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2020 Volume 39 Issue 2
2020, 39(2): 189-199
doi: 10.14102/j.cnki.0254–5861.2011–2748
Abstract:
The interaction of water (H2O) with metal oxide surfaces is of fundamental importance to various fields of science, ranging from batteries to catalysis. In particular, vanadium pentoxide (V2O5) has been widely used as electrode materials for aqueous-battery and catalysts. Herein, theoretical (density functional theory) study gives atomic-scale insights into water monolayers in V2O5 and single-molecule adsorption and dissociation at three low-index surfaces and oxygen-vacancy V2O5(001) surface. The H2O/V2O5 interface structure was identified. The results show that H2O is adsorbed on the stoichiometric V2O5(001) surface with physisorption mechanism, and the dissociation hardly occurs. Water adsorbs as an intact monomer with a computed binding energy of 0.75 eV. The formation of ordered water overlayers has been observed on V2O5(001) surface, suggesting a locally ordered superstructure of molecular water. The molecular H2O adsorption on oxygen-vacancy V2O5(001) surface is stronger than that on the stoichiometric V2O5(001) surface, and H2O can undergo dissociative chemisorption to form a surface hydroxyl group and a H adatom. V2O5 can take the oxygen from H2O, which is consistent with the experimental results.
The interaction of water (H2O) with metal oxide surfaces is of fundamental importance to various fields of science, ranging from batteries to catalysis. In particular, vanadium pentoxide (V2O5) has been widely used as electrode materials for aqueous-battery and catalysts. Herein, theoretical (density functional theory) study gives atomic-scale insights into water monolayers in V2O5 and single-molecule adsorption and dissociation at three low-index surfaces and oxygen-vacancy V2O5(001) surface. The H2O/V2O5 interface structure was identified. The results show that H2O is adsorbed on the stoichiometric V2O5(001) surface with physisorption mechanism, and the dissociation hardly occurs. Water adsorbs as an intact monomer with a computed binding energy of 0.75 eV. The formation of ordered water overlayers has been observed on V2O5(001) surface, suggesting a locally ordered superstructure of molecular water. The molecular H2O adsorption on oxygen-vacancy V2O5(001) surface is stronger than that on the stoichiometric V2O5(001) surface, and H2O can undergo dissociative chemisorption to form a surface hydroxyl group and a H adatom. V2O5 can take the oxygen from H2O, which is consistent with the experimental results.
2020, 39(2): 200-205
doi: 10.14102/j.cnki.0254–5861.2011–2749
Abstract:
Interfacial reaction is a critical factor of lithium ion battery, but is also complicated and difficult to characterize. Scanning probe microscope (SPM) is one of the most effective tools to reveal the interface reconstruction and interfacial properties (including the morphologies, mechanical properties and electricity properties) of energy material at nanoscale and at real time. In this paper, we briefly summarized the principles of AFM, conductive AFM(C-AFM) and Kelvin probe force microscope (KPFM), as well as their application to investigate the interface reconstruction of lithium-ion battery electrode material.
Interfacial reaction is a critical factor of lithium ion battery, but is also complicated and difficult to characterize. Scanning probe microscope (SPM) is one of the most effective tools to reveal the interface reconstruction and interfacial properties (including the morphologies, mechanical properties and electricity properties) of energy material at nanoscale and at real time. In this paper, we briefly summarized the principles of AFM, conductive AFM(C-AFM) and Kelvin probe force microscope (KPFM), as well as their application to investigate the interface reconstruction of lithium-ion battery electrode material.
2020, 39(2): 206-213
doi: 10.14102/j.cnki.0254–5861.2011–2011-2756
Abstract:
Electrochemical CO2 reduction reaction (CO2RR) has been considered as a feasible avenue for simultaneous conversion of renewable energy and CO2. Economic and technical analysis suggests that the production of valuable C1 chemicals such as formic acid and CO is the most economically practicable route for CO2RR. This perspective summarizes the performance of electrodeposited Sn-based catalysts for C1 chemicals production and the relative mechanism of CO2RR. Further fundamental understanding and industrial applications of electrodeposited Sn-based catalysts in CO2 electrolyzer device are also discussed.
Electrochemical CO2 reduction reaction (CO2RR) has been considered as a feasible avenue for simultaneous conversion of renewable energy and CO2. Economic and technical analysis suggests that the production of valuable C1 chemicals such as formic acid and CO is the most economically practicable route for CO2RR. This perspective summarizes the performance of electrodeposited Sn-based catalysts for C1 chemicals production and the relative mechanism of CO2RR. Further fundamental understanding and industrial applications of electrodeposited Sn-based catalysts in CO2 electrolyzer device are also discussed.
