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2013 Volume 29 Issue 4
2013, 29(4): 659-664
doi: 10.3969/j.issn.1001-4861.2013.00.072
Abstract:
α-TeO2:Tm3+/Er3+/Yb3+ and β-TeO2:Tm3+/Er3+/Yb3+ nanoparticles with Li+ doping had been prepared via a hydrothermal method. The nanoparticles were characterized by X-ray diffraction, transmission electron microscopy and upconversion luminescence spectra. The results indicated that the doping of Li+ ions does not change the crystal form and structure of the as-prepared nanoparticles basically. The as-prepared nanoparticles showed the blue emission (476 nm), green emissions (525 nm, 545 nm) and red emissions (659 nm, 667 nm) under 980 nm near-infrared light excitation, respectively, corresponding to energy level transition of 1G4→3H6 of Tm3+ ions, 2H11/2 →4I15/2 and 4S3/2→4I15/2 of Er3+ ions, 4F9/2→4I15/2 of Er3+ ions and 3F2→3H6 of Tm3+ ions. The results also indicated that doping of Li+ ions can increase the luminous intensity of the white light system, and it does not change the white color of the nanoparticles basically. In addition, the upconversion luminescence mechanism of the nanoparticles was analyzed.
α-TeO2:Tm3+/Er3+/Yb3+ and β-TeO2:Tm3+/Er3+/Yb3+ nanoparticles with Li+ doping had been prepared via a hydrothermal method. The nanoparticles were characterized by X-ray diffraction, transmission electron microscopy and upconversion luminescence spectra. The results indicated that the doping of Li+ ions does not change the crystal form and structure of the as-prepared nanoparticles basically. The as-prepared nanoparticles showed the blue emission (476 nm), green emissions (525 nm, 545 nm) and red emissions (659 nm, 667 nm) under 980 nm near-infrared light excitation, respectively, corresponding to energy level transition of 1G4→3H6 of Tm3+ ions, 2H11/2 →4I15/2 and 4S3/2→4I15/2 of Er3+ ions, 4F9/2→4I15/2 of Er3+ ions and 3F2→3H6 of Tm3+ ions. The results also indicated that doping of Li+ ions can increase the luminous intensity of the white light system, and it does not change the white color of the nanoparticles basically. In addition, the upconversion luminescence mechanism of the nanoparticles was analyzed.
2013, 29(4): 665-670
doi: 10.3969/j.issn.1001-4861.2013.00.064
Abstract:
Structural modification of the phosphor host plays a key role in the optimization of the luminescence properties of the optical materials, and it becomes the important research field for the exploration of the relationship between the solid structure and its property. The Y2SiO5 host is selected as the model to be substituted by the Si/Al or Si/P, and the [AlO4] and [PO4] tetragons are used to replace the [SiO4], so that a series of compounds with the chemical formula of Y1.95SiO5:0.05Ce3+, Y1.95Si1-xAlxO5-xFx:0.05Ce3+ (x=0.05, x=0.1, x=0.2, x=0.4, and x=1), Y1.95-yCaySi1-yPyO5:0.05Ce3+ (y=0, y=0.02, y=0.04, y=0.06, y=0.08, and y=0.2) phosphors were designed and successfully obtained. XRD patterns showed that the diffraction peaks of both Y1.95Si1-xAlxO5-xFx:0.05Ce3+ and Y1.95-yCaySi1-yPyO5:0.05Ce3+ matched well with the standard patterns of Y2SiO5. Photoluminescence investigations indicated that the emission intensities had been increased to a great extent compared with that of Y2SiO5. A slight blue-shift was also observed in the emission spectra of Y1.95Si1-xAlxO5-xFx:0.05Ce3+ and Y1.95-yCaySi1-yPyO5:0.05Ce3+. Moreover, decay curves of Y1.95Si1-xAlxO5-xFx:0.05Ce3+ and Y1.95-yCaySi1-yPyO5:0.05Ce3+ confirmed that there are similar chemical environment for the Ce3+ luminescence.
Structural modification of the phosphor host plays a key role in the optimization of the luminescence properties of the optical materials, and it becomes the important research field for the exploration of the relationship between the solid structure and its property. The Y2SiO5 host is selected as the model to be substituted by the Si/Al or Si/P, and the [AlO4] and [PO4] tetragons are used to replace the [SiO4], so that a series of compounds with the chemical formula of Y1.95SiO5:0.05Ce3+, Y1.95Si1-xAlxO5-xFx:0.05Ce3+ (x=0.05, x=0.1, x=0.2, x=0.4, and x=1), Y1.95-yCaySi1-yPyO5:0.05Ce3+ (y=0, y=0.02, y=0.04, y=0.06, y=0.08, and y=0.2) phosphors were designed and successfully obtained. XRD patterns showed that the diffraction peaks of both Y1.95Si1-xAlxO5-xFx:0.05Ce3+ and Y1.95-yCaySi1-yPyO5:0.05Ce3+ matched well with the standard patterns of Y2SiO5. Photoluminescence investigations indicated that the emission intensities had been increased to a great extent compared with that of Y2SiO5. A slight blue-shift was also observed in the emission spectra of Y1.95Si1-xAlxO5-xFx:0.05Ce3+ and Y1.95-yCaySi1-yPyO5:0.05Ce3+. Moreover, decay curves of Y1.95Si1-xAlxO5-xFx:0.05Ce3+ and Y1.95-yCaySi1-yPyO5:0.05Ce3+ confirmed that there are similar chemical environment for the Ce3+ luminescence.
2013, 29(4): 671-676
doi: 10.3969/j.issn.1001-4861.2013.00.146
Abstract:
A coordination polymer of MnⅡ with flexible ligands, namely [Mn(pda)(bpp)] (1) (H2pda=1,3-phenyl-enediacetic acid, bpp=1,3-bi(4-pyridyl)propane), was synthesized and characterized by single-crystal X-ray diffraction, elemental analysis and IR spectroscopy. The results of structure characterization indicate that the complex crystallizes in the orthorhombic space group Pnna with a=1.965 2(6) nm, b=1.103 3(4) nm, c=0.963 9(3) nm, α=β=γ=90.0°, V=2.089 8(12) nm3, Z=4, Dc=1.416 Mg·m-3, μ=0.664 mm-1, F(000)=924, and final R1=0.040 2, wR2=0.133 2. The crystal structure of complex 1 consists of one MnⅡ, one 1,3-pda ligand and one bpp ligand. The bpp ligands bridge the MnⅡ ions to form a one-dimensional(1D) right-handed helical chain along the crystallographic b direction. Moreover, these helical chains are united together through the 1,3-pda ligands to afford a two-dimensional(2D) helical layer. Further investigation of this 2D structure suggests that the MnⅡ centers are connected to each other by bpp to afford a 1D zigzag chain along the crystallographic c direction. The 1D zigzag chains are interlinked by the 1,3-pda anions, constituting step-shaped 2D (4,4) network. In addition, thermal stability and electrochemistry of 1 have also been studied. CCDC: 885051.
A coordination polymer of MnⅡ with flexible ligands, namely [Mn(pda)(bpp)] (1) (H2pda=1,3-phenyl-enediacetic acid, bpp=1,3-bi(4-pyridyl)propane), was synthesized and characterized by single-crystal X-ray diffraction, elemental analysis and IR spectroscopy. The results of structure characterization indicate that the complex crystallizes in the orthorhombic space group Pnna with a=1.965 2(6) nm, b=1.103 3(4) nm, c=0.963 9(3) nm, α=β=γ=90.0°, V=2.089 8(12) nm3, Z=4, Dc=1.416 Mg·m-3, μ=0.664 mm-1, F(000)=924, and final R1=0.040 2, wR2=0.133 2. The crystal structure of complex 1 consists of one MnⅡ, one 1,3-pda ligand and one bpp ligand. The bpp ligands bridge the MnⅡ ions to form a one-dimensional(1D) right-handed helical chain along the crystallographic b direction. Moreover, these helical chains are united together through the 1,3-pda ligands to afford a two-dimensional(2D) helical layer. Further investigation of this 2D structure suggests that the MnⅡ centers are connected to each other by bpp to afford a 1D zigzag chain along the crystallographic c direction. The 1D zigzag chains are interlinked by the 1,3-pda anions, constituting step-shaped 2D (4,4) network. In addition, thermal stability and electrochemistry of 1 have also been studied. CCDC: 885051.
2013, 29(4): 677-688
doi: 10.3969/j.issn.1001-4861.2013.00.118
Abstract:
Mesoporous silica was prepared by using hexadecyl trimethyl ammonium bromide (CTAB) as the template, tetraethoxysilane (tetraethylorthosilicate, TEOS) as the silicon source and nitric acid as the hydrolysis catalyst. The obtained sample was then modified via post grafting method. The mesoporous silica before and after modification was characterized by IR, DTA-TG, XRD, SEM, elemental analysis, micro-electrophoresis and N2 adsorption-desorption. The results show that the mesoporous silica has been modified by amino-groups, the material after modification still belongs to a family of mesoporous materials in spite of a slight decrease in the order degree. The surface area, pore size and pore volume become smaller, and the isoelectric point is decreased from 2.74 to 4.75 after the modification. The commercial Novozymes laccase is successfully immobilized in the inner surface of amino-functionalized mesoporous silica in this work by using glutaraldehyde as the crosslinking agent. The conditions of immobilization on amino-functionalized mesoporous silica were optimized by means of orthogonal experimental designs. The results show that the operational stability of the immobilized enzyme is significantly improved in comparison with the free enzyme.
