Login In
2016 Volume 32 Issue 3
2016, 32(3): 377-385
doi: 10.11862/CJIC.2016.026
Abstract:
Based on the crystal structure of spinel, we applied the thermodynamic ternary sublattices model to investigate the site occupancy ordering behaviors of Zn2+, Ni2+, Mn2+ and Fe3+ on the 8a and 16d sublattices in the ZnxMn1-xFe2O4 and NixMn1-xFe2O4 by combining thermodynamic calculations with first-principles calculations. Our results suggest that in the manganese ferrites, Mn2+ occupies the 8a sublattice completely, and Fe3+ occupies the 16d sublattice at room temperature, which belongs to a normal spinel. The site configuration is (Fe0.093+Mn0.912+) [Fe1.913+Mn0.092+]O4, when the ferrite is subjected to the heat treatment of 1 273 K. When the temperature increases to 1 473 K, the site configuration is (Fe0.113+Mn0.892+)[Fe1.893+Mn0.112+]O4, which agrees well with the available reliable experimental results. In the zinc ferrites, Zn2+ occupies the 8a sublattice completely, and Fe3+ completely occupies the 16d sublattice at room temperature. It also belongs to normal spinel, and the cations trend to exchange the site occupancy each other at higher temperature. In the Ni ferrites, all Ni2+ occupies the 16d sublattice, and the Fe3+ cations occupy both the 8a and the 16d sublattices, which agrees with the experimental results. It belongs to an inverse spinel. Then, the relationship between the occupancy behaviors and the composition, as well as the heat treatment temperature in the ZnxMn1-xFe2O4 and NixMn1-xFe2O4 were established based on theoretically predictions.
Based on the crystal structure of spinel, we applied the thermodynamic ternary sublattices model to investigate the site occupancy ordering behaviors of Zn2+, Ni2+, Mn2+ and Fe3+ on the 8a and 16d sublattices in the ZnxMn1-xFe2O4 and NixMn1-xFe2O4 by combining thermodynamic calculations with first-principles calculations. Our results suggest that in the manganese ferrites, Mn2+ occupies the 8a sublattice completely, and Fe3+ occupies the 16d sublattice at room temperature, which belongs to a normal spinel. The site configuration is (Fe0.093+Mn0.912+) [Fe1.913+Mn0.092+]O4, when the ferrite is subjected to the heat treatment of 1 273 K. When the temperature increases to 1 473 K, the site configuration is (Fe0.113+Mn0.892+)[Fe1.893+Mn0.112+]O4, which agrees well with the available reliable experimental results. In the zinc ferrites, Zn2+ occupies the 8a sublattice completely, and Fe3+ completely occupies the 16d sublattice at room temperature. It also belongs to normal spinel, and the cations trend to exchange the site occupancy each other at higher temperature. In the Ni ferrites, all Ni2+ occupies the 16d sublattice, and the Fe3+ cations occupy both the 8a and the 16d sublattices, which agrees with the experimental results. It belongs to an inverse spinel. Then, the relationship between the occupancy behaviors and the composition, as well as the heat treatment temperature in the ZnxMn1-xFe2O4 and NixMn1-xFe2O4 were established based on theoretically predictions.
2016, 32(3): 386-392
doi: 10.11862/CJIC.2016.061
Abstract:
Reaction method of Zn2+ on the zinc electrode was researched by cyclic voltammetry (CV). Nucleation mode with Zn2+ was studied by chronoammperometry (CA) and impedance′s behavior of the Zn2+ in the different overpotential deposition periods was investigated by electrochemical impedance spectroscopy (EIS) in Zn (Ⅱ)-NH4Cl quasi neutral system. The results showed that the electrodeposition of Zn2+ is an irreversible electrode reactions and conducts by continuous two steps of single electron in which the first step is controlled by speed. The electron transfer coefficient of electrode reaction is related to the surface of zinc electrode structure. Under the condition of constant potential, the crystallization of Zn2+ is approximate to three-dimensional instantaneous nucleation on zinc electrode in this system. Depositing of Zn2+ has experienced the process of covering, adsorption film and the formation of large number of nucleation. The process was controlled by electrochemical polarization firstly and then the electrochemical polarization-concentration polarization mixed control with the control potential negatively shifted. Finally the mechanism of electrodeposition process with Zn2+ on the zinc electrode was given.
Reaction method of Zn2+ on the zinc electrode was researched by cyclic voltammetry (CV). Nucleation mode with Zn2+ was studied by chronoammperometry (CA) and impedance′s behavior of the Zn2+ in the different overpotential deposition periods was investigated by electrochemical impedance spectroscopy (EIS) in Zn (Ⅱ)-NH4Cl quasi neutral system. The results showed that the electrodeposition of Zn2+ is an irreversible electrode reactions and conducts by continuous two steps of single electron in which the first step is controlled by speed. The electron transfer coefficient of electrode reaction is related to the surface of zinc electrode structure. Under the condition of constant potential, the crystallization of Zn2+ is approximate to three-dimensional instantaneous nucleation on zinc electrode in this system. Depositing of Zn2+ has experienced the process of covering, adsorption film and the formation of large number of nucleation. The process was controlled by electrochemical polarization firstly and then the electrochemical polarization-concentration polarization mixed control with the control potential negatively shifted. Finally the mechanism of electrodeposition process with Zn2+ on the zinc electrode was given.