2020, 39(2): 214-228
doi: 10.14102/j.cnki.0254–5861.2011–2416
Abstract:
Theoretical calculations of Double Hanging Ring Molecule (DHRM) [(GnHn–1m)(GnHn–1m)] (G = C, Si, Ge; n = 3, 5, 6, 7, 8; m = +1, –1, 0, +1, +2) were performed via Gaussian 09 with the method of Density Functional Theory (DFT). Geometrical optimization, Potential Energy surface Scan (PES), Degree of Aromaticity (DOA) and Nucleus Independent Chemical Shift (NICS) were computed to study the optimal structures and aromaticity of DHRMs. Ring Stretching Vibration Raman Spectroscopy (RSVRSF) was predicted to seek the relation between RSVRSF and aromaticity of DHRMs. The results show optimal structures of DHRMs[(GnHn–1m)(GnHn–1m)] (n = 3, 5~8); DA = 90° is the stable structure when n = 3, 7, 8; while n = 5 corresponds to DA = 30°, n = 6 corresponds to DA = 50°; the correlation between DOA and NICS of DHRMs is quadratic; the value of RSVRSF of DHRM approximates to its corresponding single ring molecule, which could act as characteristic frequency of ring molecule to identify its aromaticity; the correlation between RSVRSF and DOA is quadratic, and that between RSVRSF and NICS is linear.
Theoretical calculations of Double Hanging Ring Molecule (DHRM) [(GnHn–1m)(GnHn–1m)] (G = C, Si, Ge; n = 3, 5, 6, 7, 8; m = +1, –1, 0, +1, +2) were performed via Gaussian 09 with the method of Density Functional Theory (DFT). Geometrical optimization, Potential Energy surface Scan (PES), Degree of Aromaticity (DOA) and Nucleus Independent Chemical Shift (NICS) were computed to study the optimal structures and aromaticity of DHRMs. Ring Stretching Vibration Raman Spectroscopy (RSVRSF) was predicted to seek the relation between RSVRSF and aromaticity of DHRMs. The results show optimal structures of DHRMs[(GnHn–1m)(GnHn–1m)] (n = 3, 5~8); DA = 90° is the stable structure when n = 3, 7, 8; while n = 5 corresponds to DA = 30°, n = 6 corresponds to DA = 50°; the correlation between DOA and NICS of DHRMs is quadratic; the value of RSVRSF of DHRM approximates to its corresponding single ring molecule, which could act as characteristic frequency of ring molecule to identify its aromaticity; the correlation between RSVRSF and DOA is quadratic, and that between RSVRSF and NICS is linear.
2020, 39(2): 229-242
doi: 10.14102/j.cnki.0254–5861.2011–2439
Abstract:
Humic acid is an important active component in soil environment. The spatial structures of P complexation sites in humic acid complexes play an important role in soil phosphorus activation and fertilizer efficiency. To explore the effects of spatial structure, the three different coordination modes of iron-carboxyl in models were calculated by the ONIOM method available in the Gaussian09 package. The (U)B3LYP hybrid density functional was employed to optimize the configuration for the QM region, and the UFF force field was used to calculate for the MM region. The results show that the different spatial structures influence the soil phosphorus activation by affecting the electronic structure, Gibbs free energy and interaction energy of the models. And the effects are as follows: the unidentate structure model 6P-Fe-MHA-UD, the bidentate chelating structure model 6P-Fe-MHA-BD > the bidentate bridging structure model 5P-Fe-MHA-BD-BG. It can be known that, the fertilizer efficiency can be improved through increasing the proportion of the unidentate structure and the bidentate chelating structure in production engineering. The research provides a theoretical basis for further optimization of the production of humic acid phosphate fertilizer.
Humic acid is an important active component in soil environment. The spatial structures of P complexation sites in humic acid complexes play an important role in soil phosphorus activation and fertilizer efficiency. To explore the effects of spatial structure, the three different coordination modes of iron-carboxyl in models were calculated by the ONIOM method available in the Gaussian09 package. The (U)B3LYP hybrid density functional was employed to optimize the configuration for the QM region, and the UFF force field was used to calculate for the MM region. The results show that the different spatial structures influence the soil phosphorus activation by affecting the electronic structure, Gibbs free energy and interaction energy of the models. And the effects are as follows: the unidentate structure model 6P-Fe-MHA-UD, the bidentate chelating structure model 6P-Fe-MHA-BD > the bidentate bridging structure model 5P-Fe-MHA-BD-BG. It can be known that, the fertilizer efficiency can be improved through increasing the proportion of the unidentate structure and the bidentate chelating structure in production engineering. The research provides a theoretical basis for further optimization of the production of humic acid phosphate fertilizer.