Mesoporous silica was prepared by using hexadecyl trimethyl ammonium bromide (CTAB) as the template, tetraethoxysilane (tetraethylorthosilicate, TEOS) as the silicon source and nitric acid as the hydrolysis catalyst. The obtained sample was then modified via post grafting method. The mesoporous silica before and after modification was characterized by IR, DTA-TG, XRD, SEM, elemental analysis, micro-electrophoresis and N2 adsorption-desorption. The results show that the mesoporous silica has been modified by amino-groups, the material after modification still belongs to a family of mesoporous materials in spite of a slight decrease in the order degree. The surface area, pore size and pore volume become smaller, and the isoelectric point is decreased from 2.74 to 4.75 after the modification. The commercial Novozymes laccase is successfully immobilized in the inner surface of amino-functionalized mesoporous silica in this work by using glutaraldehyde as the crosslinking agent. The conditions of immobilization on amino-functionalized mesoporous silica were optimized by means of orthogonal experimental designs. The results show that the operational stability of the immobilized enzyme is significantly improved in comparison with the free enzyme.
2013, 29(4): 689-696
doi: 10.3969/j.issn.1001-4861.2013.00.143
Abstract:
The activated carbon supported CoB catalysts were prepared by using impregnation-reduction method (denoted as CoB/C-Imp) and electroless deposition method (denoted as CoB/C-ED), respectively. The catalytic properties were studied on the hydrolysis of NaBH4 aqueous solution. The catalytic activity of CoB/C-ED, CoB/C-Imp and unsupported CoB was 2 022, 2 503 and 1 351 mL·min-1·g-1 (Co), respectively. After 5 cycles, the CoB/C-ED could retain 70% initial activity, but CoB/C-Imp and unsupported CoB could only retain 30% and 10% initial activity. The CoB/C-ED shows the best catalytic performance. Furthermore, no obvious decrease in the activity is observed for CoB/C-ED even after it is exposed to air for 30 days, this good anti-oxidation property is favorable for storage and use. Further physicochemical characterization of these catalysts reveals that the unsupported CoB is easily agglomerated and the size of the secondary particles is in the range of 400~800 nm. After CoB supported on carbon, the agglomeration is greatly restrained. The dispersion of CoB for the CoB/C catalysts is improved compared to the unsupported CoB. The support could also reduce the agglomeration of CoB particles during the catalytic reaction. The CoB particles combine much stronger with the activated carbon support for the CoB/C-ED catalyst, thus resulting in better dispersion and stability, and lesser leaching.
The activated carbon supported CoB catalysts were prepared by using impregnation-reduction method (denoted as CoB/C-Imp) and electroless deposition method (denoted as CoB/C-ED), respectively. The catalytic properties were studied on the hydrolysis of NaBH4 aqueous solution. The catalytic activity of CoB/C-ED, CoB/C-Imp and unsupported CoB was 2 022, 2 503 and 1 351 mL·min-1·g-1 (Co), respectively. After 5 cycles, the CoB/C-ED could retain 70% initial activity, but CoB/C-Imp and unsupported CoB could only retain 30% and 10% initial activity. The CoB/C-ED shows the best catalytic performance. Furthermore, no obvious decrease in the activity is observed for CoB/C-ED even after it is exposed to air for 30 days, this good anti-oxidation property is favorable for storage and use. Further physicochemical characterization of these catalysts reveals that the unsupported CoB is easily agglomerated and the size of the secondary particles is in the range of 400~800 nm. After CoB supported on carbon, the agglomeration is greatly restrained. The dispersion of CoB for the CoB/C catalysts is improved compared to the unsupported CoB. The support could also reduce the agglomeration of CoB particles during the catalytic reaction. The CoB particles combine much stronger with the activated carbon support for the CoB/C-ED catalyst, thus resulting in better dispersion and stability, and lesser leaching.
2013, 29(4): 697-700
doi: 10.3969/j.issn.1001-4861.2013.00.128
Abstract:
The Ag(Ⅰ) complex of tebuconazole [AgL2]NO3(L=(RS)-1-(4-chloro-phenyl)-4,4-dimethyl-3-(1,2,4-triazole-1-ylmethyl)pentan-3-ol), tebuconazole) was synthesized and characterized by elemental analysis, IR, single crystal X-ray diffraction. The crystal is in the monoclinic system, space group C2/c, with cell parameters: a=3.698 9(7) nm, b=0.902 8(2) nm, c=1.122 8(2) nm, β=103.66(13)°, V=3.643 3(13) nm3, Dc=1.432 g·cm-3, Z=4, F(000)=1 624, μ=0.748 mm-1. The metal atoms are bridged by L to form coordination chains, which are linked by O-H…N hydrogen bonds to form a two-dimensional structure. The sterilization/disinfectant effect of tebuconazole and its silver complex to the Gibberella nicotiancola and Apple black fruit rot and the regulatory role to wheat growth were studied. The results show that [AgL2]NO3 is ineffective to the germination and growth on wheat, while it is active to inhibit Gibberella nicotiancola and Apple black fruit rot. CCDC: 917713.
The Ag(Ⅰ) complex of tebuconazole [AgL2]NO3(L=(RS)-1-(4-chloro-phenyl)-4,4-dimethyl-3-(1,2,4-triazole-1-ylmethyl)pentan-3-ol), tebuconazole) was synthesized and characterized by elemental analysis, IR, single crystal X-ray diffraction. The crystal is in the monoclinic system, space group C2/c, with cell parameters: a=3.698 9(7) nm, b=0.902 8(2) nm, c=1.122 8(2) nm, β=103.66(13)°, V=3.643 3(13) nm3, Dc=1.432 g·cm-3, Z=4, F(000)=1 624, μ=0.748 mm-1. The metal atoms are bridged by L to form coordination chains, which are linked by O-H…N hydrogen bonds to form a two-dimensional structure. The sterilization/disinfectant effect of tebuconazole and its silver complex to the Gibberella nicotiancola and Apple black fruit rot and the regulatory role to wheat growth were studied. The results show that [AgL2]NO3 is ineffective to the germination and growth on wheat, while it is active to inhibit Gibberella nicotiancola and Apple black fruit rot. CCDC: 917713.
2013, 29(4): 701-708
doi: 10.3969/j.issn.1001-4861.2013.00.135
Abstract:
Based on 2, 2′:6′, 2″-terpyridine (L1), five N,N,N-tridentate ligands, namely 4′-carbazol-9-yl-2,2′:6′,2″-terpyridine (L2), 4′-diphenylamino-2,2′:6′,2″-terpyridine (L3), 4′-bis(4-tert-butylphenyl)-amino-2,2′:6′,2″-terpyridine (L4), 4′-(1-naphthalenyl-N-phenyl)amino-2,2′:6′,2″-terpyridine (L5), 4′-(2-naphthalenyl-N-phenyl)amino-2,2′:6′,2″-terpyridine (L6), have been successfully synthesized. Employing 2-thenoyltrifluoroacetone (HTTA) and L1-L6 as the sensitizing ligands, a series of europium (Ⅲ) complexes (Eu(TTA)3L1-Eu(TTA)3L6) have been obtained. All the europium (Ⅲ) complexes show red characteristic emission of Eu(Ⅲ) 5D0-7FJ(J=0,1,2,3,4). The introduction of hole transport moieties improves the UV-Vis absorption and luminescence intensities of the europium(Ⅲ) complexes, and the carbazole containing complex Eu(TTA)3L2 exhibits the highest intensity and longest lifetime.
Based on 2, 2′:6′, 2″-terpyridine (L1), five N,N,N-tridentate ligands, namely 4′-carbazol-9-yl-2,2′:6′,2″-terpyridine (L2), 4′-diphenylamino-2,2′:6′,2″-terpyridine (L3), 4′-bis(4-tert-butylphenyl)-amino-2,2′:6′,2″-terpyridine (L4), 4′-(1-naphthalenyl-N-phenyl)amino-2,2′:6′,2″-terpyridine (L5), 4′-(2-naphthalenyl-N-phenyl)amino-2,2′:6′,2″-terpyridine (L6), have been successfully synthesized. Employing 2-thenoyltrifluoroacetone (HTTA) and L1-L6 as the sensitizing ligands, a series of europium (Ⅲ) complexes (Eu(TTA)3L1-Eu(TTA)3L6) have been obtained. All the europium (Ⅲ) complexes show red characteristic emission of Eu(Ⅲ) 5D0-7FJ(J=0,1,2,3,4). The introduction of hole transport moieties improves the UV-Vis absorption and luminescence intensities of the europium(Ⅲ) complexes, and the carbazole containing complex Eu(TTA)3L2 exhibits the highest intensity and longest lifetime.