2016, 32(3): 393-404
doi: 10.11862/CJIC.2016.033
Abstract:
Photodynamic therapy (PDT), as a fast developing alternative of traditional therapeutics, is showing great promise in antitumor treatment. Herein, novel photosensitizer (PS) Fe3O4-TiO2 magnetic nanoparticles (NPs) were strategically designed as targeting drug with higher photocatalytic killing efficiency. The photokilling effect of Fe3O4-TiO2 NPs on hepatoma carcinoma cells (HepG2) in different external magnetic fields was investigated under ultraviolet light and visible light irradiation. Meanwhile, changes of cell cycle, apoptosis rate and mitochondrial membrane potential (MMP) of HepG2 cells were detected by flow cytometry (FCM). The results indicated that Fe3O4-TiO2 NPs have comparable photokilling efficiency to HepG2 cells under both visible and ultraviolet light. Moreover, Fe3O4-TiO2 NPs have higher cell uptake efficiency than pure TiO2, which made it possible to have higher selectivity and photocatalytic killing efficiency. The mechanism was that photocatalytic Fe3O4-TiO2 NPs inhibit cancer cells by yielding reactive oxygen species (ROS). Then, Fe3O4-TiO2 induced apoptosis, mediated by arresting cell cycle in G0/G1 phase, reducing mitochondrial membrane potential, and mitochondrial depolarization.
Photodynamic therapy (PDT), as a fast developing alternative of traditional therapeutics, is showing great promise in antitumor treatment. Herein, novel photosensitizer (PS) Fe3O4-TiO2 magnetic nanoparticles (NPs) were strategically designed as targeting drug with higher photocatalytic killing efficiency. The photokilling effect of Fe3O4-TiO2 NPs on hepatoma carcinoma cells (HepG2) in different external magnetic fields was investigated under ultraviolet light and visible light irradiation. Meanwhile, changes of cell cycle, apoptosis rate and mitochondrial membrane potential (MMP) of HepG2 cells were detected by flow cytometry (FCM). The results indicated that Fe3O4-TiO2 NPs have comparable photokilling efficiency to HepG2 cells under both visible and ultraviolet light. Moreover, Fe3O4-TiO2 NPs have higher cell uptake efficiency than pure TiO2, which made it possible to have higher selectivity and photocatalytic killing efficiency. The mechanism was that photocatalytic Fe3O4-TiO2 NPs inhibit cancer cells by yielding reactive oxygen species (ROS). Then, Fe3O4-TiO2 induced apoptosis, mediated by arresting cell cycle in G0/G1 phase, reducing mitochondrial membrane potential, and mitochondrial depolarization.
2016, 32(3): 414-420
doi: 10.11862/CJIC.2016.048
Abstract:
The extraction behavior of Eu3+ and UO22+ from nitric acid solution with n-Octyl (phenyl)-N, N diisobu-tylcarbamoylmethylphosphine oxide (CMPO) dissolved in hydrophobic ionic liquid [Cnmim][NTf2] (n=2, 8, 12) was studied. The extraction efficiency (E) of Eu3+ and UO22+ in CMPO/[Cnmim][NTf2] was measured as a function of various parameters such as contact time, the concentrations of nitric acid, CMPO and temperature. CMPO/[C2mim][NTf2] system was selected for lanthanide and actinide partitioning from simulated high level waste (SHLW). The results showed that the extraction equilibrium time extended gradually with the increasing of the chain length of the ionic liquid. The E values for Eu3+ decreased while that for UO22+ increased with the increasing of acidity. The extraction process was endothermic for UO22+ while the same was for Eu3+ it was exothermic. The extraction mechanism was suggested that the extraction proceed via ion exchange mechanism for Eu3+ while that for UO22+ via neutral complex. Actinides (An) and lanthanides (Ln) could be extracted effectively from SHLW. And to some extent, An/Ln separation effectiveness was observed under high acidity using CMPO/[C2mim][NTf2] system.
The extraction behavior of Eu3+ and UO22+ from nitric acid solution with n-Octyl (phenyl)-N, N diisobu-tylcarbamoylmethylphosphine oxide (CMPO) dissolved in hydrophobic ionic liquid [Cnmim][NTf2] (n=2, 8, 12) was studied. The extraction efficiency (E) of Eu3+ and UO22+ in CMPO/[Cnmim][NTf2] was measured as a function of various parameters such as contact time, the concentrations of nitric acid, CMPO and temperature. CMPO/[C2mim][NTf2] system was selected for lanthanide and actinide partitioning from simulated high level waste (SHLW). The results showed that the extraction equilibrium time extended gradually with the increasing of the chain length of the ionic liquid. The E values for Eu3+ decreased while that for UO22+ increased with the increasing of acidity. The extraction process was endothermic for UO22+ while the same was for Eu3+ it was exothermic. The extraction mechanism was suggested that the extraction proceed via ion exchange mechanism for Eu3+ while that for UO22+ via neutral complex. Actinides (An) and lanthanides (Ln) could be extracted effectively from SHLW. And to some extent, An/Ln separation effectiveness was observed under high acidity using CMPO/[C2mim][NTf2] system.
