406239, 2.
2016, 32(1): 56-62
doi: 10.11862/CJIC.2016.006
Abstract:
A novel colorimetric probe, 3, 5-dichlorosalicylaldehyde-o-rhodamine B hydrazone (L), for Cu2+ was designed, synthesized. Its structure was characterized with IR, 1H NMR, 13C NMR, elemental analysis and X-ray crystal diffraction. The binding property of the probe with Cu2+ was examined by UV-Vis spectroscopy. The result showed in acetonitrile/methenamine (pH 5.6) buffer system, when Cu2+ was added to the solution of 3, 5-dichloro-salicylaldehyde-o-rhodamine B hydrazone, a dramatic color change from colorless to rose red was observed, while the other metal ions did not cause noticeable changes, which indicates that 3, 5-dichlorosalicylaldehyde-o-rhodamine B hydrazone had a high sensitivity single selectivity colorimetric recognition for Cu2+. The detection limit for Cu2+ was 9.30×10-8 mol·L-1 by UV-Vis spectroscopy.
A novel colorimetric probe, 3, 5-dichlorosalicylaldehyde-o-rhodamine B hydrazone (L), for Cu2+ was designed, synthesized. Its structure was characterized with IR, 1H NMR, 13C NMR, elemental analysis and X-ray crystal diffraction. The binding property of the probe with Cu2+ was examined by UV-Vis spectroscopy. The result showed in acetonitrile/methenamine (pH 5.6) buffer system, when Cu2+ was added to the solution of 3, 5-dichloro-salicylaldehyde-o-rhodamine B hydrazone, a dramatic color change from colorless to rose red was observed, while the other metal ions did not cause noticeable changes, which indicates that 3, 5-dichlorosalicylaldehyde-o-rhodamine B hydrazone had a high sensitivity single selectivity colorimetric recognition for Cu2+. The detection limit for Cu2+ was 9.30×10-8 mol·L-1 by UV-Vis spectroscopy.
2016, 32(1): 63-68
doi: 10.11862/CJIC.2016.015
Abstract:
Ni1-xZnxFe2O4 ferrites (x=0, 0.3, 0.5, 0.7 and 1.0) nanoparticles have been achieved by the polyol process using triethylene glycol as a solvent and acetylacetonate metal salts as precursors. The structure, morphology, magnetic properties and magnetocaloric effect under alternating magnetic field of resultant particles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM). The results show that NiZn ferrites nanoparticles have uniform size and good dispersibility with approximate spherical shape. The average sizes are about 4~5 nm. The monodisperse NixZn1-xFe2O4 nano-particles show a typical ferrimagnetic behavior at room temperature. The saturation magnetization increases and then decreases with the increase of Ni2+ concentration. The maximum saturation magnetization with concentration of Ni2+ up to x=0.5 is determined to be 29.38 emu·g-1. The temperature of Ni0.5Zn0.5Fe2O4 ferrites can reach up to 313 K under a 382 kHz magnetic field which reveals its sufficient heating ability.
Ni1-xZnxFe2O4 ferrites (x=0, 0.3, 0.5, 0.7 and 1.0) nanoparticles have been achieved by the polyol process using triethylene glycol as a solvent and acetylacetonate metal salts as precursors. The structure, morphology, magnetic properties and magnetocaloric effect under alternating magnetic field of resultant particles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM). The results show that NiZn ferrites nanoparticles have uniform size and good dispersibility with approximate spherical shape. The average sizes are about 4~5 nm. The monodisperse NixZn1-xFe2O4 nano-particles show a typical ferrimagnetic behavior at room temperature. The saturation magnetization increases and then decreases with the increase of Ni2+ concentration. The maximum saturation magnetization with concentration of Ni2+ up to x=0.5 is determined to be 29.38 emu·g-1. The temperature of Ni0.5Zn0.5Fe2O4 ferrites can reach up to 313 K under a 382 kHz magnetic field which reveals its sufficient heating ability.
