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2017 Volume 33 Issue 12
2017, 33(12): 2155-2168
doi: 10.11862/CJIC.2017.263
Abstract:
High temperature lithium battery is the development of low temperature applications of thermal batteries, and has large potential development and utilization in the oil/gas and geothermal field. Compared with the lithium alloy anode materials with large specific capacity and close to the pure lithium electrode potential, the cathode materials are pivotal section of high temperature lithium battery and have large potential space. In the cathode materials, the oxide materials exhibit high voltage characteristics and high thermal stability, and the high-temperature lithium battery can be miniaturized to meet the current voltage supply under the specific conditions. However, there is no systematic overview about the oxide of high-temperature lithium battery currently. In order to make more development in this field and promote the optimal adjustment of energy structure, this paper introduces and summarizes the transition metal oxides used in high-temperature lithium battery, including physical properties, electrochemical properties and synthesis or preparation methods. We describe the excellent properties of various oxide materials in detail, and point out the shortcomings and the existing problems of the material. Moreover, this paper predicts the development of oxide cathode materials, and demonstrates the future direction of development and the work to be done. We hope that this work can provide some reference for the relevant researchers.
High temperature lithium battery is the development of low temperature applications of thermal batteries, and has large potential development and utilization in the oil/gas and geothermal field. Compared with the lithium alloy anode materials with large specific capacity and close to the pure lithium electrode potential, the cathode materials are pivotal section of high temperature lithium battery and have large potential space. In the cathode materials, the oxide materials exhibit high voltage characteristics and high thermal stability, and the high-temperature lithium battery can be miniaturized to meet the current voltage supply under the specific conditions. However, there is no systematic overview about the oxide of high-temperature lithium battery currently. In order to make more development in this field and promote the optimal adjustment of energy structure, this paper introduces and summarizes the transition metal oxides used in high-temperature lithium battery, including physical properties, electrochemical properties and synthesis or preparation methods. We describe the excellent properties of various oxide materials in detail, and point out the shortcomings and the existing problems of the material. Moreover, this paper predicts the development of oxide cathode materials, and demonstrates the future direction of development and the work to be done. We hope that this work can provide some reference for the relevant researchers.
2017, 33(12): 2169-2176
doi: 10.11862/CJIC.2017.280
Abstract:
Three polynuclear manganese(Ⅱ) coordination polymers(CPs), {(H3O)[Mn4(BOABA)2(OH)3(H2O)]·H2O}n (1), {(H3O)4[Mn7(BOABA)4(OH)6(H2O)2]}n (2) and {(H3O)4[Mn7(BOABA)4(OH)4(Cl)2(H2O)2]·2H2O}n (3) (H3BOABA=3, 5-bis-oxyacetate-benzoic acid) have been synthesized under hydrothermal condition and structurally characterized by single crystal X-ray diffraction analyses, XRPD, IR spectra and thermal analyses. CP 1 can be rationalized as a binodal (5, 12)-connected 3D topology network based on tetranuclear[Mn4(μ3-OH)3(COO)10] clusters with point symbol of (32.47.5)2(38.423.514.621). CPs 2 and 3 are isostructural and present binodal (3, 12)-connected 2D topology network based respectively on heptanuclear[Mn7(OH)6(COO)16] and[Mn7(OH)4Cl2(COO)16] clusters with point symbol of (43)4(430.624.812). The cyclic voltammograms of the CPs reveal that the processes of the redox are all irreversible.
Three polynuclear manganese(Ⅱ) coordination polymers(CPs), {(H3O)[Mn4(BOABA)2(OH)3(H2O)]·H2O}n (1), {(H3O)4[Mn7(BOABA)4(OH)6(H2O)2]}n (2) and {(H3O)4[Mn7(BOABA)4(OH)4(Cl)2(H2O)2]·2H2O}n (3) (H3BOABA=3, 5-bis-oxyacetate-benzoic acid) have been synthesized under hydrothermal condition and structurally characterized by single crystal X-ray diffraction analyses, XRPD, IR spectra and thermal analyses. CP 1 can be rationalized as a binodal (5, 12)-connected 3D topology network based on tetranuclear[Mn4(μ3-OH)3(COO)10] clusters with point symbol of (32.47.5)2(38.423.514.621). CPs 2 and 3 are isostructural and present binodal (3, 12)-connected 2D topology network based respectively on heptanuclear[Mn7(OH)6(COO)16] and[Mn7(OH)4Cl2(COO)16] clusters with point symbol of (43)4(430.624.812). The cyclic voltammograms of the CPs reveal that the processes of the redox are all irreversible.