2016, 32(3): 427-433
doi: 10.11862/CJIC.2016.047
Abstract:
The graphite oxide samples with different oxidation degree were prepared by modified Hummuers method. The kinds and content of oxygen containing functional groups, structure and cation exchange capacity for the experiment process samples were characterized by XRD, FTIR and XPS. The results show: graphite structure layer oxidized have various oxygen-bearing functional groups such as hydroxyl group (C-OH), carboxy group (-COOH) and epoxy group (C-O-C); with the increase of the degree of oxidation, graphite structures gradually and completely converted to the structure of graphite oxide. The content of C-O-C and-COOH increases gradually, and the content of C-OH first increases then decreases. With the increase of the oxidation degree, the cation exchange capacity of graphite oxide samples also increase firstly and then decrease, corresponding to the maximum value of 1.70, 4.50 and 3.80 mmol·g-1. The C-OH in the carbon basal plane is protonated and H+ is generated at the same time. The H+ can exchange with other cations in the interlayer of graphite oxide. The content of C-OH is the main factor affecting the cation exchange capacity of graphite oxide, and the cation exchange capacity of graphite oxide samples increase with the increase of the content of C-OH.
The graphite oxide samples with different oxidation degree were prepared by modified Hummuers method. The kinds and content of oxygen containing functional groups, structure and cation exchange capacity for the experiment process samples were characterized by XRD, FTIR and XPS. The results show: graphite structure layer oxidized have various oxygen-bearing functional groups such as hydroxyl group (C-OH), carboxy group (-COOH) and epoxy group (C-O-C); with the increase of the degree of oxidation, graphite structures gradually and completely converted to the structure of graphite oxide. The content of C-O-C and-COOH increases gradually, and the content of C-OH first increases then decreases. With the increase of the oxidation degree, the cation exchange capacity of graphite oxide samples also increase firstly and then decrease, corresponding to the maximum value of 1.70, 4.50 and 3.80 mmol·g-1. The C-OH in the carbon basal plane is protonated and H+ is generated at the same time. The H+ can exchange with other cations in the interlayer of graphite oxide. The content of C-OH is the main factor affecting the cation exchange capacity of graphite oxide, and the cation exchange capacity of graphite oxide samples increase with the increase of the content of C-OH.
2016, 32(3): 434-440
doi: 10.11862/CJIC.2016.043
Abstract:
Newly designed [ONO] tridentate hydrazone Schiff base ligand H2Brsth, derived from the condensation of 5-bromosalicylaldehyde and thiophene-2-formyl hydrazine, hydrothermally reacted with metal acetates and phenanthroline as co-ligand yielding two complexes [Cd2(μ-Brsth)2(Phen)2] (1) and [Cu (Brsth)(Phen)] (2), which were characterized by elemental analyses, FT-IR, electronic spectra, fluorescence spectra, TGA and single crystal X-ray diffraction. The X-ray diffraction analyses reveal that complex 1 crystallizes in monoclinic space group C2/c with a=2.116 36(13) nm, b=1.163 35(7) nm, c=1.872 43(12) nm, β=100.981(2)°, V=4.525 6(5) nm3 and Z=4, while 2 crystallizes in the triclinic space group P1 with a=0.911 7(2) nm, b=1.089 4(3) nm, c=1.272 9(3) nm, α=64.923(4)°, β=82.006(5)°, γ=67.768(5)°, V=1.059 6(5) nm3 and Z=2. The complex 1 is a binuclear ternary complex, in which Cd atoms locate in distorted coordination octahedron. The complex 2 is a mononuclear ternary complex with Cu atom in distorted square pyramidal coordination. The complex 1 exhibits strong green fluorescence with emission maximum of 525 nm at the excitation wavelength of 443 nm, while the ligand shows emission at 475 nm. CCDC: 1062986, 1; 1046224, 2.
Newly designed [ONO] tridentate hydrazone Schiff base ligand H2Brsth, derived from the condensation of 5-bromosalicylaldehyde and thiophene-2-formyl hydrazine, hydrothermally reacted with metal acetates and phenanthroline as co-ligand yielding two complexes [Cd2(μ-Brsth)2(Phen)2] (1) and [Cu (Brsth)(Phen)] (2), which were characterized by elemental analyses, FT-IR, electronic spectra, fluorescence spectra, TGA and single crystal X-ray diffraction. The X-ray diffraction analyses reveal that complex 1 crystallizes in monoclinic space group C2/c with a=2.116 36(13) nm, b=1.163 35(7) nm, c=1.872 43(12) nm, β=100.981(2)°, V=4.525 6(5) nm3 and Z=4, while 2 crystallizes in the triclinic space group P1 with a=0.911 7(2) nm, b=1.089 4(3) nm, c=1.272 9(3) nm, α=64.923(4)°, β=82.006(5)°, γ=67.768(5)°, V=1.059 6(5) nm3 and Z=2. The complex 1 is a binuclear ternary complex, in which Cd atoms locate in distorted coordination octahedron. The complex 2 is a mononuclear ternary complex with Cu atom in distorted square pyramidal coordination. The complex 1 exhibits strong green fluorescence with emission maximum of 525 nm at the excitation wavelength of 443 nm, while the ligand shows emission at 475 nm. CCDC: 1062986, 1; 1046224, 2.