2020, 39(2): 243-254
doi: 10.14102/j.cnki.0254–5861.2011–2448
Abstract:
The performance of organic fluorescent materials can be improved by chemical substitutions with auxochrome groups such as amino to increase solubility, alter emitting color, or modify film quality. The complex 6, 6-difluoro-6-bora-5-oxa-11-thia-6a-aza-benzo[a]fluorine (BOBTP) and its derivatives, which possess excellent luminescent property at room temperature, were theoretically simulated by density functional theory. The geometries of the ground state and the first excited state of BOBTPs complexes were investigated and their bond parameters were obtained. Further, these bond parameters are compared with each other, and the computational wavelengths of maximum absorption and emission of studied complexes match up with the experimental values. It was found that amino substituent bonding to appropriate positions of BOBTP can reduce the reorganization energy significantly, which is ascribed to electron-donating effect of the amino group. The reorganization energy also plays an important role in the fluorescence quantum yield of all the BOBTPs. In particular, the radiative decay of complexes 3 and 4 is dominant due to the smaller reorganization energies, so their fluorescence quantum yield is almost 1, on the contrary the non-radiative decay and intersystem crossing rate of both the 1 and 2 can not be ignored for the larger reorganization energies, and the corresponding fluorescence quantum yields were calculated when the radiative decay rate (kr) and nonradiative decay rate (knr) were taken into account.
The performance of organic fluorescent materials can be improved by chemical substitutions with auxochrome groups such as amino to increase solubility, alter emitting color, or modify film quality. The complex 6, 6-difluoro-6-bora-5-oxa-11-thia-6a-aza-benzo[a]fluorine (BOBTP) and its derivatives, which possess excellent luminescent property at room temperature, were theoretically simulated by density functional theory. The geometries of the ground state and the first excited state of BOBTPs complexes were investigated and their bond parameters were obtained. Further, these bond parameters are compared with each other, and the computational wavelengths of maximum absorption and emission of studied complexes match up with the experimental values. It was found that amino substituent bonding to appropriate positions of BOBTP can reduce the reorganization energy significantly, which is ascribed to electron-donating effect of the amino group. The reorganization energy also plays an important role in the fluorescence quantum yield of all the BOBTPs. In particular, the radiative decay of complexes 3 and 4 is dominant due to the smaller reorganization energies, so their fluorescence quantum yield is almost 1, on the contrary the non-radiative decay and intersystem crossing rate of both the 1 and 2 can not be ignored for the larger reorganization energies, and the corresponding fluorescence quantum yields were calculated when the radiative decay rate (kr) and nonradiative decay rate (knr) were taken into account.
2020, 39(2): 255-262
doi: 10.14102/j.cnki.0254–5861.2011–2453
Abstract:
In this study, density functional theory calculations reveal how boron group ions M+ (M = B, Al, Ga, In, and Tl) directly convert carbon and methane into ethylene at room temperature. M+ reacts with the carbon atom to form the cation MC+. Then, the reaction of MC+ with methane leads to the cleavage of metal–carbon bond and the formation of CH2CH2 through C–C coupling, with the ion M+ serving as a leaving group. The cycle then begins again. The mechanism of C/CH4 system catalyzed by five ion types is investigated herein, and the reasons for the different reactivity of five ion types are determined. The moderate strength of the Al+–C bond results in Al+ being the only appropriate catalyst of M+ (M = B, Al, Ga, In, and Tl) that can catalyze methane and carbon into ethylene.
In this study, density functional theory calculations reveal how boron group ions M+ (M = B, Al, Ga, In, and Tl) directly convert carbon and methane into ethylene at room temperature. M+ reacts with the carbon atom to form the cation MC+. Then, the reaction of MC+ with methane leads to the cleavage of metal–carbon bond and the formation of CH2CH2 through C–C coupling, with the ion M+ serving as a leaving group. The cycle then begins again. The mechanism of C/CH4 system catalyzed by five ion types is investigated herein, and the reasons for the different reactivity of five ion types are determined. The moderate strength of the Al+–C bond results in Al+ being the only appropriate catalyst of M+ (M = B, Al, Ga, In, and Tl) that can catalyze methane and carbon into ethylene.
2020, 39(2): 263-268
doi: 10.14102/j.cnki.0254–5861.2011–2458
Abstract:
Organic molecules are attractive electrode materials for rechargeable batteries owing to their sustainability, low cost, and light weight. In this work, we report a new organic anode, a perimidin derivative 1, 3, 5-tri(1H-perimidin-2-yl)-benzene (TPB), for lithium-ion batteries. The TPB structure contains multiple redox centers including π-conjugated benzene ring, C=N, and -NH groups and delivers a high reversible specific capacity of 300 mAh/g at 50 mA/g under a six-electron redox reaction. Moreover, TPB exhibits excellent rate capability and long-term cyclability with 98.1% capacity retention over 1500 cycles at 1000 mA/g. The results may open new opportunities for the development of low-cost and long-lifespan lithium-ion batteries.