2016, 32(1): 69-73
doi: 10.11862/CJIC.2016.001
Abstract:
Through optimizing the experimental conditions (including solvent, solvothermal reaction temperature and time), NiFe2O4 magnetic nanomaterial with good crystallization and super paramagnetic performance, was prepared by one-step solvothermal method using Fe (NO3)3·9H2O and Ni (NO3)2·6H2O as raw materials and EtOH as solvent without adding any alkaline precipitation agent or high-temperature crystallization process. The results show that the solvents, H2O and (H2O+EtOH), are disadvantageous to the target magnetic species NiFe2O4.Under the condition of EtOH as solvent, the proper solvothermal temperature and reaction time must be guaranteed in order to obtain NiFe2O4 magnetic nanomaterial with high purity. The magnetic properties of prepared materials are related to the content of NiFe2O4 and its crystallization degree. The prominent advantages of this preparation method are of simpleness, speediness, low cost, free pollution from the source and friendly-environment. And the prepared materials have excellent magnetic performance.
Through optimizing the experimental conditions (including solvent, solvothermal reaction temperature and time), NiFe2O4 magnetic nanomaterial with good crystallization and super paramagnetic performance, was prepared by one-step solvothermal method using Fe (NO3)3·9H2O and Ni (NO3)2·6H2O as raw materials and EtOH as solvent without adding any alkaline precipitation agent or high-temperature crystallization process. The results show that the solvents, H2O and (H2O+EtOH), are disadvantageous to the target magnetic species NiFe2O4.Under the condition of EtOH as solvent, the proper solvothermal temperature and reaction time must be guaranteed in order to obtain NiFe2O4 magnetic nanomaterial with high purity. The magnetic properties of prepared materials are related to the content of NiFe2O4 and its crystallization degree. The prominent advantages of this preparation method are of simpleness, speediness, low cost, free pollution from the source and friendly-environment. And the prepared materials have excellent magnetic performance.
2016, 32(1): 74-80
doi: 10.11862/CJIC.2016.007
Abstract:
The mixed oxides based on layered double hydroxide (LDO) are novel solid base catalyst, and their modification and functionalization have received more and more interesting in the area of catalysis. In this paper, the hollow magnetic solid base catalyst has been (Fe3O4@LDO) synthesized by coating LDO onto the hollow Fe3O4 particles. The Fe3O4@LDO particles possess well defined core-shell structure with Mg-Al Mixed Oxides as the shell and hollow Fe3O4 particle as the core. Owing to its unique hollow structure, the Fe3O4@LDO particles possess high colloid stability, and showing promising application in homogeneous catalysis. In the Knoevenagel condensation of benzaldehyde with ethyl acetoacetate under solvent free conditions, the Fe3O4@LDO particles gave the highest activity with yield of 62% in 2 h, showing high catalytic activity. In the mean time, the Fe3O4@LDO particles have strong magnetic response, can be easily separated and recycled after a catalyst reaction.
The mixed oxides based on layered double hydroxide (LDO) are novel solid base catalyst, and their modification and functionalization have received more and more interesting in the area of catalysis. In this paper, the hollow magnetic solid base catalyst has been (Fe3O4@LDO) synthesized by coating LDO onto the hollow Fe3O4 particles. The Fe3O4@LDO particles possess well defined core-shell structure with Mg-Al Mixed Oxides as the shell and hollow Fe3O4 particle as the core. Owing to its unique hollow structure, the Fe3O4@LDO particles possess high colloid stability, and showing promising application in homogeneous catalysis. In the Knoevenagel condensation of benzaldehyde with ethyl acetoacetate under solvent free conditions, the Fe3O4@LDO particles gave the highest activity with yield of 62% in 2 h, showing high catalytic activity. In the mean time, the Fe3O4@LDO particles have strong magnetic response, can be easily separated and recycled after a catalyst reaction.
2016, 32(1): 81-88
doi: 10.11862/CJIC.2016.021
Abstract:
Three novel D-π-A type organic dye sensitizers based on BODIPY derivatives featured with BODIPY as π-conjugate bridge, N-phenylcarbazole linked BODIPY unit with different active positions as electron donor and cyanoacrylic acid as electron acceptor were designed and successfully synthesized. The structures of these synthetic dyes CB1~CB3 were characterized by 1H, 13C NMR and MALDI-TOF-MS. The photophysical properties, electrochemical behaviors and photovoltaic performances of these dyes were measured and the relationships between the structure and property were further studied by density functional theory calculations. The absorption spectral of CB1~CB3 ranged from 420 nm to 600 nm. Their LUMO and HOMO levels were located on about 3.7 eV and 5.2 eV respectively. CB2 exhibited more excellent photovoltaic performance than CB1 and CB3 due to the more planar structure and more suitable conjugation length, which resulting in broad absorption and better intramolecular electron transfer property. Under AM 1.5 (100 mW·cm-2) irradiation, CB2 sensitized solar cell give 1.49% total photoelectric conversion efficiency with open circuit voltage (Voc) 550 mV, short-circuit current density (Jsc) 3.71mA·cm-2 and fill factor (FF) 0.73.