2016, 32(3): 441-449
doi: 10.11862/CJIC.2016.053
Abstract:
Co-Pi is a cheap and high efficient co-catalyst for water splitting. The impregnation method of co-catalyst is very important for water splitting property of photoanode. Therefore, in this work, for Ta3N5 photoanode, a series of studies about co-catalyst Co-Pi impregnation by light assisted electrodeposition have been developed. The results suggest that the incident light intensity during the Co-Pi impregnation process has little effect on the water splitting property, while the loading potential and the loading charge have great influence on the water splitting property of Ta3N5. In addition, the transfer of carriers on Ta3N5/electrolyte interface has been studied by electrochemical impedance spectroscopy test and simulation. The results suggest that the photo-generated carriers transfer can be efficiently regulated by controlling the loading potential and loading charge during the impregnation process to improve the water splitting property of Ta3N5. More importantly, the best loading potential of Co-Pi keeps almost unchanged for Ta3N5 with different roughness, while the best loading charge has positive correlation with the surface roughness of the phtoanode, therefore, the loading charge should be adjusted by the roughness of photoanode.
Co-Pi is a cheap and high efficient co-catalyst for water splitting. The impregnation method of co-catalyst is very important for water splitting property of photoanode. Therefore, in this work, for Ta3N5 photoanode, a series of studies about co-catalyst Co-Pi impregnation by light assisted electrodeposition have been developed. The results suggest that the incident light intensity during the Co-Pi impregnation process has little effect on the water splitting property, while the loading potential and the loading charge have great influence on the water splitting property of Ta3N5. In addition, the transfer of carriers on Ta3N5/electrolyte interface has been studied by electrochemical impedance spectroscopy test and simulation. The results suggest that the photo-generated carriers transfer can be efficiently regulated by controlling the loading potential and loading charge during the impregnation process to improve the water splitting property of Ta3N5. More importantly, the best loading potential of Co-Pi keeps almost unchanged for Ta3N5 with different roughness, while the best loading charge has positive correlation with the surface roughness of the phtoanode, therefore, the loading charge should be adjusted by the roughness of photoanode.
2016, 32(3): 450-456
doi: 10.11862/CJIC.2016.070
Abstract:
In hydrothermal synthesis system, with triethylamine (TEA) and tetraethyl ammonium hydroxide (TEAOH) as the mixed template agent, the influence of the manner of adding aluminum in the preparation of the initial gel on the SAPO-34 molecular sieves synthesis and the catalytic performances of methanol to olefins (MTO) reaction was investigated. The products were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Nitrogen isothermal adsorption stripping (BET), 29Si MAS NMR and NH3-TPD. The catalytic performances of methanol to olefins (MTO) were also investigated. The results showed that the particle size of SAPO-34 molecular sieve became smaller and the cubic morphology gradually turned into sheet-like, with the increased of the first addition amount of aluminum, and the proportion of Si (4Al) species in the as-synthesized SAPO-34 increased, the amount of strong acidity and the acid density also increased. The results also showed that the lifetime of SAPO-34 molecular sieve in MTO reaction is gradually extended, the ethylene selectivity decreases and the propylene selectivity increases with the increasing of the first addition amount of aluminum source.
In hydrothermal synthesis system, with triethylamine (TEA) and tetraethyl ammonium hydroxide (TEAOH) as the mixed template agent, the influence of the manner of adding aluminum in the preparation of the initial gel on the SAPO-34 molecular sieves synthesis and the catalytic performances of methanol to olefins (MTO) reaction was investigated. The products were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Nitrogen isothermal adsorption stripping (BET), 29Si MAS NMR and NH3-TPD. The catalytic performances of methanol to olefins (MTO) were also investigated. The results showed that the particle size of SAPO-34 molecular sieve became smaller and the cubic morphology gradually turned into sheet-like, with the increased of the first addition amount of aluminum, and the proportion of Si (4Al) species in the as-synthesized SAPO-34 increased, the amount of strong acidity and the acid density also increased. The results also showed that the lifetime of SAPO-34 molecular sieve in MTO reaction is gradually extended, the ethylene selectivity decreases and the propylene selectivity increases with the increasing of the first addition amount of aluminum source.
2016, 32(3): 457-463
doi: 10.11862/CJIC.2016.075
Abstract:
Open-framework aluminophosphates (AlPOs) is an important family of the porous crystal materials. However, the synthesis of the Open-framework aluminophosphates is affected by many parameters, such as reaction material, gel composition, solvent, template agent, crystallization temperature and crystallization time etc. Based on the ALPOs synthesis database, which established by the State Key Laboratory of Inorganic Synthesis and Preparative Chemistry of Jilin University, the work in this paper concentrates on analyzing the relationship between the synthetic parameters and the final product. In order to take both the importance and correlation of the features into consideration in the synthetic parameter analysis, we apply Maximum Weight and Minimum Redundancy (MWMR) to analyze the impact of solvent parameters and template parameters for the rational synthesis of (8, 6)-ring-containing AlPOs. The effectiveness of the method is demonstrated by extensive experiments. Furthermore, we also make some deep analyses about the relationship between the synthetic parameters and final products.The experimental results show that the geometric parameters of the of organic template, the nC/nN and the dipole moment of the solvent etc. may impact most for the final product of this kind of open-framework aluminophosphates.
Open-framework aluminophosphates (AlPOs) is an important family of the porous crystal materials. However, the synthesis of the Open-framework aluminophosphates is affected by many parameters, such as reaction material, gel composition, solvent, template agent, crystallization temperature and crystallization time etc. Based on the ALPOs synthesis database, which established by the State Key Laboratory of Inorganic Synthesis and Preparative Chemistry of Jilin University, the work in this paper concentrates on analyzing the relationship between the synthetic parameters and the final product. In order to take both the importance and correlation of the features into consideration in the synthetic parameter analysis, we apply Maximum Weight and Minimum Redundancy (MWMR) to analyze the impact of solvent parameters and template parameters for the rational synthesis of (8, 6)-ring-containing AlPOs. The effectiveness of the method is demonstrated by extensive experiments. Furthermore, we also make some deep analyses about the relationship between the synthetic parameters and final products.The experimental results show that the geometric parameters of the of organic template, the nC/nN and the dipole moment of the solvent etc. may impact most for the final product of this kind of open-framework aluminophosphates.