2013, 29(4): 709-714
doi: 10.3969/j.issn.1001-4861.2013.00.110
Abstract:
Phase change in aluminoborosilicate glass and effect on leaching behavior were studied with different mass fraction of CeO2 via characterization methods of XRD, XPS, SEM and ICP-MS. The results showed that: In glass network structure the molar ratio of quadrivalence Ce and trivalent Ce was 9.25:1. And when mass fraction of CeO2 met or exceeded 7%, the cerianite began to be precipitated in glass. With mass fraction of CeO2 increasing, rCe of glass decreased at first and then increased in 1 day, and showed trend to decrease in 28 day. However, in the same mass fraction of CeO2, rCe gradually decreased with the prolongation of leaching time. And rCe of the glass sample bE stabilized lower than 4×10-6 g·m-2·d-1 after 7 day with 9wt% CeO2. The leaching behavior was excellent. Hence, controlling CeO2 precipitated within a certain range could be superior to completely dissolving one in glass on leaching behavior.
Phase change in aluminoborosilicate glass and effect on leaching behavior were studied with different mass fraction of CeO2 via characterization methods of XRD, XPS, SEM and ICP-MS. The results showed that: In glass network structure the molar ratio of quadrivalence Ce and trivalent Ce was 9.25:1. And when mass fraction of CeO2 met or exceeded 7%, the cerianite began to be precipitated in glass. With mass fraction of CeO2 increasing, rCe of glass decreased at first and then increased in 1 day, and showed trend to decrease in 28 day. However, in the same mass fraction of CeO2, rCe gradually decreased with the prolongation of leaching time. And rCe of the glass sample bE stabilized lower than 4×10-6 g·m-2·d-1 after 7 day with 9wt% CeO2. The leaching behavior was excellent. Hence, controlling CeO2 precipitated within a certain range could be superior to completely dissolving one in glass on leaching behavior.
2013, 29(4): 715-722
doi: 10.3969/j.issn.1001-4861.2013.00.125
Abstract:
New SbxZn1-xO1+x/2 and its composites with chitosan (CS) were prepared by the method of Sol-Gel. The phase structures, composition and morphologies of the samples were characterized by the X-ray diffraction (XRD), the Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The antibacterial properties of the samples were studied on Escherichia coli, Candida albicans and Staphylococcus aureus. The results showed that the antibacterial activities of the SbxZn1-xO1+x/2 were better than that of ZnO. In which, sample of x=0.05(SZ)had the best antibacterial activities. The SZ/CS composites were significantly better than each component in the antibacterial activity, and reached to the optimum when the mass ratio of SZ and CS was up to 2:1.
New SbxZn1-xO1+x/2 and its composites with chitosan (CS) were prepared by the method of Sol-Gel. The phase structures, composition and morphologies of the samples were characterized by the X-ray diffraction (XRD), the Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The antibacterial properties of the samples were studied on Escherichia coli, Candida albicans and Staphylococcus aureus. The results showed that the antibacterial activities of the SbxZn1-xO1+x/2 were better than that of ZnO. In which, sample of x=0.05(SZ)had the best antibacterial activities. The SZ/CS composites were significantly better than each component in the antibacterial activity, and reached to the optimum when the mass ratio of SZ and CS was up to 2:1.
2013, 29(4): 723-728
doi: 10.3969/j.issn.1001-4861.2013.00.061
Abstract:
Al-doped ZnO thin films (AZO) fabrication technique with low cost, large area, high deposition rate, well uniformity and excellent optical and electrical properties has been one of the most important aims in the transparent conductive oxide films research field. AZO thin films were grown on the glass substrates by cold-wall aerosol-assisted chemical vapour deposition (AACVD) method in this paper. Structural, optical and electrical properties of AZO films grown at different substrate temperature were investigated in detail. The samples were tested by X-Ray Diffraction, Atomic Force Microscopy, UV-Vis and Photoluminescence Spectroscopy. Results indicate that influence of the substrate temperature on the preferred orientation growth of AZO films appears undulant change during the course of AZO film deposited by AACVD. Distinct electrical properties transition takes place at around 400℃. Optical properties and preferred orientation growth of the ZnO films transition take place at around 450℃. Microcosmic mechanism was discussed that the effect of substrate temperature on the structural, optical and electrical properties of AZO films grown by AACVD method. Sheet resistance and the average transmittances in the visible regions of AZO films grown at 400℃ is about 190 Ω/□, 80% respectively.
Al-doped ZnO thin films (AZO) fabrication technique with low cost, large area, high deposition rate, well uniformity and excellent optical and electrical properties has been one of the most important aims in the transparent conductive oxide films research field. AZO thin films were grown on the glass substrates by cold-wall aerosol-assisted chemical vapour deposition (AACVD) method in this paper. Structural, optical and electrical properties of AZO films grown at different substrate temperature were investigated in detail. The samples were tested by X-Ray Diffraction, Atomic Force Microscopy, UV-Vis and Photoluminescence Spectroscopy. Results indicate that influence of the substrate temperature on the preferred orientation growth of AZO films appears undulant change during the course of AZO film deposited by AACVD. Distinct electrical properties transition takes place at around 400℃. Optical properties and preferred orientation growth of the ZnO films transition take place at around 450℃. Microcosmic mechanism was discussed that the effect of substrate temperature on the structural, optical and electrical properties of AZO films grown by AACVD method. Sheet resistance and the average transmittances in the visible regions of AZO films grown at 400℃ is about 190 Ω/□, 80% respectively.
2013, 29(4): 729-734
doi: 10.3969/j.issn.1001-4861.2013.00.120
Abstract:
The highly ordered TiO2 nanotube arrays films were fabricated by anodic oxidation of titanium foil substrates. And then, Cu2O particles were loaded on TiO2 nanotube arrays via galvanostatic pulse electrodeposition. As a result, Cu2O-TiO2 nanotube arrays heterojunction composite films were obtained. The influence of the electrolyte agitation methods (standing, magnetic agitating and ultrasonic stirring) during the processing of depositing Cu2O on the morphology and microstructure of the composite films were investigated by X-ray diffraction(XRD), field emitting scanning electron microscopy(FESEM) and transmission electron microscopy(TEM). The results show that the electrolyte agitation methods would affect the ion diffussion and local chemical environment in the processing of depositing Cu2O, which results in the morphologies evolution of Cu2O particles. The diffuse reflectance UV-Vis absorption spectra and the photocurrent properties measurements show that the prepared Cu2O-TiO2 nanotube arrays composite films exhibit remarkable visible light responses under visible light illumination.
The highly ordered TiO2 nanotube arrays films were fabricated by anodic oxidation of titanium foil substrates. And then, Cu2O particles were loaded on TiO2 nanotube arrays via galvanostatic pulse electrodeposition. As a result, Cu2O-TiO2 nanotube arrays heterojunction composite films were obtained. The influence of the electrolyte agitation methods (standing, magnetic agitating and ultrasonic stirring) during the processing of depositing Cu2O on the morphology and microstructure of the composite films were investigated by X-ray diffraction(XRD), field emitting scanning electron microscopy(FESEM) and transmission electron microscopy(TEM). The results show that the electrolyte agitation methods would affect the ion diffussion and local chemical environment in the processing of depositing Cu2O, which results in the morphologies evolution of Cu2O particles. The diffuse reflectance UV-Vis absorption spectra and the photocurrent properties measurements show that the prepared Cu2O-TiO2 nanotube arrays composite films exhibit remarkable visible light responses under visible light illumination.
2013, 29(4): 735-738
doi: 10.3969/j.issn.1001-4861.2013.00.136
Abstract:
Spectral terms and J-spectral multiplet of low-spin 4f95d configuration of Ho3+ were obtained with the method of ligand field theory. According to the selection rules for dipole transitions, the absorption spectra of Ho3+ doped in LiYF4 in vacuum ultraviolet region (120~160 nm) of the spectrum were theoretically interpreted by applying the crystal field model, and the four main bands were assigned to the spin-allowed transitions from the ground state (5I8) to J-spectral multiplet of low-spin 4f95d configuration of Ho3+ ion.
Spectral terms and J-spectral multiplet of low-spin 4f95d configuration of Ho3+ were obtained with the method of ligand field theory. According to the selection rules for dipole transitions, the absorption spectra of Ho3+ doped in LiYF4 in vacuum ultraviolet region (120~160 nm) of the spectrum were theoretically interpreted by applying the crystal field model, and the four main bands were assigned to the spin-allowed transitions from the ground state (5I8) to J-spectral multiplet of low-spin 4f95d configuration of Ho3+ ion.
2013, 29(4): 739-746
doi: 10.3969/j.issn.1001-4861.2013.00.098
Abstract:
A macroporous ZrO2 support was prepared by using a three-dimensional (3D) skeletal polymer through an in situ hydrolysis of Zirconium butoxide and a subsequent calcination at high temperature. Macroprocous MgO/ZrO2 composites were prepared by impregnation, calcination of magnesium nitrate solution. The composite materials were characterized by SEM, FTIR, XRD, TG-DSC. The results show that the macroporous zirconia supports have 3D ultrathin layer and the MgO nanoparticles cover on the 3D zirconia layer. The CO2-TPD curves indicate that the surface of zirconia supports has some weak alkaline sites and the sedimentation of MgO on the composite increases its alkalinity. The effect of preparation conditions on the catalytic activity was studied by using the transesterification of di-2-ethyl-hexyl carbonate from dimethyl carbonate and 2-ethyl-hexanol as the probe reaction. The results show that the macroporous MgO/ZrO2 solid base catalyst exhibits a better activity of transesterification. A better yield of the target product (65%) is obtained when the content of MgO is 50% and the calcination temperature is 600℃.