Organic molecules are attractive electrode materials for rechargeable batteries owing to their sustainability, low cost, and light weight. In this work, we report a new organic anode, a perimidin derivative 1, 3, 5-tri(1H-perimidin-2-yl)-benzene (TPB), for lithium-ion batteries. The TPB structure contains multiple redox centers including π-conjugated benzene ring, C=N, and -NH groups and delivers a high reversible specific capacity of 300 mAh/g at 50 mA/g under a six-electron redox reaction. Moreover, TPB exhibits excellent rate capability and long-term cyclability with 98.1% capacity retention over 1500 cycles at 1000 mA/g. The results may open new opportunities for the development of low-cost and long-lifespan lithium-ion batteries.
2020, 39(2): 269-278
doi: 10.14102/j.cnki.0254–5861.2011–2467
Abstract:
6-Hydroxybentazon, a metabolite of bentazon, was synthesized and characterized herein. The structure of the title compound 11 was verified by single-crystal X-ray crystallography. The optimized crystal structure as well as the HOMO and LUMO levels of the title compound was determined by density functional theory calculations at the B3LYP/6-311G(d, p) level.
6-Hydroxybentazon, a metabolite of bentazon, was synthesized and characterized herein. The structure of the title compound 11 was verified by single-crystal X-ray crystallography. The optimized crystal structure as well as the HOMO and LUMO levels of the title compound was determined by density functional theory calculations at the B3LYP/6-311G(d, p) level.
2020, 39(2): 279-286
doi: 10.14102/j.cnki.0254–5861.2011–2420
Abstract:
Single crystals of two Schiff base compounds 1 and 2 derived from 1-amino-2-hydroxypropane were obtained via condensation reaction of an amine and a reactive carbonyl group. The compounds were characterized by elemental analysis, IR and single-crystal X-ray diffraction. Compound 1 (C10H13NO2) crystallizes in the monoclinic system, space group P21 with a = 4.487(9), b = 10.913(2), c = 9.886(19) Å, β = 97.823(3)º, V = 479.59(16) Å3, Z = 2, Mr = 179.21, Dc = 1.241 g/cm3, F(000) = 192, GOOF = 1.005, μ = 0.087 mm-1, the final R = 0.0328 and wR = 0.0738 for 1721 observed reflections with I > 2σ(I). Compound 2 (C14H20N2O2) crystallizes in orthorhombic system, space group Pbca with a = 6.295(2), b = 7.290(3), c = 30.519(11) Å, V = 1400.5(9) Å3, Z = 8, Mr = 248.32, Dc = 1.178 g/cm3, F(000) = 536, GOOF = 1.125, μ = 0.079 mm-1, the final R = 0.0871 and wR = 0.1748 for 1307 observed reflections with I > 2σ(I). Compound 1 exhibits a 3D supramolecular structure and compound 2 show a 3D supramolecular structure under hydrogen bonding interactions. Furthermore, the infrared stealthy performance of two Schiff base compounds and their Fe(Ⅲ) complexes were studied. The results show that their Fe(Ⅲ) complexes show lower infrared emissivity than corresponding Schiff base compounds, and the lowest infrared emissivity reaches to 0.657.
Single crystals of two Schiff base compounds 1 and 2 derived from 1-amino-2-hydroxypropane were obtained via condensation reaction of an amine and a reactive carbonyl group. The compounds were characterized by elemental analysis, IR and single-crystal X-ray diffraction. Compound 1 (C10H13NO2) crystallizes in the monoclinic system, space group P21 with a = 4.487(9), b = 10.913(2), c = 9.886(19) Å, β = 97.823(3)º, V = 479.59(16) Å3, Z = 2, Mr = 179.21, Dc = 1.241 g/cm3, F(000) = 192, GOOF = 1.005, μ = 0.087 mm-1, the final R = 0.0328 and wR = 0.0738 for 1721 observed reflections with I > 2σ(I). Compound 2 (C14H20N2O2) crystallizes in orthorhombic system, space group Pbca with a = 6.295(2), b = 7.290(3), c = 30.519(11) Å, V = 1400.5(9) Å3, Z = 8, Mr = 248.32, Dc = 1.178 g/cm3, F(000) = 536, GOOF = 1.125, μ = 0.079 mm-1, the final R = 0.0871 and wR = 0.1748 for 1307 observed reflections with I > 2σ(I). Compound 1 exhibits a 3D supramolecular structure and compound 2 show a 3D supramolecular structure under hydrogen bonding interactions. Furthermore, the infrared stealthy performance of two Schiff base compounds and their Fe(Ⅲ) complexes were studied. The results show that their Fe(Ⅲ) complexes show lower infrared emissivity than corresponding Schiff base compounds, and the lowest infrared emissivity reaches to 0.657.