2016, 32(3): 464-468
doi: 10.11862/CJIC.2016.056
Abstract:
The Schiff base compound H4L was synthesized from condensation reaction of 4-Methoxysalicylaldeh-yde with Pentaerythrityltetramine. H4L was reacted with Ni (ClO4)2·6H2O or Cu (ClO4)2·6H2O to give two complexes [Ni2(L)]·DMF (1) and [Cu4(L)2(DMSO)3]·2DMSO (2). The complexes were characterized by elemental analysis, FT-IR and single crystal X-ray diffraction. The crystals of 1 and 2 belong to the triclinic system, space group P1. The complexes 1 and 2 are all binuclear complexes. The In vitro bacteriostatic activities of the ligand and complexes were tested against several kinds of bacteria. The results show that the ligand and complexes possess different bacteriostatic activities to S. aureus. CCDC: 1436577, H4L; 1436578, 1; 1436576, 2.
The Schiff base compound H4L was synthesized from condensation reaction of 4-Methoxysalicylaldeh-yde with Pentaerythrityltetramine. H4L was reacted with Ni (ClO4)2·6H2O or Cu (ClO4)2·6H2O to give two complexes [Ni2(L)]·DMF (1) and [Cu4(L)2(DMSO)3]·2DMSO (2). The complexes were characterized by elemental analysis, FT-IR and single crystal X-ray diffraction. The crystals of 1 and 2 belong to the triclinic system, space group P1. The complexes 1 and 2 are all binuclear complexes. The In vitro bacteriostatic activities of the ligand and complexes were tested against several kinds of bacteria. The results show that the ligand and complexes possess different bacteriostatic activities to S. aureus. CCDC: 1436577, H4L; 1436578, 1; 1436576, 2.
2016, 32(3): 483-490
doi: 10.11862/CJIC.2016.065
Abstract:
BiVO4/BiPO4 composites with different nV/nP molar ratios were synthesized by a simple one-pot hydrothermal method. The nV/nP molar ratios were 0.1/9.9, 0.5/9.5, 1/9, 3/7, and 5/5, respectively. The BiVO4/BiPO4 composites were characterized by X-ray diffraction, field emission scanning electron microscope, energy-dispersive spectroscopy, Raman spectrum, UV-Vis spectrophotometer, UV-Vis diffuse reflectance spectroscopy, and electrochemical impedance spectra. The photocatalytic activities of BiVO4/BiPO4 composites were evaluated by the degradation of methylene blue (MB) under visible light irradiation (λ>420 nm). When the ratios of the BiVO4/BiPO4 composites were less than 3/7, the photocatalytic activities of BiVO4/BiPO4 composites were enhanced with an increasing amount of BiVO4. The result showed that the BiVO4/BiPO4 composite ratio for nV/nP=3/7 possessed the highest photocatalytic activity. The BiVO4/BiPO4 composite ratio for nV/nP=3/7 possessed the maximal k value of 0.005 1 min-1. It is 23.2 times of the pure BiPO4. The photocatalytic mechanism of the BiVO4/BiPO4 composites could be mainly ascribed to the existence of BiVO4 which could accelerate the separation and migration efficiency of photogenerated carriers.
BiVO4/BiPO4 composites with different nV/nP molar ratios were synthesized by a simple one-pot hydrothermal method. The nV/nP molar ratios were 0.1/9.9, 0.5/9.5, 1/9, 3/7, and 5/5, respectively. The BiVO4/BiPO4 composites were characterized by X-ray diffraction, field emission scanning electron microscope, energy-dispersive spectroscopy, Raman spectrum, UV-Vis spectrophotometer, UV-Vis diffuse reflectance spectroscopy, and electrochemical impedance spectra. The photocatalytic activities of BiVO4/BiPO4 composites were evaluated by the degradation of methylene blue (MB) under visible light irradiation (λ>420 nm). When the ratios of the BiVO4/BiPO4 composites were less than 3/7, the photocatalytic activities of BiVO4/BiPO4 composites were enhanced with an increasing amount of BiVO4. The result showed that the BiVO4/BiPO4 composite ratio for nV/nP=3/7 possessed the highest photocatalytic activity. The BiVO4/BiPO4 composite ratio for nV/nP=3/7 possessed the maximal k value of 0.005 1 min-1. It is 23.2 times of the pure BiPO4. The photocatalytic mechanism of the BiVO4/BiPO4 composites could be mainly ascribed to the existence of BiVO4 which could accelerate the separation and migration efficiency of photogenerated carriers.
2016, 32(3): 491-498
doi: 10.11862/CJIC.2016.051
Abstract:
Powder and pellet samples of YAlO3 with various defect concentrations were prepared using conventional solid state reactions at 1 450 ℃, followed by annealing in air, O2 or N2 atmospheres at various temperatures. The correlation between the body-color of the samples and the defect equilibria was investigated by diffuse-reflection spectra and AC impedance data. The results indicate that YAlO3 has p-type conduction and its light-brown body-color is caused by the cation vacancies. Annealing YAlO3 at high temperature in N2 atmosphere may reduce the defect concentration and the body-color. By the first-principle calculations, it is proposed that the Al vacancies VAl× may be the dominant defects in YAlO3.