A macroporous ZrO2 support was prepared by using a three-dimensional (3D) skeletal polymer through an in situ hydrolysis of Zirconium butoxide and a subsequent calcination at high temperature. Macroprocous MgO/ZrO2 composites were prepared by impregnation, calcination of magnesium nitrate solution. The composite materials were characterized by SEM, FTIR, XRD, TG-DSC. The results show that the macroporous zirconia supports have 3D ultrathin layer and the MgO nanoparticles cover on the 3D zirconia layer. The CO2-TPD curves indicate that the surface of zirconia supports has some weak alkaline sites and the sedimentation of MgO on the composite increases its alkalinity. The effect of preparation conditions on the catalytic activity was studied by using the transesterification of di-2-ethyl-hexyl carbonate from dimethyl carbonate and 2-ethyl-hexanol as the probe reaction. The results show that the macroporous MgO/ZrO2 solid base catalyst exhibits a better activity of transesterification. A better yield of the target product (65%) is obtained when the content of MgO is 50% and the calcination temperature is 600℃.
2013, 29(4): 747-752
doi: 10.3969/j.issn.1001-4861.2013.00.047
Abstract:
The Mo-Ti composite oxide catalyst was prepared by sol-gel method and used for the transesterification of dimethyl carbonate (DMC) and phenyl acetate (PA) to diphenyl carbonate (DPC). The effect of the molar ratio of Mo/Ti and reaction conditions on the catalytic performance was investigated. The catalyst with a Mo/Ti molar ratio of 2.5 shows the highest activity. When the reaction is carried out at 180℃, with a molar ratio of PA to DMC of 2:1, the reaction time of 4 h, a catalyst amount of 0.08 (weight ratio to PA), the conversion of DMC is 74.0%, and the selectivity of DPC and MPC is 45.5% and 51.0%, respectively. According to the surface and X-ray diffraction results, lager specific areas result in improved catalytic performance by the addition of TiO2. The Mo-Ti composite oxide is composed of α-MoO3 and highly dispersed amorphous titania and/or new crystal phase of Mo-Ti composite oxide.
The Mo-Ti composite oxide catalyst was prepared by sol-gel method and used for the transesterification of dimethyl carbonate (DMC) and phenyl acetate (PA) to diphenyl carbonate (DPC). The effect of the molar ratio of Mo/Ti and reaction conditions on the catalytic performance was investigated. The catalyst with a Mo/Ti molar ratio of 2.5 shows the highest activity. When the reaction is carried out at 180℃, with a molar ratio of PA to DMC of 2:1, the reaction time of 4 h, a catalyst amount of 0.08 (weight ratio to PA), the conversion of DMC is 74.0%, and the selectivity of DPC and MPC is 45.5% and 51.0%, respectively. According to the surface and X-ray diffraction results, lager specific areas result in improved catalytic performance by the addition of TiO2. The Mo-Ti composite oxide is composed of α-MoO3 and highly dispersed amorphous titania and/or new crystal phase of Mo-Ti composite oxide.
2013, 29(4): 753-759
doi: 10.3969/j.issn.1001-4861.2013.00.122
Abstract:
Cu0.5Ce0.5O1.5/SBA-15/cordierite monolithic catalysts with the Cu0.5Ce0.5O1.5 content from 10% to 60% and 50%CuxCe1-xO2-x/SBA-15/cordierite (x=0~1) monolithic catalysts were prepared using the cordierite as the support and the CuxCe1-xO2-x/SBA-15 as the catalytic component. The catalysts were characterized using Low Temperature Nitrogen Adsorption-Desorption, XRD, XPS and H2-TPR. The catalytic activity of the catalysts for the oxidation of CO was evaluated. The results indicate that the mesoporous structure of SBA-15 is retained in the monolithic catalysts. There are the CuO and CeO2 phases in addition to the cordierite phase. On the surface of the catalyst Cu exists as Cu2+ and Cu+ species and Ce is as Ce4+ species. The redox performance of the monolithic catalysts is related with the Cu0.5Ce0.5O1.5 content and the ratio of the Cu and Ce in the CuxCe1-xO2-x/SBA-15. 50%Cu0.5Ce0.5O1.5/SBA-15/cordierite monolithic catalyst exhibits the best catalytic activity. CO can be completely oxidized at 140℃.
Cu0.5Ce0.5O1.5/SBA-15/cordierite monolithic catalysts with the Cu0.5Ce0.5O1.5 content from 10% to 60% and 50%CuxCe1-xO2-x/SBA-15/cordierite (x=0~1) monolithic catalysts were prepared using the cordierite as the support and the CuxCe1-xO2-x/SBA-15 as the catalytic component. The catalysts were characterized using Low Temperature Nitrogen Adsorption-Desorption, XRD, XPS and H2-TPR. The catalytic activity of the catalysts for the oxidation of CO was evaluated. The results indicate that the mesoporous structure of SBA-15 is retained in the monolithic catalysts. There are the CuO and CeO2 phases in addition to the cordierite phase. On the surface of the catalyst Cu exists as Cu2+ and Cu+ species and Ce is as Ce4+ species. The redox performance of the monolithic catalysts is related with the Cu0.5Ce0.5O1.5 content and the ratio of the Cu and Ce in the CuxCe1-xO2-x/SBA-15. 50%Cu0.5Ce0.5O1.5/SBA-15/cordierite monolithic catalyst exhibits the best catalytic activity. CO can be completely oxidized at 140℃.
2013, 29(4): 760-766
doi: 10.3969/j.issn.1001-4861.2013.00.086
Abstract:
A series of NTC (Negative temperature coefficient) composite material of (LaMn1-xTixO3)0.67(NiMn2O4)0.33 was prepared by solid-state method. The calcined temperature, particle size, ceramics phase structure, morphology, R-T property and electrical stability were characterized by TG/DSC, Laser particle size analyzer, XRD, SEM, resistance-temperature measurement and aging test, respectively. The results show that in the range of 1 200~1 300℃ sintered temperature, the electrical resistivity ρ25℃ of the composite ceramics increased significantly with Ti content increased. The ρ25℃ are found to be in the range of 4.4~53 179 Ω·cm and the B25/50 values are 1 357~3 998 K. The resistance drift rate ΔR/R0 of the composite ceramics after 1 000 h aging test at 125℃ was less than 0.51%. The electrical resistivity and B value of (LaMn1-xTixO3)0.67(NiMn2O4)0.33 could be adjusted to desired values. The composite system has high stability. Therefore, the (LaMn1-xTixO3)0.67(NiMn2O4)0.33 could be used for NTC thermistor as advanced semi-conducting materials.
A series of NTC (Negative temperature coefficient) composite material of (LaMn1-xTixO3)0.67(NiMn2O4)0.33 was prepared by solid-state method. The calcined temperature, particle size, ceramics phase structure, morphology, R-T property and electrical stability were characterized by TG/DSC, Laser particle size analyzer, XRD, SEM, resistance-temperature measurement and aging test, respectively. The results show that in the range of 1 200~1 300℃ sintered temperature, the electrical resistivity ρ25℃ of the composite ceramics increased significantly with Ti content increased. The ρ25℃ are found to be in the range of 4.4~53 179 Ω·cm and the B25/50 values are 1 357~3 998 K. The resistance drift rate ΔR/R0 of the composite ceramics after 1 000 h aging test at 125℃ was less than 0.51%. The electrical resistivity and B value of (LaMn1-xTixO3)0.67(NiMn2O4)0.33 could be adjusted to desired values. The composite system has high stability. Therefore, the (LaMn1-xTixO3)0.67(NiMn2O4)0.33 could be used for NTC thermistor as advanced semi-conducting materials.
Investigation of W Doped NbSe2 and Tribology Characteristic of Its Correlated Copper Base Composites
2013, 29(4): 767-773
doi: 10.3969/j.issn.1001-4861.2013.00.101
Abstract:
In this paper, W doped NbSe2 was prepared by solid phase synthesis method. Then Nb1-xWxSe2 copper base composites were synthesized by powder metallurgy method with a series of Nb1 -xWxSe2 concentration, using Nb1-xWxSe2 as solid lubrication phase and Cu as matrix phase. Phase identification and microstructure analysis of the resultant samples were carried out by XRD, SEM and TEM. The electrical resistance, hardness, and density of the block samples was measured with resistivity detector, electronic material testing machine and drainage method, respectively. The friction and wear performance was evaluated with friction and wear testing machine. It is found that the microstructure of Nb1-xWxSe2 changes from micron hexagonal sheet to the mixed of nanometer sheet and nanobelts with increasing W doping ratio. Whereas, there is nearly no influence on the resistance. Further, the resistivity of Nb1-xWxSe2/Cu base composites gradually becomes stronger as increasing the concentration of Nb1-xWxSe2, however, the friction coefficient exhibits different values. When x=0 and the percentage of Nb1-x WxSe2 is 10%, the NbSe2/Cu base composite presents the best friction and wear properties, i.e., the friction coefficient is 0.15 and wear scar is smooth and narrow. When x=3% and the percentage of Nb1-xWxSe2 is 5%, the Nb0.97W0.03Se2/Cu base composite presents the best friction and wear properties, i.e., the friction coefficient is 0.17 and wear scar is smoother and shallow. Since both nanobelts and nanosheet are existed in Nb0.97W0.03Se2 and they are intertwined, in the composites the nanosheets play an important role in the lubrication film and the winding nanobelts, which similar to the grass and branches of bird′s nest, enhance its toughening effect. Hence, both the mechanical and tribological properties of the composites are improved.