2020, 39(2): 287-293
doi: 10.14102/j.cnki.0254–5861.2011–2446
Abstract:
A kind of nitrogen-doped carbon (NC) nanomaterials was prepared via calcining the nitrogen-rich organic molecular glycoluril under nitrogen atmosphere. Elemental analysis result indicates the N content of the obtained NC is 13.9 wt.%. Electrochemical measurement demonstrated that the obtained NC catalyst is an efficient ORR electrocatalyst in alkaline electrolyte. The process of ORR is dominated by a four-electron transfer pathway with the most efficient catalytic activity. In addition, the NC catalyst exhibits excellent stability and good resistance to methanol poisoning. After 10000 s of chronoamperometric durability test, the relative current of NC catalyst retained as high as 95%. This work provides a new strategy for the preparation of cost-effective ORR catalysts with high catalytic performance.
A kind of nitrogen-doped carbon (NC) nanomaterials was prepared via calcining the nitrogen-rich organic molecular glycoluril under nitrogen atmosphere. Elemental analysis result indicates the N content of the obtained NC is 13.9 wt.%. Electrochemical measurement demonstrated that the obtained NC catalyst is an efficient ORR electrocatalyst in alkaline electrolyte. The process of ORR is dominated by a four-electron transfer pathway with the most efficient catalytic activity. In addition, the NC catalyst exhibits excellent stability and good resistance to methanol poisoning. After 10000 s of chronoamperometric durability test, the relative current of NC catalyst retained as high as 95%. This work provides a new strategy for the preparation of cost-effective ORR catalysts with high catalytic performance.
2020, 39(2): 294-300
doi: 10.14102/j.cnki.0254–5861.2011–2418
Abstract:
The 2, 2΄-((sulfonylbis(4, 1-phenylene))bis(oxy))diacetic acid (H2L) and 4, 4΄-bipy-ridine (4, 4΄-bipy) are employed as organic ligands to react with metal salts to obtain two new metal-organic frameworks (MOFs), namely [M2L2(4, 4΄-bipy)] (M = Zn(1), Cu(2)). They have been successfully synthesized under hydrothermal conditions. Single-crystal X-ray diffraction reveals that two complexes are isostructural and crystallize in orthorhombic system with space group Pbcn. All L2- ligands bridge metal ions to form an infinite 1D Z-shaped chain along the a axis. Then through 4, 4΄-bipy, contiguous Z-shaped chains are linked to form a 2D layer structure. The luminescent studies of the H2L ligand and complex 1 in the solid state and thermogravimetric analyses (TGA) of two complexes are investigated.
The 2, 2΄-((sulfonylbis(4, 1-phenylene))bis(oxy))diacetic acid (H2L) and 4, 4΄-bipy-ridine (4, 4΄-bipy) are employed as organic ligands to react with metal salts to obtain two new metal-organic frameworks (MOFs), namely [M2L2(4, 4΄-bipy)] (M = Zn(1), Cu(2)). They have been successfully synthesized under hydrothermal conditions. Single-crystal X-ray diffraction reveals that two complexes are isostructural and crystallize in orthorhombic system with space group Pbcn. All L2- ligands bridge metal ions to form an infinite 1D Z-shaped chain along the a axis. Then through 4, 4΄-bipy, contiguous Z-shaped chains are linked to form a 2D layer structure. The luminescent studies of the H2L ligand and complex 1 in the solid state and thermogravimetric analyses (TGA) of two complexes are investigated.
2020, 39(2): 301-309
doi: 10.14102/j.cnki.0254–5861.2011–2422
Abstract:
In this work, novel phosphors Na5Gd(WO4)4: Tb3+/Yb3+ and Na5Gd(WO4)4: Tb3+/Er3+/Yb3+ phosphors were synthesized by the solid state reaction method. The photoluminescence properties were investigated. The introduction of Er3+ to NGW: Tb3+/Yb3+ was used to modify the chromaticity coordinates, then providing a good color tunable property. The change in the chromaticity coordinates induces the shift of emission color from yellow-green to blue-green for NGW: Tb3+/Er3+/Yb3+ as the temperature increases. All the results indicate that the NGW: Er3+/Tb3+/Yb3+ phosphors may be used as optical temperature sensing materials.
In this work, novel phosphors Na5Gd(WO4)4: Tb3+/Yb3+ and Na5Gd(WO4)4: Tb3+/Er3+/Yb3+ phosphors were synthesized by the solid state reaction method. The photoluminescence properties were investigated. The introduction of Er3+ to NGW: Tb3+/Yb3+ was used to modify the chromaticity coordinates, then providing a good color tunable property. The change in the chromaticity coordinates induces the shift of emission color from yellow-green to blue-green for NGW: Tb3+/Er3+/Yb3+ as the temperature increases. All the results indicate that the NGW: Er3+/Tb3+/Yb3+ phosphors may be used as optical temperature sensing materials.