2017, 33(12): 2177-2185
doi: 10.11862/CJIC.2017.269
Abstract:
Two novel silver complexes {[Ag(ttmb)(H2O)]NO3}n (1) and {[Ag(ttmb)]NO3·H2O}n (2) were synthesized by the reaction of AgNO3 with 1, 3, 5-tri(1, 2, 4-triazol-1-ylmethyl)-2, 4, 6-trimethylbenzene (ttmb) in different solvents. The solid-state fluorescent properties of these two complexes and related ligand ttmb were then investigated at room temperature. Structural characterizations by elemental analysis, powder and single-crystal X-ray diffraction analysis and infrared spectra shows that complex 1 contains a highly undulated 2D network while complex 1 carries a 2D (6, 3) network.
Two novel silver complexes {[Ag(ttmb)(H2O)]NO3}n (1) and {[Ag(ttmb)]NO3·H2O}n (2) were synthesized by the reaction of AgNO3 with 1, 3, 5-tri(1, 2, 4-triazol-1-ylmethyl)-2, 4, 6-trimethylbenzene (ttmb) in different solvents. The solid-state fluorescent properties of these two complexes and related ligand ttmb were then investigated at room temperature. Structural characterizations by elemental analysis, powder and single-crystal X-ray diffraction analysis and infrared spectra shows that complex 1 contains a highly undulated 2D network while complex 1 carries a 2D (6, 3) network.
2017, 33(12): 2186-2192
doi: 10.11862/CJIC.2017.259
Abstract:
Imidazole template iron sulfate clusters, [HMIM]2[Fe2O(SO4)3(DMSO)2]·0.5DMSO (1) and[HPIM]4[Fe4O2(SO4)6(DMSO)4]·2MeCN (2), were synthesized via the reaction of FeCl2 with Brønsted acidic ionic liquid[HRIM] [HSO4] using ethanol as solvent. The clusters crystallize in triclinic with a space group P1. The core contains 4 iron atoms, which are coplanar connected by the central μ3-O bridge, μ2-O and μ3-O bridge of SO4 groups. Protonated imidazoliums are the counter cations for the balance of charges of the core. Variable temperature magnetic susceptibility measurements of the Fe4 sulfate clusters reveal weak antiferromagnetic exchange interactions between the metal centers. In contrast, the reaction of FeCl3 under the similar experimental conditions didn't produce the similar cluster structure, whereas iron-DMSO complex[FeCl2(DMSO)4] [EtSO4]·DMSO (3) was obtained.
Imidazole template iron sulfate clusters, [HMIM]2[Fe2O(SO4)3(DMSO)2]·0.5DMSO (1) and[HPIM]4[Fe4O2(SO4)6(DMSO)4]·2MeCN (2), were synthesized via the reaction of FeCl2 with Brønsted acidic ionic liquid[HRIM] [HSO4] using ethanol as solvent. The clusters crystallize in triclinic with a space group P1. The core contains 4 iron atoms, which are coplanar connected by the central μ3-O bridge, μ2-O and μ3-O bridge of SO4 groups. Protonated imidazoliums are the counter cations for the balance of charges of the core. Variable temperature magnetic susceptibility measurements of the Fe4 sulfate clusters reveal weak antiferromagnetic exchange interactions between the metal centers. In contrast, the reaction of FeCl3 under the similar experimental conditions didn't produce the similar cluster structure, whereas iron-DMSO complex[FeCl2(DMSO)4] [EtSO4]·DMSO (3) was obtained.