In this paper, W doped NbSe2 was prepared by solid phase synthesis method. Then Nb1-xWxSe2 copper base composites were synthesized by powder metallurgy method with a series of Nb1 -xWxSe2 concentration, using Nb1-xWxSe2 as solid lubrication phase and Cu as matrix phase. Phase identification and microstructure analysis of the resultant samples were carried out by XRD, SEM and TEM. The electrical resistance, hardness, and density of the block samples was measured with resistivity detector, electronic material testing machine and drainage method, respectively. The friction and wear performance was evaluated with friction and wear testing machine. It is found that the microstructure of Nb1-xWxSe2 changes from micron hexagonal sheet to the mixed of nanometer sheet and nanobelts with increasing W doping ratio. Whereas, there is nearly no influence on the resistance. Further, the resistivity of Nb1-xWxSe2/Cu base composites gradually becomes stronger as increasing the concentration of Nb1-xWxSe2, however, the friction coefficient exhibits different values. When x=0 and the percentage of Nb1-x WxSe2 is 10%, the NbSe2/Cu base composite presents the best friction and wear properties, i.e., the friction coefficient is 0.15 and wear scar is smooth and narrow. When x=3% and the percentage of Nb1-xWxSe2 is 5%, the Nb0.97W0.03Se2/Cu base composite presents the best friction and wear properties, i.e., the friction coefficient is 0.17 and wear scar is smoother and shallow. Since both nanobelts and nanosheet are existed in Nb0.97W0.03Se2 and they are intertwined, in the composites the nanosheets play an important role in the lubrication film and the winding nanobelts, which similar to the grass and branches of bird′s nest, enhance its toughening effect. Hence, both the mechanical and tribological properties of the composites are improved.
2013, 29(4): 774-778
doi: 10.3969/j.issn.1001-4861.2013.00.067
Abstract:
Li1.2Mn0.534Ni0.133Co0.133O2 cathode material of lithium ion batteries was prepared by co-precipitation method, and then the cathode material was coated by AlF3. The experiment results showed that the electrochemical properties of AlF3-coated material were improved obviously. Before coating, the initial discharge capacity was 253 mAh·g-1 at 0.2C with a charge/discharge efficiency of only 88.8%. However, after coating, the initial discharge capacity was 294 mAh·g-1 at 0.2C with a charge/discharge efficiency of 96.4%. Similarly, the capacity retention was also improved through AlF3 coating. The pristine material delivered a discharge capacity of only 185 mAh·g-1 (with capacity retention of 82.2%) after 50 charge/discharge cycles at 1.0C. Meanwhile, the AlF3-coated material delivered a discharge capacity of 222 mAh·g-1 (with capacity retention of 96.5%) after 50 charge/discharge cycles at 1.0C.
Li1.2Mn0.534Ni0.133Co0.133O2 cathode material of lithium ion batteries was prepared by co-precipitation method, and then the cathode material was coated by AlF3. The experiment results showed that the electrochemical properties of AlF3-coated material were improved obviously. Before coating, the initial discharge capacity was 253 mAh·g-1 at 0.2C with a charge/discharge efficiency of only 88.8%. However, after coating, the initial discharge capacity was 294 mAh·g-1 at 0.2C with a charge/discharge efficiency of 96.4%. Similarly, the capacity retention was also improved through AlF3 coating. The pristine material delivered a discharge capacity of only 185 mAh·g-1 (with capacity retention of 82.2%) after 50 charge/discharge cycles at 1.0C. Meanwhile, the AlF3-coated material delivered a discharge capacity of 222 mAh·g-1 (with capacity retention of 96.5%) after 50 charge/discharge cycles at 1.0C.
2013, 29(4): 779-785
doi: 10.3969/j.issn.1001-4861.2013.00.113
Abstract:
A new binuclear lead complex [Pb2(S2P(OR1)2)2(μ-S2P(OR1)2)2] (R1 is p-tert-butylphenyl group) was synthesized and characterized by elemental analysis, IR, UV-Vis, TG-DSC, and single crystal X-ray diffraction analysis. The crystal structure study shows that the title complex is dinuclear structure which form an chair conformation of eight-membered ring [Pb2S4P2], and the lead atom is in a distorted ψ-pentagonal bipyramidal coordination environment Pb(S5ArE) by means of the weak π coordination from an aryl group of the bridging (R1O)2PS2-ligand to lead atom and a lone pair of stereochemically active electrons originating from the lead atom. The antibacterial activities of the raw material (R1O)2PS2NH2Et2 and complex were studied against E. Coli, B. Subtilis, and S. Aureus. The bioactivity test shows that both the raw material and complex can inhibit three kinds of bacteria, and the complex has higher antibacterial activity being compared with the raw material against E. Coli and B. Subtilis. CCDC: 870009.
A new binuclear lead complex [Pb2(S2P(OR1)2)2(μ-S2P(OR1)2)2] (R1 is p-tert-butylphenyl group) was synthesized and characterized by elemental analysis, IR, UV-Vis, TG-DSC, and single crystal X-ray diffraction analysis. The crystal structure study shows that the title complex is dinuclear structure which form an chair conformation of eight-membered ring [Pb2S4P2], and the lead atom is in a distorted ψ-pentagonal bipyramidal coordination environment Pb(S5ArE) by means of the weak π coordination from an aryl group of the bridging (R1O)2PS2-ligand to lead atom and a lone pair of stereochemically active electrons originating from the lead atom. The antibacterial activities of the raw material (R1O)2PS2NH2Et2 and complex were studied against E. Coli, B. Subtilis, and S. Aureus. The bioactivity test shows that both the raw material and complex can inhibit three kinds of bacteria, and the complex has higher antibacterial activity being compared with the raw material against E. Coli and B. Subtilis. CCDC: 870009.
2013, 29(4): 786-792
doi: 10.3969/j.issn.1001-4861.2013.00.139
Abstract:
In order to improve the initial charge/discharge efficiency and rate performance of Li[Li0.2Co0.13Ni0.13Mn0.54]O2, we used citric acid and ammonium citrate tribasic to treat the materiel Li[Li0.2Co0.13Ni0.13Mn0.54]O2, which was synthesized by carbonation co-precipitated method. After surface modification, Emission Spectrometer (ICP-AES) analysis showed that lithium is the major element of the filtrate, 16.37wt% and 13.14wt% of lithium elements dissolved out during the pretreatment stage respectively, and a small amount of transition metals desorpted in this process. The charging/discharging test revealed that the materials treated by 20% of citric acid and ammonium citrate tribasic performed higher initial efficiency (80.2% and 80.7%), After 40 cycles with 0.2C cycle, the capacity retention rate increased to 97.42% and 92.70% from 91.43%, and the capacity at 1C increased to 179.5 mAh·g-1, 181.5 mAh·g-1, respectively. The results showed that after the treatment of citric acid and ammonium citrate tribasic, material properties and the rate performance were both improved.
In order to improve the initial charge/discharge efficiency and rate performance of Li[Li0.2Co0.13Ni0.13Mn0.54]O2, we used citric acid and ammonium citrate tribasic to treat the materiel Li[Li0.2Co0.13Ni0.13Mn0.54]O2, which was synthesized by carbonation co-precipitated method. After surface modification, Emission Spectrometer (ICP-AES) analysis showed that lithium is the major element of the filtrate, 16.37wt% and 13.14wt% of lithium elements dissolved out during the pretreatment stage respectively, and a small amount of transition metals desorpted in this process. The charging/discharging test revealed that the materials treated by 20% of citric acid and ammonium citrate tribasic performed higher initial efficiency (80.2% and 80.7%), After 40 cycles with 0.2C cycle, the capacity retention rate increased to 97.42% and 92.70% from 91.43%, and the capacity at 1C increased to 179.5 mAh·g-1, 181.5 mAh·g-1, respectively. The results showed that after the treatment of citric acid and ammonium citrate tribasic, material properties and the rate performance were both improved.
2013, 29(4): 793-797
doi: 10.3969/j.issn.1001-4861.2013.00.138
Abstract:
In order to improve the barium titanate (BaTiO3) particles response to electric field in hydrous elastomers, a simple surfactant-free hydrothermal method was used to synthesize the new BaTiO3, only by regulating the reaction temperature and pH of the solution. The particle was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and contact angle (CA). The results show that the BaTiO3 crystal druse is in highly pure tetragonal phase and has a good hydrophilicity. The crystal druse possesses finer electric-field response performances when it is dispersed in the gelatin aqueous elastomers.
In order to improve the barium titanate (BaTiO3) particles response to electric field in hydrous elastomers, a simple surfactant-free hydrothermal method was used to synthesize the new BaTiO3, only by regulating the reaction temperature and pH of the solution. The particle was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and contact angle (CA). The results show that the BaTiO3 crystal druse is in highly pure tetragonal phase and has a good hydrophilicity. The crystal druse possesses finer electric-field response performances when it is dispersed in the gelatin aqueous elastomers.