2020, 39(2): 310-320
doi: 10.14102/j.cnki.0254–5861.2011–2405
Abstract:
Single crystal of lithium terbium tungstate LiTb(WO4)2 has been grown by the flux method. The crystal structure was refined from single-crystal X-ray data. It crystallizes in tetragonal system, space group I41/a with a = 5.1749(9), c = 11.1953(19) Å, V = 299.81(12) Å3, Z = 2, Mr = 661.56, Dc = 7.328 g/cm3, F(000) = 560, μ(MoKα) = 49.94 mm-1, R(F2 > 2σ(F2)) = 0.026 and wR(F2) = 0.070. It features a typical scheelite-type structure composed of two-direction packing of isolated WO4 tetrahedra. Li and Tb atoms in the structure occupy the same crystallographic site. Moreover, a series of solid solution phosphors LiTb1-xEux(WO4)2 (x = 0.004~0.1) were synthesized by high temperature solid-state reactions. The phosphors could be effectively excited by a wavelength range from 379 to 487 nm, which matches well with the UV and near-UV LED chip. The emission color of the phosphor can be tuned from green, through yellow to red by simply adjusting the relative Eu3+ and Tb3+ concentration due to the Tb3+ to Eu3+ energy transfer.
Single crystal of lithium terbium tungstate LiTb(WO4)2 has been grown by the flux method. The crystal structure was refined from single-crystal X-ray data. It crystallizes in tetragonal system, space group I41/a with a = 5.1749(9), c = 11.1953(19) Å, V = 299.81(12) Å3, Z = 2, Mr = 661.56, Dc = 7.328 g/cm3, F(000) = 560, μ(MoKα) = 49.94 mm-1, R(F2 > 2σ(F2)) = 0.026 and wR(F2) = 0.070. It features a typical scheelite-type structure composed of two-direction packing of isolated WO4 tetrahedra. Li and Tb atoms in the structure occupy the same crystallographic site. Moreover, a series of solid solution phosphors LiTb1-xEux(WO4)2 (x = 0.004~0.1) were synthesized by high temperature solid-state reactions. The phosphors could be effectively excited by a wavelength range from 379 to 487 nm, which matches well with the UV and near-UV LED chip. The emission color of the phosphor can be tuned from green, through yellow to red by simply adjusting the relative Eu3+ and Tb3+ concentration due to the Tb3+ to Eu3+ energy transfer.
2020, 39(2): 321-328
doi: 10.14102/j.cnki.0254–5861.2011–2339
Abstract:
A new Cu(Ⅱ) coordination polymer, {[Cu(1, 3-BIP)(TFBDC)]·DMF}n (1, 1, 3-BIP is a 1, 3-bis(imidazole)propane, and H2TFBDC is 2, 3, 5, 6-tetrafluoroterephthalic acid) was prepared under solvothermal conditions and characterized by single-crystal and powder X-ray diffraction, IR spectra, thermogravimetric analyses and elemental analyses. The single-crystal X-ray diffraction reveals that metal coordination polymer 1 (MCP 1) shows a two-dimensional sheet layer structure, which is further reinforced through strong intermolecular hydrogen bonding to form a 3D supramolecular framework. Furthermore, the photocatalytic experiment result indicates the degradation ratios of methyl orange (MO) reach 83.4% within 180 minutes when MCP 1 acts as catalyst.
A new Cu(Ⅱ) coordination polymer, {[Cu(1, 3-BIP)(TFBDC)]·DMF}n (1, 1, 3-BIP is a 1, 3-bis(imidazole)propane, and H2TFBDC is 2, 3, 5, 6-tetrafluoroterephthalic acid) was prepared under solvothermal conditions and characterized by single-crystal and powder X-ray diffraction, IR spectra, thermogravimetric analyses and elemental analyses. The single-crystal X-ray diffraction reveals that metal coordination polymer 1 (MCP 1) shows a two-dimensional sheet layer structure, which is further reinforced through strong intermolecular hydrogen bonding to form a 3D supramolecular framework. Furthermore, the photocatalytic experiment result indicates the degradation ratios of methyl orange (MO) reach 83.4% within 180 minutes when MCP 1 acts as catalyst.