2017, 33(12): 2193-2200
doi: 10.11862/CJIC.2017.275
Abstract:
Uniformly rod-shaped CuFe4Ox catalysts were controllably fabricated through a liquid-phase precipitation method. The phase structure, morphology and reduction properties of the catalyst were characterized by in-situ powder X-ray diffraction (XRD), high resolution transmission electron microscope (HRTEM) and temperature-programmed reduction (TPR). Cu0/Fe3O4-nanorod obtained from the reduction of rod-shaped CuFe4Ox structure and the surface phase composition of Cu0/Fe3O4 was detailed studied by in-situ X-ray photoelectron spectroscopy (XPS). CuFe4Ox composites with rod-shape were prepared by an aqueous precipitation method that means after stirring time at 120℃ for 3 h, Na2CO3 solution was added until pH value equal to 9. In this case, the most uniform CuFe4Ox composites with rod-shape were obtained. Cu0/Fe3O4-nanorod catalyst presents higher activity and stability for the dehydrogenation of isoamylic alcohol than Cu/Fe3O4-nanoparticles, due to Cu0 nanoparticles supported on the rod-shaped Fe3O4 exhibits higher structure stability.
Uniformly rod-shaped CuFe4Ox catalysts were controllably fabricated through a liquid-phase precipitation method. The phase structure, morphology and reduction properties of the catalyst were characterized by in-situ powder X-ray diffraction (XRD), high resolution transmission electron microscope (HRTEM) and temperature-programmed reduction (TPR). Cu0/Fe3O4-nanorod obtained from the reduction of rod-shaped CuFe4Ox structure and the surface phase composition of Cu0/Fe3O4 was detailed studied by in-situ X-ray photoelectron spectroscopy (XPS). CuFe4Ox composites with rod-shape were prepared by an aqueous precipitation method that means after stirring time at 120℃ for 3 h, Na2CO3 solution was added until pH value equal to 9. In this case, the most uniform CuFe4Ox composites with rod-shape were obtained. Cu0/Fe3O4-nanorod catalyst presents higher activity and stability for the dehydrogenation of isoamylic alcohol than Cu/Fe3O4-nanoparticles, due to Cu0 nanoparticles supported on the rod-shaped Fe3O4 exhibits higher structure stability.
2017, 33(12): 2271-2277
doi: 10.11862/CJIC.2017.264
Abstract:
CdSe nanotube and nanowire arrays have been fabricated in the porous anodic aluminum oxide template (AAO) by electrodeposition method. The morphology, structure and composition of the materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) respectively. The photocatalytic activities of the materials were investigated by UV-vis absorption spectroscopy. The results show that CdSe nanotube and nanowire arrays can be fabricated by controlling the deposited charge. The CdSe nanomaterials are composed of mixed phase nature of hexagonal and cubic phase. It can be observed that the crystal transformation from the cubic phase to the hexagonal phase after the annealing process at 350℃. Meanwhile, the open-circuit potential differences (Voc) of the annealed CdSe nanomaterials have significantly increased, and photocurrent density at 0 V (versus SCE) has also improved, indicating that the annealed nanomaterials show better photoelectrochemical properties. Furthermore, the absorption edge and band gap of CdSe nanowires are about 710 nm and 1.85 eV respectively, CdSe nanotube arrays exhibit a better photoelectrochemical performance and a higher activity than nanowires for photodegrading rhodamine B with the degradation efficiency of 53.93% under a Xe lamp irradiation for 7 h. In addition, the growth mechanism of CdSe nanomaterials in the pore walls of AAO template has also been discussed.
CdSe nanotube and nanowire arrays have been fabricated in the porous anodic aluminum oxide template (AAO) by electrodeposition method. The morphology, structure and composition of the materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) respectively. The photocatalytic activities of the materials were investigated by UV-vis absorption spectroscopy. The results show that CdSe nanotube and nanowire arrays can be fabricated by controlling the deposited charge. The CdSe nanomaterials are composed of mixed phase nature of hexagonal and cubic phase. It can be observed that the crystal transformation from the cubic phase to the hexagonal phase after the annealing process at 350℃. Meanwhile, the open-circuit potential differences (Voc) of the annealed CdSe nanomaterials have significantly increased, and photocurrent density at 0 V (versus SCE) has also improved, indicating that the annealed nanomaterials show better photoelectrochemical properties. Furthermore, the absorption edge and band gap of CdSe nanowires are about 710 nm and 1.85 eV respectively, CdSe nanotube arrays exhibit a better photoelectrochemical performance and a higher activity than nanowires for photodegrading rhodamine B with the degradation efficiency of 53.93% under a Xe lamp irradiation for 7 h. In addition, the growth mechanism of CdSe nanomaterials in the pore walls of AAO template has also been discussed.