Three novel D-π-A type organic dye sensitizers based on BODIPY derivatives featured with BODIPY as π-conjugate bridge, N-phenylcarbazole linked BODIPY unit with different active positions as electron donor and cyanoacrylic acid as electron acceptor were designed and successfully synthesized. The structures of these synthetic dyes CB1~CB3 were characterized by 1H, 13C NMR and MALDI-TOF-MS. The photophysical properties, electrochemical behaviors and photovoltaic performances of these dyes were measured and the relationships between the structure and property were further studied by density functional theory calculations. The absorption spectral of CB1~CB3 ranged from 420 nm to 600 nm. Their LUMO and HOMO levels were located on about 3.7 eV and 5.2 eV respectively. CB2 exhibited more excellent photovoltaic performance than CB1 and CB3 due to the more planar structure and more suitable conjugation length, which resulting in broad absorption and better intramolecular electron transfer property. Under AM 1.5 (100 mW·cm-2) irradiation, CB2 sensitized solar cell give 1.49% total photoelectric conversion efficiency with open circuit voltage (Voc) 550 mV, short-circuit current density (Jsc) 3.71mA·cm-2 and fill factor (FF) 0.73.
2016, 32(1): 89-95
doi: 10.11862/CJIC.2016.010
Abstract:
ZSM-5 nanosheets with Si/Al molar ratios of 18, 26 and 95 have been synthesized hydrothermally using [C18H37-N+(CH3)2-C6H12-N+(CH3)2-C6H13]Br2 as a template and then ion-exchanged with Cu2+ cations. The obtained Cu-ZSM-5 nanosheets were characterized by XRF, N2 adsorption-desorption, XRD, SEM, TEM, DRIFTS, H2-TPR, O2-TPD and CO-DRIFT. Their catalytic performance for N2O decomposition was investigated. The catalytic activity in terms of TOF for Cu-ZSM-5 nanosheets increases with the decreasing of the nSi/nAl, due to better reducibility of active Cu+ species, and better desorption capability of adsorbed oxygen on Cu-ZSM-5 nanosheets with lower nSi/nAl.
ZSM-5 nanosheets with Si/Al molar ratios of 18, 26 and 95 have been synthesized hydrothermally using [C18H37-N+(CH3)2-C6H12-N+(CH3)2-C6H13]Br2 as a template and then ion-exchanged with Cu2+ cations. The obtained Cu-ZSM-5 nanosheets were characterized by XRF, N2 adsorption-desorption, XRD, SEM, TEM, DRIFTS, H2-TPR, O2-TPD and CO-DRIFT. Their catalytic performance for N2O decomposition was investigated. The catalytic activity in terms of TOF for Cu-ZSM-5 nanosheets increases with the decreasing of the nSi/nAl, due to better reducibility of active Cu+ species, and better desorption capability of adsorbed oxygen on Cu-ZSM-5 nanosheets with lower nSi/nAl.
2016, 32(1): 96-102
doi: 10.11862/CJIC.2016.029
Abstract:
The conjugated Poly Schiff base (CPSB) was synthesized through condensation reaction between glutaraldehyde and p-phenylenediamine, then cross-linked with melamine to build a three-dimensional network structure, which was further doped with Fe3+ to form FeCl3 /CPSB composite with urchin-like structure. Meanwhile, the conductivity (σ), the real and imaginary parts of permittivity (ε′, ε″) and the dielectric loss tangent value (tanδε) occurred a significant increase and the Cole-Cole semicircle start from scratch, through comparing the initial and after 6 months value of CPSB with 0.02, 0.03, 0.04 mol Fe3+ doping content. The result displayed that ε″ was changed from a negative value to a positive value in 3.664×106~1.000×107 Hz after six months. Wherein, tanδε of composite with 0.04 mol Fe3+ doping content was increased from 0.02 to 6.13 and σ was increased from 7.15×10-7 S·cm-1 to 2.19×10-5 S·cm-1 in 102 Hz. The ε′ and ε″ were increased significantly as well. There are double relaxation mechanisms contributing the Debye relaxation to enhanced dielectric properties of the FeCl3/CPBS composite.