Powder and pellet samples of YAlO3 with various defect concentrations were prepared using conventional solid state reactions at 1 450 ℃, followed by annealing in air, O2 or N2 atmospheres at various temperatures. The correlation between the body-color of the samples and the defect equilibria was investigated by diffuse-reflection spectra and AC impedance data. The results indicate that YAlO3 has p-type conduction and its light-brown body-color is caused by the cation vacancies. Annealing YAlO3 at high temperature in N2 atmosphere may reduce the defect concentration and the body-color. By the first-principle calculations, it is proposed that the Al vacancies VAl× may be the dominant defects in YAlO3.
2016, 32(3): 499-507
doi: 10.11862/CJIC.2016.068
Abstract:
Spherical LiNi0.5Mn1.5O4@Li3PO4 composite was prepared by a co-precipitation method. The structure and electrochemical performance were investigated by X-ray powder diffraction (XRD), scanning electron microscope (SEM), FT-IR spectroscopy, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and charge-discharge measurements. XRD and SEM shows that Li3PO4 coating influence the lattice parameter of LiNi0.5Mn1.5O4 composed of spherical particle size. CV and EIS imply that 5% (mass percent) Li3PO4-coated LiNi0.5Mn1.5O4 has higher reversible intercalation and deintercalation of Li+, larger lithium-ion diffusion coefficient and smaller charge transfer resistance corresponding to a much higher conductivity than those of pristine LiNi0.5Mn1.5O4 corresponding to the extraction of Li+ ions. Charge-discharge test reveals that the in situ Li3PO4 modifying improves the electronic conductivity of the electrode in the local environment, electrochemical activity, and then results in their relatively higher capacity at high charge-discharge rate. The enhanced performance of 5% (mass percent) Li3PO4-coated LiNi0.5Mn1.5O4 is ascribed to the improved electronic conduction and the reduced polarization resulting from the Li3PO4 modification together with sphere-like particles composed of nano particle LiNi0.5Mn1.5O4.
Spherical LiNi0.5Mn1.5O4@Li3PO4 composite was prepared by a co-precipitation method. The structure and electrochemical performance were investigated by X-ray powder diffraction (XRD), scanning electron microscope (SEM), FT-IR spectroscopy, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and charge-discharge measurements. XRD and SEM shows that Li3PO4 coating influence the lattice parameter of LiNi0.5Mn1.5O4 composed of spherical particle size. CV and EIS imply that 5% (mass percent) Li3PO4-coated LiNi0.5Mn1.5O4 has higher reversible intercalation and deintercalation of Li+, larger lithium-ion diffusion coefficient and smaller charge transfer resistance corresponding to a much higher conductivity than those of pristine LiNi0.5Mn1.5O4 corresponding to the extraction of Li+ ions. Charge-discharge test reveals that the in situ Li3PO4 modifying improves the electronic conductivity of the electrode in the local environment, electrochemical activity, and then results in their relatively higher capacity at high charge-discharge rate. The enhanced performance of 5% (mass percent) Li3PO4-coated LiNi0.5Mn1.5O4 is ascribed to the improved electronic conduction and the reduced polarization resulting from the Li3PO4 modification together with sphere-like particles composed of nano particle LiNi0.5Mn1.5O4.
2016, 32(3): 508-516
doi: 10.11862/CJIC.2016.067
Abstract:
4, 4-(9-(n-Hexadecyl) carbazole-3, 6-diyl) di (6-(4-(diphenylamino) phenyl)-2, 2-difluoro-1, 3, 2(2H)-diox-aborine) (named as BDOBC16), a kind of π-conjugated organic molecule containing β-diketone-boron difluoride groups, was assembled in SBA-15 modified with (3-aminopropyl) triethoxysilane (APTES), and fluorine-boron groups in molecule of BDOBC16 was found to be remained in the assembly. Results indicate that the organic compound in silylated SBA-15 emits green light while itself emits red light. The energy of 0.45 eV is found changeable in emission of the guest before and after assembly, and luminescent intensity of BDOBC16 increases 75 times after it was assembled. Strong H-bond existed between the host and the guest, which is regarded as main reason to result tremendous change in luminescence of the guest. Molecular aggregation is also found harmful while high dispersion is benefit to luminescence of the guest.
4, 4-(9-(n-Hexadecyl) carbazole-3, 6-diyl) di (6-(4-(diphenylamino) phenyl)-2, 2-difluoro-1, 3, 2(2H)-diox-aborine) (named as BDOBC16), a kind of π-conjugated organic molecule containing β-diketone-boron difluoride groups, was assembled in SBA-15 modified with (3-aminopropyl) triethoxysilane (APTES), and fluorine-boron groups in molecule of BDOBC16 was found to be remained in the assembly. Results indicate that the organic compound in silylated SBA-15 emits green light while itself emits red light. The energy of 0.45 eV is found changeable in emission of the guest before and after assembly, and luminescent intensity of BDOBC16 increases 75 times after it was assembled. Strong H-bond existed between the host and the guest, which is regarded as main reason to result tremendous change in luminescence of the guest. Molecular aggregation is also found harmful while high dispersion is benefit to luminescence of the guest.