2013, 29(4): 798-802
doi: 10.3969/j.issn.1001-4861.2013.00.144
Abstract:
In this paper, ceria-stabilized zirconia cubic ceramics with high hardness were fabricated by pressureless sintering processing. The microstructure, XRD, Vickers hardness and relative density of the ceramics were investigated. Effects of TiO2 content (in mole) on relative density and Vickers hardness of Zr0.8Ce0.2O2 ceramics were also studied. The results show that TiO2 can effectively inhibit excessive grain growth, eliminate residual pores and promote sintering. The highest Vickers hardness is 20.2 GPa. The maximum relative density reaches up to 99.8%.
In this paper, ceria-stabilized zirconia cubic ceramics with high hardness were fabricated by pressureless sintering processing. The microstructure, XRD, Vickers hardness and relative density of the ceramics were investigated. Effects of TiO2 content (in mole) on relative density and Vickers hardness of Zr0.8Ce0.2O2 ceramics were also studied. The results show that TiO2 can effectively inhibit excessive grain growth, eliminate residual pores and promote sintering. The highest Vickers hardness is 20.2 GPa. The maximum relative density reaches up to 99.8%.
Preparation and Characterization of Mesoporous Nickel Oxide Templated by Different Mixed Surfactants
2013, 29(4): 803-809
doi: 10.3969/j.issn.1001-4861.2013.00.052
Abstract:
Mesoporous nickel oxide was prepared by hydrothermal method using Ni(NO3)2·6H2O as the nickel source, urea as the precipitant and mixed surfactant SDS/P123, CTAB/P123, CTBA/SDS as the template, at a low consumption of total surfactant. The precursor and final products were characterized by TG-DSC, FTIR, XRD, N2 adsorption-desorption, SEM and TEM. Electrochemical performances were examined by cyclic voltammetry, constant current charge-discharge and electrical impedance spectroscopy. The results show that NiO templated by mixed surfactant SDS/P123 has the highest specific surface area, pore volume and capacitance of 209 m2·g-1, 0.407 cm3·g-1 and 265 F·g-1, respectively, when the mass ratio of mSDS:mP123=2:1.
Mesoporous nickel oxide was prepared by hydrothermal method using Ni(NO3)2·6H2O as the nickel source, urea as the precipitant and mixed surfactant SDS/P123, CTAB/P123, CTBA/SDS as the template, at a low consumption of total surfactant. The precursor and final products were characterized by TG-DSC, FTIR, XRD, N2 adsorption-desorption, SEM and TEM. Electrochemical performances were examined by cyclic voltammetry, constant current charge-discharge and electrical impedance spectroscopy. The results show that NiO templated by mixed surfactant SDS/P123 has the highest specific surface area, pore volume and capacitance of 209 m2·g-1, 0.407 cm3·g-1 and 265 F·g-1, respectively, when the mass ratio of mSDS:mP123=2:1.
2013, 29(4): 810-816
doi: 10.3969/j.issn.1001-4861.2013.00.129
Abstract:
A new carboxyl-containing silicone (CCS) was synthesized by condensation reaction of chloropropylmethylsiloxane and excess amount of terephthalic acid. The CCS cured with a bisphenol A type epoxy resin, and the kinetics of curing reaction of the CCS/epoxy resin composites was investigated by employing differential scanning calorimetry (DSC) basing on the Kissinger′s and Crane′s approaches. As a result, the apparent activation energy and reaction order of the curing reaction are 71.41 kJ·mol-1 and 0.911, respectively. The curing kinetic equation at a heating rate of 10℃·min-1 was given.
A new carboxyl-containing silicone (CCS) was synthesized by condensation reaction of chloropropylmethylsiloxane and excess amount of terephthalic acid. The CCS cured with a bisphenol A type epoxy resin, and the kinetics of curing reaction of the CCS/epoxy resin composites was investigated by employing differential scanning calorimetry (DSC) basing on the Kissinger′s and Crane′s approaches. As a result, the apparent activation energy and reaction order of the curing reaction are 71.41 kJ·mol-1 and 0.911, respectively. The curing kinetic equation at a heating rate of 10℃·min-1 was given.
2013, 29(4): 817-825
doi: 10.3969/j.issn.1001-4861.2013.00.137
Abstract:
This work studies modified exfoliated layered double hydroxides (Mg2Al-NO3-LDHs) with N-(2-aminoethyl)-3-aminopropyltriethoxysilane [(CH3CH2O)3Si(CH2)3NH(CH2)2NH2, KH-791] by covalent bonding, and its selective adsorption to Pb2+, Cu2+, and Zn2+ ions from aqueous solutions. The adsorption capacity for Pb2+, Cu2+, and Zn2+ was monitored by atomic absorption technique at different metal concentrations and temperatures. Results indicate that Pb2+ ion has larger absorption capacity on the modified exfoliated Mg2Al-NO3-LDHs (EM-LDHs) than that of Cu2+ and Zn2+ ions under the same initial concentration and temperature. Compared with Pb2+ ion, the adsorption for Cu2+ or Zn2+ ion is less when the initial concentration is 500 μg·mL-1. The influence of temperature on adsorption to Pb2+ ion by EM-LDHs is more significant than that of Cu2+ and Zn2+ ions.
This work studies modified exfoliated layered double hydroxides (Mg2Al-NO3-LDHs) with N-(2-aminoethyl)-3-aminopropyltriethoxysilane [(CH3CH2O)3Si(CH2)3NH(CH2)2NH2, KH-791] by covalent bonding, and its selective adsorption to Pb2+, Cu2+, and Zn2+ ions from aqueous solutions. The adsorption capacity for Pb2+, Cu2+, and Zn2+ was monitored by atomic absorption technique at different metal concentrations and temperatures. Results indicate that Pb2+ ion has larger absorption capacity on the modified exfoliated Mg2Al-NO3-LDHs (EM-LDHs) than that of Cu2+ and Zn2+ ions under the same initial concentration and temperature. Compared with Pb2+ ion, the adsorption for Cu2+ or Zn2+ ion is less when the initial concentration is 500 μg·mL-1. The influence of temperature on adsorption to Pb2+ ion by EM-LDHs is more significant than that of Cu2+ and Zn2+ ions.
2013, 29(4): 826-830
doi: 10.3969/j.issn.1001-4861.2013.00.109
Abstract:
A mixed-valence heptanuclear manganese complex {K[MnⅡMn6Ⅲ(teaH)3(tea)3(NCS)6]}n (1) (teaH3=triethanolamine) has been synthesized by the reaction of MnCl2 (or Mn(NO3)2) with mixed ligands of teaH3 and KSCN and structurally characterized by IR, elemental analysis, single crystal X-ray diffraction. The anion of 1 consists of a Mn7 unit and compose wheel structure, in which a central MnⅡ ion surrounded by six MnⅢ ions. The result based on direct current magnetic susceptibility showed 1 a spin ground state S=29/2. The magnetic behavior of 1 indicates a ferromagnetic interaction between the high-spin MnⅡ and MnⅢ ions. CCDC: 843079.
A mixed-valence heptanuclear manganese complex {K[MnⅡMn6Ⅲ(teaH)3(tea)3(NCS)6]}n (1) (teaH3=triethanolamine) has been synthesized by the reaction of MnCl2 (or Mn(NO3)2) with mixed ligands of teaH3 and KSCN and structurally characterized by IR, elemental analysis, single crystal X-ray diffraction. The anion of 1 consists of a Mn7 unit and compose wheel structure, in which a central MnⅡ ion surrounded by six MnⅢ ions. The result based on direct current magnetic susceptibility showed 1 a spin ground state S=29/2. The magnetic behavior of 1 indicates a ferromagnetic interaction between the high-spin MnⅡ and MnⅢ ions. CCDC: 843079.
2013, 29(4): 831-837
doi: 10.3969/j.issn.1001-4861.2013.00.116
Abstract:
By using the bis(2-benzimidazolyl)alkanes as the N-donor ligand and 1,4-benzenedicarboxylic acid as the second metal linker, a novel cobalt(Ⅱ) compound with a 1D double-zigzag chain structure, namely, [Co(BDC)(H2C3PIm)(H2O)]n (1) (H2C3PIm=2,2-(1,3-propanediyl)-bis(1H-benzimidazole), BDC=1,4-benzenedicarboxylic acid) has been synthesized under hydrothermal conditions and characterized by elemental analysis, thermal analysis, X-ray single-crystal diffraction. The crystal belongs to the orthorhombic system, space group Pca21 with a=1.488 6(5) nm, b=1.791 7(5) nm, c=1.894 3(5) nm, V=5.052(3) nm3, Dc=1.360 g·cm-3, Z=8, F(000)=2 136, Goof=0.986, R1=0.042 5, wR2=0.068 7. In compound 1, the distorted tetrahedral Co(Ⅱ) ion is bridged by the carboxylic oxygen atoms of the BDC ligand and chelated by the nitrogen atoms of the H2C3PIm ligand. Owning to the different of the distorted angles from the BDC ligand, the compound units are linked into 1D double-zigzag chain structure (mode A; mode B) via the C-H…π interactions and N-H…O, O-H…O hydrogen bonding between uncoordinated carboxylate and the nitrogen atoms of H2C2EIm as well as the free water molecules and further extended into a 3D supramolecular structure through the intermolecular hydrogen bonds between the adjacent A and the adjacent B zigzag chains. The luminescent property of compound 1 has also been studied. CCDC: 839239.