The conjugated Poly Schiff base (CPSB) was synthesized through condensation reaction between glutaraldehyde and p-phenylenediamine, then cross-linked with melamine to build a three-dimensional network structure, which was further doped with Fe3+ to form FeCl3 /CPSB composite with urchin-like structure. Meanwhile, the conductivity (σ), the real and imaginary parts of permittivity (ε′, ε″) and the dielectric loss tangent value (tanδε) occurred a significant increase and the Cole-Cole semicircle start from scratch, through comparing the initial and after 6 months value of CPSB with 0.02, 0.03, 0.04 mol Fe3+ doping content. The result displayed that ε″ was changed from a negative value to a positive value in 3.664×106~1.000×107 Hz after six months. Wherein, tanδε of composite with 0.04 mol Fe3+ doping content was increased from 0.02 to 6.13 and σ was increased from 7.15×10-7 S·cm-1 to 2.19×10-5 S·cm-1 in 102 Hz. The ε′ and ε″ were increased significantly as well. There are double relaxation mechanisms contributing the Debye relaxation to enhanced dielectric properties of the FeCl3/CPBS composite.
2016, 32(1): 103-110
doi: 10.11862/CJIC.2016.011
Abstract:
The adsorption isotherms of bovine serum albumin (BSA) on calcium oxalate monohydrate (COM) and calcium oxalate dehydrate (COD) crystals with a size of 100 nm and 3 μm were detected, and Zeta potential of the crystals after adsorption of various concentration of BSA was measured. Adsorption quality change of BSA at different pH value were also measured. Results showed that the adsorption quality of BSA were positively related to the specific surface area of crystals, that was, following the order: COD-100nm > COM-100 nm≥COD-3 μm > COM-3 μm. However, after surface area normalization, the adsorption order was COD-3 μm > COM-3 μm > COM-100 nm > COD-100 nm. It indicated that the crystal water and charge density on crystal surface of COM and COD also affected BSA adsorption. These adsorption isotherms were fitted better with Langmuir model, indicating a monolayer adsorption of BSA on micron/nano COD and COM surface. The isoelectric point of the four crystals followed an order: COM-100 nm (7.2) > COD-100 nm (6.7)≥COM-3 μm (4.7) > COD-3 μm (4.3), which indicated more serious aggregation of nanocrystals under pathophysiological conditions (pH≈6.3). The maximum BSA adsorption occurred at around isoelectric point of BSA (pH=4.8). The adsorption of BSA on micron/nano COM is related to the specific surface area of crystals, its surface charge, crystal aggregation, crystal water number, and the pH value of system. These results can help to clarify the effect of various urine microcrystalline and urine proteins on the formation of CaOx stones.
The adsorption isotherms of bovine serum albumin (BSA) on calcium oxalate monohydrate (COM) and calcium oxalate dehydrate (COD) crystals with a size of 100 nm and 3 μm were detected, and Zeta potential of the crystals after adsorption of various concentration of BSA was measured. Adsorption quality change of BSA at different pH value were also measured. Results showed that the adsorption quality of BSA were positively related to the specific surface area of crystals, that was, following the order: COD-100nm > COM-100 nm≥COD-3 μm > COM-3 μm. However, after surface area normalization, the adsorption order was COD-3 μm > COM-3 μm > COM-100 nm > COD-100 nm. It indicated that the crystal water and charge density on crystal surface of COM and COD also affected BSA adsorption. These adsorption isotherms were fitted better with Langmuir model, indicating a monolayer adsorption of BSA on micron/nano COD and COM surface. The isoelectric point of the four crystals followed an order: COM-100 nm (7.2) > COD-100 nm (6.7)≥COM-3 μm (4.7) > COD-3 μm (4.3), which indicated more serious aggregation of nanocrystals under pathophysiological conditions (pH≈6.3). The maximum BSA adsorption occurred at around isoelectric point of BSA (pH=4.8). The adsorption of BSA on micron/nano COM is related to the specific surface area of crystals, its surface charge, crystal aggregation, crystal water number, and the pH value of system. These results can help to clarify the effect of various urine microcrystalline and urine proteins on the formation of CaOx stones.