2016, 32(3): 517-526
doi: 10.11862/CJIC.2016.039
Abstract:
CeTiOx and CeZrTiOx catalysts were prepared by co-precipitation method and used for selective catalytic reduction of NOx by NH3 (NH3-SCR). Thermal aging of the two catalysts was conducted at various temperatures to investigate the effect of Zr on thermal stability of CeTiOx catalyst. The NH3-SCR performance of the catalysts showed that the Zr-modified catalyst exhibited better activity and N2 selectivity than CeTiOx catalyst after high temperature aging at 650, 750 and 850 ℃. The XRD, Raman and H2-TPR results illustrated that the addition of Zr could prevent Ce species from sintering and inhibit the formation of rutile TiO2. The SEM images of the catalysts revealed that the aggregation of the particles with increasing calcination temperature could be inhibited by addition of Zr. From the XPS spectra of Ce3d, the ratio of Ce3+/Ce4+ of CeTiOx decreased more sharply than that of CeZrTiOx with the aging temperature, meaning that more crystal defects and oxygen vacancies were preserved after Zr addition, which led to increased catalytic performance. In addition, NH3-TPD results implied that modified catalyst possessed larger amounts of Brönsted acid sites after calcining at a same temperature, improving the activity and inhibiting the NH3 oxidation. Thus, a conclusion could be drawn that Zr addition improved the thermal stability of the CeTiOx catalyst.
CeTiOx and CeZrTiOx catalysts were prepared by co-precipitation method and used for selective catalytic reduction of NOx by NH3 (NH3-SCR). Thermal aging of the two catalysts was conducted at various temperatures to investigate the effect of Zr on thermal stability of CeTiOx catalyst. The NH3-SCR performance of the catalysts showed that the Zr-modified catalyst exhibited better activity and N2 selectivity than CeTiOx catalyst after high temperature aging at 650, 750 and 850 ℃. The XRD, Raman and H2-TPR results illustrated that the addition of Zr could prevent Ce species from sintering and inhibit the formation of rutile TiO2. The SEM images of the catalysts revealed that the aggregation of the particles with increasing calcination temperature could be inhibited by addition of Zr. From the XPS spectra of Ce3d, the ratio of Ce3+/Ce4+ of CeTiOx decreased more sharply than that of CeZrTiOx with the aging temperature, meaning that more crystal defects and oxygen vacancies were preserved after Zr addition, which led to increased catalytic performance. In addition, NH3-TPD results implied that modified catalyst possessed larger amounts of Brönsted acid sites after calcining at a same temperature, improving the activity and inhibiting the NH3 oxidation. Thus, a conclusion could be drawn that Zr addition improved the thermal stability of the CeTiOx catalyst.
2016, 32(3): 527-536
doi: 10.11862/CJIC.2016.052
Abstract:
Porous tremella-like NiO on conductive substrates have been fabricated by a facile chemical bath deposition approach and further investigated as the binder-free electrode for high-performance supercapacitors. The microstructure and morphologies of the resulting materials were characterized by XRD, SEM, TEM, and electrochemical measurements. Owing to the superior electrical conductivity, the porous structure of the NiO microspheres combinated the advantages of each subunit can deliver a high areal capacitance of 3.5 F·cm-2 and a corresponding specific capacitance of 705 F·g-1 at a current density of 0.5 A·g-1, as well as a good rate capability (68.1% capacitance retention from 0.5 A·g-1 to 8 A·g-1), and excellent cycling stability (17.6% capacitance increasing after 3000th cycling at high current density 12 A·g-1).
Porous tremella-like NiO on conductive substrates have been fabricated by a facile chemical bath deposition approach and further investigated as the binder-free electrode for high-performance supercapacitors. The microstructure and morphologies of the resulting materials were characterized by XRD, SEM, TEM, and electrochemical measurements. Owing to the superior electrical conductivity, the porous structure of the NiO microspheres combinated the advantages of each subunit can deliver a high areal capacitance of 3.5 F·cm-2 and a corresponding specific capacitance of 705 F·g-1 at a current density of 0.5 A·g-1, as well as a good rate capability (68.1% capacitance retention from 0.5 A·g-1 to 8 A·g-1), and excellent cycling stability (17.6% capacitance increasing after 3000th cycling at high current density 12 A·g-1).
2016, 32(3): 537-544
doi: 10.11862/CJIC.2016.060
Abstract:
Three Ag (Ⅰ) coordination complexes, namely [Ag (dpq)(NO3)2]n (1), [Ag4 (tppq)2(NO3)4](2) and [Ag6(hpdq)2(NO3)6](3) have been synthesized based on three polypyridyl ligands: 2, 3-di (pyridin-2-yl) quinoxaline (dpq), 2, 3, 7, 8-tetra (pyridine-2-yl) pyrazino[2, 3-g]-quinoxaline (tppq) and 2, 3, 6, 7, 10, 11-hexakis (2-pyridyl) dipyrazino[2, 3-f:2′, 3′-h]quinoxaline) (hpdq), respectively. Single crystal X-ray diffraction analyses reveal that complexes 1~3 assembled based on distinct double-decker unit comprising two respective polypyridyl ligands but four, four, and six Ag (Ⅰ) ions, respectively. Among them, The double-decker units in 1 and 2 both extended to two dimensional net via the coordination interaction between Ag (Ⅰ) and NO3- anion, while that in 3 to three dimensional net via C-H…O hydrogen bond. Furthermore, the coordintion interaciton of polypyridyl ligands and Ag (Ⅰ) ion in solution was also investigated by UV-Vis absorption and fluorescence spectroscopic analyses, which witnesses the much more sensitive spectral response of hpdq to the additon of Ag (Ⅰ) ion than other two ligands. CCDC: 868734, 1; 868735, 2; 790268, 3.