By using the bis(2-benzimidazolyl)alkanes as the N-donor ligand and 1,4-benzenedicarboxylic acid as the second metal linker, a novel cobalt(Ⅱ) compound with a 1D double-zigzag chain structure, namely, [Co(BDC)(H2C3PIm)(H2O)]n (1) (H2C3PIm=2,2-(1,3-propanediyl)-bis(1H-benzimidazole), BDC=1,4-benzenedicarboxylic acid) has been synthesized under hydrothermal conditions and characterized by elemental analysis, thermal analysis, X-ray single-crystal diffraction. The crystal belongs to the orthorhombic system, space group Pca21 with a=1.488 6(5) nm, b=1.791 7(5) nm, c=1.894 3(5) nm, V=5.052(3) nm3, Dc=1.360 g·cm-3, Z=8, F(000)=2 136, Goof=0.986, R1=0.042 5, wR2=0.068 7. In compound 1, the distorted tetrahedral Co(Ⅱ) ion is bridged by the carboxylic oxygen atoms of the BDC ligand and chelated by the nitrogen atoms of the H2C3PIm ligand. Owning to the different of the distorted angles from the BDC ligand, the compound units are linked into 1D double-zigzag chain structure (mode A; mode B) via the C-H…π interactions and N-H…O, O-H…O hydrogen bonding between uncoordinated carboxylate and the nitrogen atoms of H2C2EIm as well as the free water molecules and further extended into a 3D supramolecular structure through the intermolecular hydrogen bonds between the adjacent A and the adjacent B zigzag chains. The luminescent property of compound 1 has also been studied. CCDC: 839239.
2013, 29(4): 838-844
doi: 10.3969/j.issn.1001-4861.2013.00.117
Abstract:
Proton-conducting Ba0.9La0.1Ce0.9Nd0.1O3-α ceramic was prepared by high temperature solid-state reaction. X-ray powder diffraction pattern (XRD) shows that the material is of a single orthorhombic phase of perovskite-type BaCeO3. Ionic conduction in the material under different gas atmospheres was studied by using gas concentration cell and ac impendence spectroscopy methods in the temperature range of 500~900℃, respectively, and compared with that of Ba0.9Ca0.1Ce0.9Nd0.1O3-α. The results indicate that Ba0.9La0.1Ce0.9Nd0.1O3-α is a pure protonic conductor with the protonic transport number of 1 in wet hydrogen in the range 500~900℃. In dry air, Ba0.9La0.1Ce0.9Nd0.1O3-α is a mixed conductor of oxide ion and electronic hole. The oxide ionic transport numbers are 0.295~0.081. The oxide ionic conductivity of the material is higher than that of Ba0.9Ca0.1Ce0.9Nd0.1O3-α. In wet air, Ba0.9La0.1Ce0.9Nd0.1O3-α is a mixed conductor of proton, oxide ion and electronic hole. The protonic transport numbers are 0.151~0.009, and the oxide ionic transport numbers are 0.300~0.107. The protonic conductivity of the material is lower than that of Ba0.9Ca0.1Ce0.9Nd0.1O3-α. In hydrogen-air fuel cell, Ba0.9La0.1Ce0.9Nd0.1O3-α is a mixed conductor of proton, oxide ion and electron. The ionic transport numbers are 0.964~0.853. The ionic conductivity of the material is close to that of Ba0.9Ca0.1Ce0.9Nd0.1O3-α.
Proton-conducting Ba0.9La0.1Ce0.9Nd0.1O3-α ceramic was prepared by high temperature solid-state reaction. X-ray powder diffraction pattern (XRD) shows that the material is of a single orthorhombic phase of perovskite-type BaCeO3. Ionic conduction in the material under different gas atmospheres was studied by using gas concentration cell and ac impendence spectroscopy methods in the temperature range of 500~900℃, respectively, and compared with that of Ba0.9Ca0.1Ce0.9Nd0.1O3-α. The results indicate that Ba0.9La0.1Ce0.9Nd0.1O3-α is a pure protonic conductor with the protonic transport number of 1 in wet hydrogen in the range 500~900℃. In dry air, Ba0.9La0.1Ce0.9Nd0.1O3-α is a mixed conductor of oxide ion and electronic hole. The oxide ionic transport numbers are 0.295~0.081. The oxide ionic conductivity of the material is higher than that of Ba0.9Ca0.1Ce0.9Nd0.1O3-α. In wet air, Ba0.9La0.1Ce0.9Nd0.1O3-α is a mixed conductor of proton, oxide ion and electronic hole. The protonic transport numbers are 0.151~0.009, and the oxide ionic transport numbers are 0.300~0.107. The protonic conductivity of the material is lower than that of Ba0.9Ca0.1Ce0.9Nd0.1O3-α. In hydrogen-air fuel cell, Ba0.9La0.1Ce0.9Nd0.1O3-α is a mixed conductor of proton, oxide ion and electron. The ionic transport numbers are 0.964~0.853. The ionic conductivity of the material is close to that of Ba0.9Ca0.1Ce0.9Nd0.1O3-α.
2013, 29(4): 845-849
doi: 10.3969/j.issn.1001-4861.2013.00.121
Abstract:
Two new complexes, [CuL21Cl2]DMF (1) and [CuL22Cl2] (2) (L1=N-(4-chlorophenyl)-2-(quinolin-8-yloxy)acetamide, L2=N,N-diphenyl-2-(quinolin-8-yloxy)acetamide), were synthesized and characterized by X-ray diffraction. In each complex, the six-coordinated Cu(Ⅱ) ion is in a distored octahedral geometry with the donor centers of two O atoms and two N atoms from two ligands, and two chloride anions. In the crystal of 1, intramolecular N-H…Cl hydrogen bonds link the molecules into centrosymmetric dimers. However, there are no classic hydrogen bonds in the structure of 2. CCDC: 899968, 1; 854374, 2.
Two new complexes, [CuL21Cl2]DMF (1) and [CuL22Cl2] (2) (L1=N-(4-chlorophenyl)-2-(quinolin-8-yloxy)acetamide, L2=N,N-diphenyl-2-(quinolin-8-yloxy)acetamide), were synthesized and characterized by X-ray diffraction. In each complex, the six-coordinated Cu(Ⅱ) ion is in a distored octahedral geometry with the donor centers of two O atoms and two N atoms from two ligands, and two chloride anions. In the crystal of 1, intramolecular N-H…Cl hydrogen bonds link the molecules into centrosymmetric dimers. However, there are no classic hydrogen bonds in the structure of 2. CCDC: 899968, 1; 854374, 2.
2013, 29(4): 850-854
doi: 10.3969/j.issn.1001-4861.2013.00.111
Abstract:
A new dinuclear azido-bridged copper(Ⅱ) complex [Cu2L2( μ1,3-N3)2] bearing crystallographic two-fold rotation axis symmetry has been synthesized from the tridentate Schiff base ligand 5-(ethylmethylamino)-2-[(2-morpholin-4-ylethylimino)methyl]phenol (HL) and sodium azide with copper(Ⅱ) acetate in methanol. The complex was characterized by elemental analyses, infrared spectroscopy, and X-ray single crystal determination. Crystal of the complex is crystallize as orthorhombic space group P21212, with a=0.974 6(1), b=1.378 4(2), c=1.504 1(2) nm, V=2.023 3(5) nm3, Z=2, R1=0.063 8, wR2=0.166 8. Thermal stability and magnetic property of the complex were studied. CCDC: 890948.
A new dinuclear azido-bridged copper(Ⅱ) complex [Cu2L2( μ1,3-N3)2] bearing crystallographic two-fold rotation axis symmetry has been synthesized from the tridentate Schiff base ligand 5-(ethylmethylamino)-2-[(2-morpholin-4-ylethylimino)methyl]phenol (HL) and sodium azide with copper(Ⅱ) acetate in methanol. The complex was characterized by elemental analyses, infrared spectroscopy, and X-ray single crystal determination. Crystal of the complex is crystallize as orthorhombic space group P21212, with a=0.974 6(1), b=1.378 4(2), c=1.504 1(2) nm, V=2.023 3(5) nm3, Z=2, R1=0.063 8, wR2=0.166 8. Thermal stability and magnetic property of the complex were studied. CCDC: 890948.
2013, 29(4): 855-860
doi: 10.3969/j.issn.1001-4861.2013.00.059
Abstract:
CuFe2O4 olivary particle and NiFe2O4 nanowire were synthesized by a simple seed-assisted solid state method, without any templates and surfactant assistants. The crystal structures, morphologies and magnetic properties were investigated. The results indicate that the seeds can provide crystal nucleus for generating new ferrite phase. At the same time, the seeds are beneficial for improving the purity and for realizing the shape control. The CuFe2O4 olivary particle, covered with irregular hollows, is about 0.4 μm in width and 0.8 μm in length. The diameter of the NiFe2O4 nanowire is about 10 nm, and the ratio of length to diameter could be up to 50:1. Both CuFe2O4 olivary particle and NiFe2O4 nanowire show typical superparamagnetic property at room temperature. However, the ferrites synthesized by traditional solid state method at the same condition as the title method show particle morphologies, low purity and ferromagnetic properties. These results suggest seed-assisted solid state method is an effective way to synthesize high purity ferrites with special shape.