2020, 39(2): 329-339
doi: 10.14102/j.cnki.0254–5861.2011–2394
Abstract:
A new mixed metal phosphate of Cs2Ga4P8O27, which also can be written as Cs2Ga4(P2O7)2(P4O13), was synthesized by high temperature solid state syntheses and structurally characterized by X-ray single-crystal diffraction for the first time. The title compound crystallizes in monoclinic system with space group P21/c (No. 14), and features a 3D framework which can be considered as alternating layers of {Ga2(P4O13)}n and {Ga2(P2O7)2}n2n- parallel to the bc plane further connected by Ga−O−P linkages, where Cs+ cations are located in the free space between two adjacent layers to charge the valence. The Ga3+ cations in the compound contain two kinds of coordination models (4 and 6). Furthermore, the title compound coexists of two phospho-ric anionic groups which are non-condensed horseshoe-shaped (P4O13) and two (P2O7) with different symmetries. The density functional theory calculations indicate that Cs2Ga4P8O27 is a direct band gap insulator with flat valence and dispersive conduction bands and a band gap of 4.13 eV.
A new mixed metal phosphate of Cs2Ga4P8O27, which also can be written as Cs2Ga4(P2O7)2(P4O13), was synthesized by high temperature solid state syntheses and structurally characterized by X-ray single-crystal diffraction for the first time. The title compound crystallizes in monoclinic system with space group P21/c (No. 14), and features a 3D framework which can be considered as alternating layers of {Ga2(P4O13)}n and {Ga2(P2O7)2}n2n- parallel to the bc plane further connected by Ga−O−P linkages, where Cs+ cations are located in the free space between two adjacent layers to charge the valence. The Ga3+ cations in the compound contain two kinds of coordination models (4 and 6). Furthermore, the title compound coexists of two phospho-ric anionic groups which are non-condensed horseshoe-shaped (P4O13) and two (P2O7) with different symmetries. The density functional theory calculations indicate that Cs2Ga4P8O27 is a direct band gap insulator with flat valence and dispersive conduction bands and a band gap of 4.13 eV.
2020, 39(2): 350-355
doi: 10.14102/j.cnki.0254–5861.2011–2481
Abstract:
A new binuclear cage-like samarium(Ⅲ) complex Sm2(C7H4ClCOO)6(C12H8N2)2(H2O)2 (1) with samarium(Ⅲ) nitrate, m-chlorobenzoic acid and 1, 10-phenanthroline(phen) was synthe-sized. It crystallizes in the triclinic space group P\begin{document}$ \overline 1 $\end{document}
A new binuclear cage-like samarium(Ⅲ) complex Sm2(C7H4ClCOO)6(C12H8N2)2(H2O)2 (1) with samarium(Ⅲ) nitrate, m-chlorobenzoic acid and 1, 10-phenanthroline(phen) was synthe-sized. It crystallizes in the triclinic space group P
2020, 39(2): 356-367
doi: 10.14102/j.cnki.0254–5861.2011–2633
Abstract:
Cd(Ⅱ), Co(Ⅱ), Cu(Ⅱ) and Zn(Ⅱ) complexes (1~4) based on 2-(2-pyridyl)benzi-midazole (pbm) and 4, 4΄-oxybisbenzoic acid (H2odc) were synthesized. The formulas of these complexes are [Cd(pbm)(odc)2] (1), [Co(pbm)(odc)2] (2), [Cu(pbm)(odc)2] (3) and [Zn(pbm)(odc)2] (4) confirmed by single-crystal X-ray diffraction analysis, which shows that complexes 1, 2 and 4 belong to monoclinic system with space group P21/n, while complex 3 belongs to monoclinic system with space group P21/c. The binding properties of complexes 1~4 with CT-DNA are evaluated by ultraviolet spectrum, fluorescence spectra and viscosity measurements. The results indicate that complexes 1~4 have strong interaction with CT-DNA binding. These complexes exhibit an electrostatic or groove mode in respect of binding with DNA, which can effectively destroy DNA. And this binding mode may be applied to the interaction between the complexes and cancer cell DNA. Therefore, we hope to provide a theoretical and scientific basis for the research of anti-cancer drugs.
Cd(Ⅱ), Co(Ⅱ), Cu(Ⅱ) and Zn(Ⅱ) complexes (1~4) based on 2-(2-pyridyl)benzi-midazole (pbm) and 4, 4΄-oxybisbenzoic acid (H2odc) were synthesized. The formulas of these complexes are [Cd(pbm)(odc)2] (1), [Co(pbm)(odc)2] (2), [Cu(pbm)(odc)2] (3) and [Zn(pbm)(odc)2] (4) confirmed by single-crystal X-ray diffraction analysis, which shows that complexes 1, 2 and 4 belong to monoclinic system with space group P21/n, while complex 3 belongs to monoclinic system with space group P21/c. The binding properties of complexes 1~4 with CT-DNA are evaluated by ultraviolet spectrum, fluorescence spectra and viscosity measurements. The results indicate that complexes 1~4 have strong interaction with CT-DNA binding. These complexes exhibit an electrostatic or groove mode in respect of binding with DNA, which can effectively destroy DNA. And this binding mode may be applied to the interaction between the complexes and cancer cell DNA. Therefore, we hope to provide a theoretical and scientific basis for the research of anti-cancer drugs.