Three Ag (Ⅰ) coordination complexes, namely [Ag (dpq)(NO3)2]n (1), [Ag4 (tppq)2(NO3)4](2) and [Ag6(hpdq)2(NO3)6](3) have been synthesized based on three polypyridyl ligands: 2, 3-di (pyridin-2-yl) quinoxaline (dpq), 2, 3, 7, 8-tetra (pyridine-2-yl) pyrazino[2, 3-g]-quinoxaline (tppq) and 2, 3, 6, 7, 10, 11-hexakis (2-pyridyl) dipyrazino[2, 3-f:2′, 3′-h]quinoxaline) (hpdq), respectively. Single crystal X-ray diffraction analyses reveal that complexes 1~3 assembled based on distinct double-decker unit comprising two respective polypyridyl ligands but four, four, and six Ag (Ⅰ) ions, respectively. Among them, The double-decker units in 1 and 2 both extended to two dimensional net via the coordination interaction between Ag (Ⅰ) and NO3- anion, while that in 3 to three dimensional net via C-H…O hydrogen bond. Furthermore, the coordintion interaciton of polypyridyl ligands and Ag (Ⅰ) ion in solution was also investigated by UV-Vis absorption and fluorescence spectroscopic analyses, which witnesses the much more sensitive spectral response of hpdq to the additon of Ag (Ⅰ) ion than other two ligands. CCDC: 868734, 1; 868735, 2; 790268, 3.
2016, 32(3): 545-554
doi: 10.11862/CJIC.2016.062
Abstract:
The reaction of 3, 5-bis (pyridin-4-ylmethoxy) benzoic acid (HL) and a combination of dicarboxylic acid ligands such as thiophene-2, 5-dicarboxylic acid (H2tdc), 5-hydroxybenzene-1, 3-dicarboxylic acid (H3hdc), 1, 4-benzenedithioacetic acid (H2bdtc) with Zn (Ⅱ) and Cd (Ⅱ) metal ions give rise to four coordination polymers with interpenetrating (3, 4)-connected networks, namely, [Zn2L2(tdc)]n (1), {[Zn4L4(Hhdc)2]·H2O}n (2), {[Zn2L2(Hhdc)]·H2O}n (3), {[Cd2L2(bdtc)(H2O)]· 0.5H2O}n (4). 1~3 exhibit (3, 4)-connected 4-fold-interpenetrating 3D networks with point symbol of (4.82)(4.85) (1), (63)(65.8) (2) and (63)(65.8) (3) topology, respectively. 4 displays a (3, 4)-connected 3-fold-interpenetrating 2D network with (63)(66) topology. Luminescent properties of 1, 3 and 4 were also investigated. CCDC: 852424, 1; 872035, 2; 887738, 3; 872037, 4.
The reaction of 3, 5-bis (pyridin-4-ylmethoxy) benzoic acid (HL) and a combination of dicarboxylic acid ligands such as thiophene-2, 5-dicarboxylic acid (H2tdc), 5-hydroxybenzene-1, 3-dicarboxylic acid (H3hdc), 1, 4-benzenedithioacetic acid (H2bdtc) with Zn (Ⅱ) and Cd (Ⅱ) metal ions give rise to four coordination polymers with interpenetrating (3, 4)-connected networks, namely, [Zn2L2(tdc)]n (1), {[Zn4L4(Hhdc)2]·H2O}n (2), {[Zn2L2(Hhdc)]·H2O}n (3), {[Cd2L2(bdtc)(H2O)]· 0.5H2O}n (4). 1~3 exhibit (3, 4)-connected 4-fold-interpenetrating 3D networks with point symbol of (4.82)(4.85) (1), (63)(65.8) (2) and (63)(65.8) (3) topology, respectively. 4 displays a (3, 4)-connected 3-fold-interpenetrating 2D network with (63)(66) topology. Luminescent properties of 1, 3 and 4 were also investigated. CCDC: 852424, 1; 872035, 2; 887738, 3; 872037, 4.
2016, 32(3): 555-560
doi: 10.11862/CJIC.2016.064
Abstract:
Two complexes [CoL2]Cl·2CH3OH (1) and [CdL2] (2) (HL=(quinolin-8-ylmethylene) thiosemicarbazide) have been synthesized and structurally determined by single-crystal X-ray diffraction. The results show that the metal ion in each complex with a distorted octahedron geometry is surrounded by two anionic thiosemicarbazone ligand with N2S donor set. Complexes 1 and 2 can bind to DNA via electrostatic intercalation and partial intercalation modes, respectively. CCDC: 1436092, 1; 1436093, 2.
Two complexes [CoL2]Cl·2CH3OH (1) and [CdL2] (2) (HL=(quinolin-8-ylmethylene) thiosemicarbazide) have been synthesized and structurally determined by single-crystal X-ray diffraction. The results show that the metal ion in each complex with a distorted octahedron geometry is surrounded by two anionic thiosemicarbazone ligand with N2S donor set. Complexes 1 and 2 can bind to DNA via electrostatic intercalation and partial intercalation modes, respectively. CCDC: 1436092, 1; 1436093, 2.