2017, 33(12): 2278-2286
doi: 10.11862/CJIC.2017.279
Abstract:
Three new coordination complexes[Mg(DCBA)2(H2O)4]·3(4, 4'-bipy) (1), [Ca(DCBA)(H2O)4]·DCBA·H2O (2) and[Cd(DCBA)2(H2O)2]·2H2O (3) were synthesized by evaporation methods using 2, 4-dichlorophenylacetic acid (DCBA), 4, 4'-bipyridine (4, 4'-bipy) to react with MgSO4, CaCl2 and Cd(NO3)2, respectively. The complexes were characterized by elemental analysis, FT-IR, thermogravimetrie analysis (TGA) and X-ray single-crystal structure analysis, and fluorescence properties of the complex 3 have been studied. As a result, complexes 1, 2 and 3 are zero-dimensional structure. Among others, there are O-H…O, O-H…N, C-H…O, C-H…Cl, C-H…π and O-H…O, C-H…Cl hydrogen bonds contributing 3D supramolecular structure of 1 and 2, 3, respectively.
Three new coordination complexes[Mg(DCBA)2(H2O)4]·3(4, 4'-bipy) (1), [Ca(DCBA)(H2O)4]·DCBA·H2O (2) and[Cd(DCBA)2(H2O)2]·2H2O (3) were synthesized by evaporation methods using 2, 4-dichlorophenylacetic acid (DCBA), 4, 4'-bipyridine (4, 4'-bipy) to react with MgSO4, CaCl2 and Cd(NO3)2, respectively. The complexes were characterized by elemental analysis, FT-IR, thermogravimetrie analysis (TGA) and X-ray single-crystal structure analysis, and fluorescence properties of the complex 3 have been studied. As a result, complexes 1, 2 and 3 are zero-dimensional structure. Among others, there are O-H…O, O-H…N, C-H…O, C-H…Cl, C-H…π and O-H…O, C-H…Cl hydrogen bonds contributing 3D supramolecular structure of 1 and 2, 3, respectively.
2017, 33(12): 2287-2295
doi: 10.11862/CJIC.2017.273
Abstract:
Two new mononuclear copper(Ⅱ) complexes, [CuL(NO3)2] (1) and[CuL(OAc)(H2O)]ClO4 (2), with dpa-based ligand (L=4-methyl-N, N-bis(pyridin-2-ylmethyl)aniline) have been synthesized and characterized by various physico-chemical techniques. The crystal structure of complex 1 displays a distorted pentagonal bipyramidal geometry, and the geometry around copper center of 2 can be described as a distorted octahedron. Interaction of the complexes with CT-DNA has been explored by using absorption and emission spectral methods, and the result suggests that the binding strength of the two complexes with DNA is a medium intercalative mode. The concentration-dependent and time-dependent DNA cleavage activity and the mechanism of DNA cleavage have been investigated, which suggest the DNA cleavage efficiencies of both complexes exhibit remarkable enhancement in the presence of external revulsants, and oxidative mechanism has been demonstrated via the pathway involving both hydroxyl radicals (·OH) and singlet oxygen (1O2) as ROS. The in vitro cytotoxic activity of the complexes has been examined by MTT on three cell lines such as HeLa, HepG-2 and SGC-7901.
Two new mononuclear copper(Ⅱ) complexes, [CuL(NO3)2] (1) and[CuL(OAc)(H2O)]ClO4 (2), with dpa-based ligand (L=4-methyl-N, N-bis(pyridin-2-ylmethyl)aniline) have been synthesized and characterized by various physico-chemical techniques. The crystal structure of complex 1 displays a distorted pentagonal bipyramidal geometry, and the geometry around copper center of 2 can be described as a distorted octahedron. Interaction of the complexes with CT-DNA has been explored by using absorption and emission spectral methods, and the result suggests that the binding strength of the two complexes with DNA is a medium intercalative mode. The concentration-dependent and time-dependent DNA cleavage activity and the mechanism of DNA cleavage have been investigated, which suggest the DNA cleavage efficiencies of both complexes exhibit remarkable enhancement in the presence of external revulsants, and oxidative mechanism has been demonstrated via the pathway involving both hydroxyl radicals (·OH) and singlet oxygen (1O2) as ROS. The in vitro cytotoxic activity of the complexes has been examined by MTT on three cell lines such as HeLa, HepG-2 and SGC-7901.