CuFe2O4 olivary particle and NiFe2O4 nanowire were synthesized by a simple seed-assisted solid state method, without any templates and surfactant assistants. The crystal structures, morphologies and magnetic properties were investigated. The results indicate that the seeds can provide crystal nucleus for generating new ferrite phase. At the same time, the seeds are beneficial for improving the purity and for realizing the shape control. The CuFe2O4 olivary particle, covered with irregular hollows, is about 0.4 μm in width and 0.8 μm in length. The diameter of the NiFe2O4 nanowire is about 10 nm, and the ratio of length to diameter could be up to 50:1. Both CuFe2O4 olivary particle and NiFe2O4 nanowire show typical superparamagnetic property at room temperature. However, the ferrites synthesized by traditional solid state method at the same condition as the title method show particle morphologies, low purity and ferromagnetic properties. These results suggest seed-assisted solid state method is an effective way to synthesize high purity ferrites with special shape.
2013, 29(4): 861-866
doi: 10.3969/j.issn.1001-4861.2013.00.134
Abstract:
A coordination polymer of {[La(HPAA)3(H2O)2]·2(bipy)·H2O}n (1) (HHPAA=p-hydroxyphenylacetic acid, bipy=4,4′-bipyridine) was synthesized and characterized by elemental analysis, IR and TG-DTG. Its crystal structure was determined by single crystal X-ray diffraction method. The complex crystallizes in triclinic with space group P1, cell parameters: a=0.910 52(2) nm, b=1.284 78(3) nm, c=1.958 69(4) nm, α=78.586 0(1)°, β=76.656 0(1)°, γ=73.097 0(1)°, cell volume: V=2.111 98(8) nm3, number of molecules inside the cell: Z=2, relative molecular mass: Mr=958.73. The La(Ⅲ) cation is coordination with oxygen atoms from p-hydroxyphenylacetic acid anions and water molecules, forming a distorted two-capped square antiprism coordination geometry. The adjacent La(Ⅲ) clusters linked by carboxylic groups are connected by HPAA- to form a 1D chain, and the bipyridine is uncoordinated to La(Ⅲ) center. Moreover, the interaction of complex with DNA was also studied by ethidium bromide (EB) fluorescence spectroscopy. CCDC: 900442.
A coordination polymer of {[La(HPAA)3(H2O)2]·2(bipy)·H2O}n (1) (HHPAA=p-hydroxyphenylacetic acid, bipy=4,4′-bipyridine) was synthesized and characterized by elemental analysis, IR and TG-DTG. Its crystal structure was determined by single crystal X-ray diffraction method. The complex crystallizes in triclinic with space group P1, cell parameters: a=0.910 52(2) nm, b=1.284 78(3) nm, c=1.958 69(4) nm, α=78.586 0(1)°, β=76.656 0(1)°, γ=73.097 0(1)°, cell volume: V=2.111 98(8) nm3, number of molecules inside the cell: Z=2, relative molecular mass: Mr=958.73. The La(Ⅲ) cation is coordination with oxygen atoms from p-hydroxyphenylacetic acid anions and water molecules, forming a distorted two-capped square antiprism coordination geometry. The adjacent La(Ⅲ) clusters linked by carboxylic groups are connected by HPAA- to form a 1D chain, and the bipyridine is uncoordinated to La(Ⅲ) center. Moreover, the interaction of complex with DNA was also studied by ethidium bromide (EB) fluorescence spectroscopy. CCDC: 900442.
2013, 29(4): 867-874
doi: 10.3969/j.issn.1001-4861.2013.00.140
Abstract:
In order to explore new and efficient urease inhibitors, two new oxovanadium(Ⅴ) complexes, [VOL1(OCH3)(CH3OH)] (1) and [VOL2(μ-OCH3)]2 (2) (H2L1=N′-(5-chloro-2-hydroxybenzylidene)-3-nitrobenzohydrazide; H2L2=N′-(5-chloro-2-hydroxybenzylidene)-4-chlorobenzohydrazide), have been synthesized and characterized by physico-chemical methods and single-crystal X-ray diffraction. Compound 1 is a mononuclear complex, and compound 2 is a bis-methanolato bridged centrosymmetric dinuclear complex. The V atom in each complex adopts an octahedral coordination. Thermal stability and urease inhibitory activities of the complexes were studied. The percent inhibition at the concentration of 100 μmol·L-1 on Helicobacter pylori urease is 71.4% for 1 and 73.3% for 2. The IC50 values for 1 and 2 are 63.6 and 37.7 μmol·L-1, respectively. CCDC: 858857, 1; and 858858, 2.
In order to explore new and efficient urease inhibitors, two new oxovanadium(Ⅴ) complexes, [VOL1(OCH3)(CH3OH)] (1) and [VOL2(μ-OCH3)]2 (2) (H2L1=N′-(5-chloro-2-hydroxybenzylidene)-3-nitrobenzohydrazide; H2L2=N′-(5-chloro-2-hydroxybenzylidene)-4-chlorobenzohydrazide), have been synthesized and characterized by physico-chemical methods and single-crystal X-ray diffraction. Compound 1 is a mononuclear complex, and compound 2 is a bis-methanolato bridged centrosymmetric dinuclear complex. The V atom in each complex adopts an octahedral coordination. Thermal stability and urease inhibitory activities of the complexes were studied. The percent inhibition at the concentration of 100 μmol·L-1 on Helicobacter pylori urease is 71.4% for 1 and 73.3% for 2. The IC50 values for 1 and 2 are 63.6 and 37.7 μmol·L-1, respectively. CCDC: 858857, 1; and 858858, 2.
2013, 29(4): 875-882
doi: 10.3969/j.issn.1001-4861.2013.00.114
Abstract:
Three nickel carborane disphosphine complexes [NiCl(Py){7, 8-(PPh2)2-7,8-C2B9H10}]CH2Cl2(1), [Ni{7, 8-(PPh2)2-7, 8-C2B9H10}2](2) and [Ni{7, 8-(OPPh2)-7, 8-C2B9H10}{7, 8-(PPh2)-7, 8-C2B9H10}](3) have been synthesized and characterized by elemental analysis, FTIR, 1H and 13C NMR spectroscopy and X-ray structure determination. Single crystal analysis shows that the coordination environment of the Ni atom is a slightly distorted square-planar in the complexes 1~3, in which the four positions are occupied by two P atoms, one Cl atom and one N atom of pyridine in 1, four P atoms in 2 and two P atoms and two O atoms in 3, respectively. One dimensional chain structure can be formed depending on C-H…Cl or dihydrogen bonding interactions in these three complexes. CCDC: 749848, 1; 749846, 2; 799937, 3.
Three nickel carborane disphosphine complexes [NiCl(Py){7, 8-(PPh2)2-7,8-C2B9H10}]CH2Cl2(1), [Ni{7, 8-(PPh2)2-7, 8-C2B9H10}2](2) and [Ni{7, 8-(OPPh2)-7, 8-C2B9H10}{7, 8-(PPh2)-7, 8-C2B9H10}](3) have been synthesized and characterized by elemental analysis, FTIR, 1H and 13C NMR spectroscopy and X-ray structure determination. Single crystal analysis shows that the coordination environment of the Ni atom is a slightly distorted square-planar in the complexes 1~3, in which the four positions are occupied by two P atoms, one Cl atom and one N atom of pyridine in 1, four P atoms in 2 and two P atoms and two O atoms in 3, respectively. One dimensional chain structure can be formed depending on C-H…Cl or dihydrogen bonding interactions in these three complexes. CCDC: 749848, 1; 749846, 2; 799937, 3.
2013, 29(4): 883-888
doi: 10.3969/j.issn.1001-4861.2013.00.124
Abstract:
The self-assembly of 2,4-dichlorophenoxyacetic acid (Hdcp), 4,4′-bipyridine (bpy) and Nd(NO3)3·6H2O under hydrothermal condition gave one new 1D neodymium coordination polymer, {[Nd(dcp)3(H2O)2]·1.5bpy·2H2O}n (1) (dcp=2,4-dichlorophenoxyacetate, bpy=4,4′-bipyridine) which has been characterized by elemental analysis, IR, TGA, PXRD, UV-Vis and single-crystal X-ray diffraction. The dcp ligands linked the Nd(Ⅲ) ions to form an infinite linear chain with a {Nd2(dcp)6(H2O)4} repeat units. Neighboring chains are bridged into a layer structure through O-H…O and O-H…N hydrogen bonds involving the coordinated water molecules, free water molecules and free bpy ligands. The photoluminescence and lifetime of complex 1 in the solid state at room temperature have been studied. CCDC: 894242.
The self-assembly of 2,4-dichlorophenoxyacetic acid (Hdcp), 4,4′-bipyridine (bpy) and Nd(NO3)3·6H2O under hydrothermal condition gave one new 1D neodymium coordination polymer, {[Nd(dcp)3(H2O)2]·1.5bpy·2H2O}n (1) (dcp=2,4-dichlorophenoxyacetate, bpy=4,4′-bipyridine) which has been characterized by elemental analysis, IR, TGA, PXRD, UV-Vis and single-crystal X-ray diffraction. The dcp ligands linked the Nd(Ⅲ) ions to form an infinite linear chain with a {Nd2(dcp)6(H2O)4} repeat units. Neighboring chains are bridged into a layer structure through O-H…O and O-H…N hydrogen bonds involving the coordinated water molecules, free water molecules and free bpy ligands. The photoluminescence and lifetime of complex 1 in the solid state at room temperature have been studied. CCDC: 894242.