2020, 39(2): 368-374
doi: 10.14102/j.cnki.0254–5861.2011–2417
Abstract:
Two new copper-organic frameworks [Cu4(L1)4(DMF)4·2DMF]n (DZ-1) and [Cu(L2)(DMF)]n (DZ-2) (H2L1 = 2, 2'-(1, 4-phenylenebis(methylene))bis(sulfanediyl)dinicotinic acid and H2L2 = 2, 2'-(1, 2-phenylenebis(methylene))bis(sulfanediyl)dinicotinic acid) have been synthesized and characterized. DZ-1 with a zero-dimensional structure crystallizes in monoclinic crystal system, space group P21/n with a = 17.1697(11), b = 17.1241(11), c = 18.8638(14) Å, V = 5193.2(6) Å3, Z = 2, Dc = 1.493 g·cm-3, μ = 1.046 mm-1, F(000) = 2408. All L1 ligands adopted syn-conformation. DZ-2 is a two-dimensional structure crystallized in monoclinic crystal system, space group P21/n with a = 11.855(5), b = 18.601(8), c = 12.319(5) Å, V = 2400.4(18) Å3, Z = 4, Dc = 1.514 g·cm-3, μ = 1.124 mm-1, F(000) = 1124. The selective sorption of CO2 over N2 for DZ-1 was found.
Two new copper-organic frameworks [Cu4(L1)4(DMF)4·2DMF]n (DZ-1) and [Cu(L2)(DMF)]n (DZ-2) (H2L1 = 2, 2'-(1, 4-phenylenebis(methylene))bis(sulfanediyl)dinicotinic acid and H2L2 = 2, 2'-(1, 2-phenylenebis(methylene))bis(sulfanediyl)dinicotinic acid) have been synthesized and characterized. DZ-1 with a zero-dimensional structure crystallizes in monoclinic crystal system, space group P21/n with a = 17.1697(11), b = 17.1241(11), c = 18.8638(14) Å, V = 5193.2(6) Å3, Z = 2, Dc = 1.493 g·cm-3, μ = 1.046 mm-1, F(000) = 2408. All L1 ligands adopted syn-conformation. DZ-2 is a two-dimensional structure crystallized in monoclinic crystal system, space group P21/n with a = 11.855(5), b = 18.601(8), c = 12.319(5) Å, V = 2400.4(18) Å3, Z = 4, Dc = 1.514 g·cm-3, μ = 1.124 mm-1, F(000) = 1124. The selective sorption of CO2 over N2 for DZ-1 was found.
2020, 39(2): 340-349
doi: 10.14102/j.cnki.0254–5861.2011–2406
Abstract:
Three new metal-organic complexes, namely [Zn(POA)2(H2O)2] (1), [Zn(POA)2(H2O)2]·2H2O (2) and [Zn(POA)2]n (3), have been synthesized by organic ligand 2-carboxylic acid-4-nitropyridine-1-oxide (POA) and zinc(Ⅱ) ions. The structures of complexes 1~3 are characterized by single-crystal X-ray analysis, XRD powder diffraction analysis, infrared spectroscopy and thermal stability analysis method. Complex 1 belongs to monoclinic system, space group C2/c with a = 22.8215(15), b = 7.5613(16), c = 10.048(3) Å, β = 109.47°, V = 1634.7(6) Å3, Z = 4, F(000) = 944, Dc = 1.900 g/cm3, C12H10N4O12Zn, Mr = 467.61 and μ = 1.584 mm-1. The whole molecule presents "V" shape. Complex 2 is a centrosymmetric structure in triclinic system with space group P\begin{document}$ \overline 1 $\end{document}
Three new metal-organic complexes, namely [Zn(POA)2(H2O)2] (1), [Zn(POA)2(H2O)2]·2H2O (2) and [Zn(POA)2]n (3), have been synthesized by organic ligand 2-carboxylic acid-4-nitropyridine-1-oxide (POA) and zinc(Ⅱ) ions. The structures of complexes 1~3 are characterized by single-crystal X-ray analysis, XRD powder diffraction analysis, infrared spectroscopy and thermal stability analysis method. Complex 1 belongs to monoclinic system, space group C2/c with a = 22.8215(15), b = 7.5613(16), c = 10.048(3) Å, β = 109.47°, V = 1634.7(6) Å3, Z = 4, F(000) = 944, Dc = 1.900 g/cm3, C12H10N4O12Zn, Mr = 467.61 and μ = 1.584 mm-1. The whole molecule presents "V" shape. Complex 2 is a centrosymmetric structure in triclinic system with space group P