2017, 33(12): 2296-2302
doi: 10.11862/CJIC.2017.278
Abstract:
A composite of MgH2-MoS2-PP (PP=pyrolyzed polyaniline, wMoS2=wPP=8.33%) was prepared by ball-milling. In comparison to pure MgH2, the onset decomposition temperature of the composite decreases from 650 to 550 K and the hydrogen desorption content increases from 0.38% to 2.36% (w/w, the same below) at 573 K within 75 min. The composite can absorb 2.45% H2 within 40 min, which is 2.13 times higher than that of the MgH2 at 423 K. The apparent activation energy of the composite is 101.83 kJ·mol-1, decreasing by 28.81 kJ·mol-1 compared to MgH2. The reason of superior hydrogen storage performance of the PP-MoS2-MgH2 composite is found to be that PP can effectively decrease the size of Mg particles and enhance the catalytic efficiency of MoS2 in the desorption-resorption cycling.
A composite of MgH2-MoS2-PP (PP=pyrolyzed polyaniline, wMoS2=wPP=8.33%) was prepared by ball-milling. In comparison to pure MgH2, the onset decomposition temperature of the composite decreases from 650 to 550 K and the hydrogen desorption content increases from 0.38% to 2.36% (w/w, the same below) at 573 K within 75 min. The composite can absorb 2.45% H2 within 40 min, which is 2.13 times higher than that of the MgH2 at 423 K. The apparent activation energy of the composite is 101.83 kJ·mol-1, decreasing by 28.81 kJ·mol-1 compared to MgH2. The reason of superior hydrogen storage performance of the PP-MoS2-MgH2 composite is found to be that PP can effectively decrease the size of Mg particles and enhance the catalytic efficiency of MoS2 in the desorption-resorption cycling.
2017, 33(12): 2303-2310
doi: 10.11862/CJIC.2017.222
Abstract:
Two transition metal complexes:Cu2(pca)2(H2O)6·2H2O (1) and Mn(Hpca)2(phen)·3H2O (2) (H2pca=pyrazole-3-carboxylic acid; phen=phenanthroline) have been prepared based on pyrazole-3-carboxylic acid and structurally characterized. The single crystal X-ray diffraction analysis reveals that complex 1 crystallizes in the monoclinic system P21/n space group and the binuclear copper center in 1 and mononuclear Mn(Ⅱ) center in 2 possess the distorted octahedral geometry. The three dimensional 3D framework of 1 and 2 are formed by the intermolecular O-H…O, N-H…O hydrogen bonding interactions. Importantly, complex 1 exhibits excellent heterogeneous catalytic performance (Conversion:up to 97.4%, Selectivity:up to 98.9%) in the catalytic conversion of CO2 to cyclic carbonate.
Two transition metal complexes:Cu2(pca)2(H2O)6·2H2O (1) and Mn(Hpca)2(phen)·3H2O (2) (H2pca=pyrazole-3-carboxylic acid; phen=phenanthroline) have been prepared based on pyrazole-3-carboxylic acid and structurally characterized. The single crystal X-ray diffraction analysis reveals that complex 1 crystallizes in the monoclinic system P21/n space group and the binuclear copper center in 1 and mononuclear Mn(Ⅱ) center in 2 possess the distorted octahedral geometry. The three dimensional 3D framework of 1 and 2 are formed by the intermolecular O-H…O, N-H…O hydrogen bonding interactions. Importantly, complex 1 exhibits excellent heterogeneous catalytic performance (Conversion:up to 97.4%, Selectivity:up to 98.9%) in the catalytic conversion of CO2 to cyclic carbonate.