2016, 32(1): 111-116
doi: 10.11862/CJIC.2016.005
Abstract:
CdS thin films were deposited on soda-lime glass (SLG) substrates by chemical bath deposition (CBD). Effects of intrinsic defects on electrical and optical properties of CdS thin films deposited at various concentration of CdSO4 in solution were systemically investigated. Photoluminescence (PL), UV-Visible spectrophotometer and Hall-effect system were used to study intrinsic defects, optical and electrical properties of CdS thin films. Two intrinsic defects (Cdi and VS) were found to be existed in CdS films using photoluminescence (PL), and these defects are donor defects. It is found that the intrinsic defects (VS) decrease with the reduction of CdSO4 concentration. The variation of the intrinsic defects results in the shifts of transmittance and conductivity. According to the related equations of transmittance, it is indicated that the transmittance is inversely proportional to conductivity of semiconductor materials. Therefore, the decrease of donor defects (VS) results in the reduction of conductivity and significant increase of the transmittance of CdS thin films, well supporting our experimental results.
CdS thin films were deposited on soda-lime glass (SLG) substrates by chemical bath deposition (CBD). Effects of intrinsic defects on electrical and optical properties of CdS thin films deposited at various concentration of CdSO4 in solution were systemically investigated. Photoluminescence (PL), UV-Visible spectrophotometer and Hall-effect system were used to study intrinsic defects, optical and electrical properties of CdS thin films. Two intrinsic defects (Cdi and VS) were found to be existed in CdS films using photoluminescence (PL), and these defects are donor defects. It is found that the intrinsic defects (VS) decrease with the reduction of CdSO4 concentration. The variation of the intrinsic defects results in the shifts of transmittance and conductivity. According to the related equations of transmittance, it is indicated that the transmittance is inversely proportional to conductivity of semiconductor materials. Therefore, the decrease of donor defects (VS) results in the reduction of conductivity and significant increase of the transmittance of CdS thin films, well supporting our experimental results.
2016, 32(1): 117-123
doi: 10.11862/CJIC.2016.020
Abstract:
Silica/alumina composite aerogels with good heat resistance and formability were prepared by a sol-gel method combined with the ethanol supercritical fluid drying technique using aluminum trisec butoxide and trimethylethoxysilane (TMEO) as precursors. Transmission electron microscope, N2 adsorption analyzer, fourier transform infrared spectroscope, X-ray diffraction and hot disk thermal analyzer were used to characterize the morphology, pore structure, surface groups, phases, thermal properties, etc. The-Si-(CH3)3 groups were introduced onto the alumina nanoparticles by adding TMEO during sol-gel process. It is demonstrated that these groups would produce SiO2 nanoparticles, which effectively restricted the crystal growth of Al2O3 nanoparticles and led to the excellent heat resistance of the composite aerogels. The linear shrinkage of the obtained composite aerogel was as low as 16% and the corresponding specific surface area was as high as 141 m2·g-1 after heat treatment at 1 200 ℃. This would further contribute to the wide application of aerogels on high-temperature thermal insulation, adsorption, catalysis, etc.
Silica/alumina composite aerogels with good heat resistance and formability were prepared by a sol-gel method combined with the ethanol supercritical fluid drying technique using aluminum trisec butoxide and trimethylethoxysilane (TMEO) as precursors. Transmission electron microscope, N2 adsorption analyzer, fourier transform infrared spectroscope, X-ray diffraction and hot disk thermal analyzer were used to characterize the morphology, pore structure, surface groups, phases, thermal properties, etc. The-Si-(CH3)3 groups were introduced onto the alumina nanoparticles by adding TMEO during sol-gel process. It is demonstrated that these groups would produce SiO2 nanoparticles, which effectively restricted the crystal growth of Al2O3 nanoparticles and led to the excellent heat resistance of the composite aerogels. The linear shrinkage of the obtained composite aerogel was as low as 16% and the corresponding specific surface area was as high as 141 m2·g-1 after heat treatment at 1 200 ℃. This would further contribute to the wide application of aerogels on high-temperature thermal insulation, adsorption, catalysis, etc.