2017, 33(12): 2311-2321
doi: 10.11862/CJIC.2017.200
Abstract:
Iron(Ⅱ) triazole (SCO1) and iron(Ⅱ) 4-amino-triazole (SCO2) spin-crossover (SCO) nanomaterials were assembled in the channel and on the surface of anodic aluminum oxide (AAO) templates simultaneously by a facile sequential multistep assembly method. The obtained SCO1-1D+2D and SCO2-1D+2D nanomaterials have been characterized by SEM, FT-IR, PXRD, and Raman spectra. SEM images show that spherical SCO NPs growing in the channel of AAO templates aggregate with time going on, and assemble as 1D nanostructure. While those growing on the surface of AAO substrates assemble as uniform and dense 2D SCO film. It is interesting that both SCO-1D+2D nanostructures present a special two-step spin-crossover behaviour with hysteresis loops (SCO1-1D+2D:Tc1↑=319 K, Tc1↓=313 K, Tc2↑=381 K, Tc2↓=340 K; SCO2-1D+2D:Tc1↑=181 K, Tc1↓=155 K, Tc2↑=246 K, Tc2↓=233 K). The magnetic measuring of SCO-1D and SCO-2D indicates that the two-step SCO behaviour results from the different assembly morphologies of SCO. The first step spin transition at lower temperature is ascribed to the properties of 2D SCO films growing on the surface of AAO templates, while the transition in the second step at higher temperature can be attributed to the 1D SCO confined assembly growing in the channel of AAO membranes.
Iron(Ⅱ) triazole (SCO1) and iron(Ⅱ) 4-amino-triazole (SCO2) spin-crossover (SCO) nanomaterials were assembled in the channel and on the surface of anodic aluminum oxide (AAO) templates simultaneously by a facile sequential multistep assembly method. The obtained SCO1-1D+2D and SCO2-1D+2D nanomaterials have been characterized by SEM, FT-IR, PXRD, and Raman spectra. SEM images show that spherical SCO NPs growing in the channel of AAO templates aggregate with time going on, and assemble as 1D nanostructure. While those growing on the surface of AAO substrates assemble as uniform and dense 2D SCO film. It is interesting that both SCO-1D+2D nanostructures present a special two-step spin-crossover behaviour with hysteresis loops (SCO1-1D+2D:Tc1↑=319 K, Tc1↓=313 K, Tc2↑=381 K, Tc2↓=340 K; SCO2-1D+2D:Tc1↑=181 K, Tc1↓=155 K, Tc2↑=246 K, Tc2↓=233 K). The magnetic measuring of SCO-1D and SCO-2D indicates that the two-step SCO behaviour results from the different assembly morphologies of SCO. The first step spin transition at lower temperature is ascribed to the properties of 2D SCO films growing on the surface of AAO templates, while the transition in the second step at higher temperature can be attributed to the 1D SCO confined assembly growing in the channel of AAO membranes.
2017, 33(12): 2322-2328
doi: 10.11862/CJIC.2017.229
Abstract:
One-dimensional manganese(Ⅱ) and two-dimensional copper(Ⅱ) coordination polymers, namely[Mn(μ3-2, 4-H2bpta)(4, 4'-bipy)2]n (1) and {[Cu(μ4-3, 5-bpta)0.5(2, 2'-bipy)(H2O)]·H2O}n (2), have been constructed hydro-thermally using 2, 4-H4bpta (2, 4-H4bpta=biphenyl-2, 2', 4, 4'-tetracarboxylic acid), 3, 5-H4bpta (3, 5-H4bpta=biphenyl-3, 3', 5, 5'-tetracarboxylic acid), 4, 4'-bipy (4, 4'-bipy=4, 4'-bipyridine) or 2, 2'-bipy (2, 2'-bipy=2, 2'-bipyridine), and manganese or copper chlorides. Single-crystal X-ray diffraction analyses reveal that the two complexes crystallize in the monoclinic system, space group P21/c or C2/c. In complex 1, the carboxylate groups of 2, 4-H2bpta2- ligands bridge alternately neighboring Mn(Ⅱ) ions to form a double-helix chain. Adjacent chains are assembled to a 2D supramolecular network through O-H…N hydrogen bond. Complex 2 shows a 2D sheet. Magnetic studies for complex 1 demonstrate a ferromagnetic coupling between the adjacent Mn(Ⅱ) centers.
One-dimensional manganese(Ⅱ) and two-dimensional copper(Ⅱ) coordination polymers, namely[Mn(μ3-2, 4-H2bpta)(4, 4'-bipy)2]n (1) and {[Cu(μ4-3, 5-bpta)0.5(2, 2'-bipy)(H2O)]·H2O}n (2), have been constructed hydro-thermally using 2, 4-H4bpta (2, 4-H4bpta=biphenyl-2, 2', 4, 4'-tetracarboxylic acid), 3, 5-H4bpta (3, 5-H4bpta=biphenyl-3, 3', 5, 5'-tetracarboxylic acid), 4, 4'-bipy (4, 4'-bipy=4, 4'-bipyridine) or 2, 2'-bipy (2, 2'-bipy=2, 2'-bipyridine), and manganese or copper chlorides. Single-crystal X-ray diffraction analyses reveal that the two complexes crystallize in the monoclinic system, space group P21/c or C2/c. In complex 1, the carboxylate groups of 2, 4-H2bpta2- ligands bridge alternately neighboring Mn(Ⅱ) ions to form a double-helix chain. Adjacent chains are assembled to a 2D supramolecular network through O-H…N hydrogen bond. Complex 2 shows a 2D sheet. Magnetic studies for complex 1 demonstrate a ferromagnetic coupling between the adjacent Mn(Ⅱ) centers.
2017, 33(12): 2329-2337
doi: 10.11862/CJIC.2017.274
Abstract:
Two metallocene catalysts and one late transition metal catalyst were immobilized respectively on the surface of spherical α-Ti(HPO4)2 treated with methylaluminoxane. All the supported catalysts have higher activities than those of their referenced silica supported catalysts in olefin polymerizations. The activities of α-Ti(HPO4)2 supported metallocene catalysts in ethylene and propylene polymerizations are up to 6.8×107 gPE·(molZr·h)-1 and 5.0×107 gPP·(molZr·h)-1. These supported catalysts can produce narrow molecular weight distribution polyolefins (Mw/Mn < 2.3) and polypropylene with high isotactic index (96.5%). The late transition metal catalyst supported on α-Ti(HPO4)2 has relatively less activity (8.3×106 gPE·(molFe·h)-1) in ethylene polymerization but the produced polyethylene has a very broad Mw/Mn (>19). The particles of the produced polyolefins are mainly ball-shaped which replicate the morphology of spherical α-Ti(HPO4)2.
Two metallocene catalysts and one late transition metal catalyst were immobilized respectively on the surface of spherical α-Ti(HPO4)2 treated with methylaluminoxane. All the supported catalysts have higher activities than those of their referenced silica supported catalysts in olefin polymerizations. The activities of α-Ti(HPO4)2 supported metallocene catalysts in ethylene and propylene polymerizations are up to 6.8×107 gPE·(molZr·h)-1 and 5.0×107 gPP·(molZr·h)-1. These supported catalysts can produce narrow molecular weight distribution polyolefins (Mw/Mn < 2.3) and polypropylene with high isotactic index (96.5%). The late transition metal catalyst supported on α-Ti(HPO4)2 has relatively less activity (8.3×106 gPE·(molFe·h)-1) in ethylene polymerization but the produced polyethylene has a very broad Mw/Mn (>19). The particles of the produced polyolefins are mainly ball-shaped which replicate the morphology of spherical α-Ti(HPO4)2.
2017, 33(12): 2338-2344
doi: 10.11862/CJIC.2017.262
Abstract:
Two binuclear copper(Ⅱ) complexes were prepared with ligand 1, 4, 7-tribenzyl-1, 4, 7-triazacyclononane (Bn3tacn):[Cu2(Bn3tacn)2(m-bdc)(CH3CN)3(H2O)2]ClO4 (1) and[Cu2(Bn3tacn)2(OH)2](ClO4)2 (2). The copper(Ⅱ) ion in complex 1 is bridged by the m-benedicarboxylic acid (m-bdc) adopting bis(bidentate/monodentate) coordination type and is bridged by the μ-OH in complex 2. Complexes 1 and 2 crystalize in the monoclinic system, space group P21/c and C2/c, respectively. IR, UV-Vis, element analysis, binding with DNA properties of the complex 1 and cyclic voltammogram of complex 2 have been studied.
Two binuclear copper(Ⅱ) complexes were prepared with ligand 1, 4, 7-tribenzyl-1, 4, 7-triazacyclononane (Bn3tacn):[Cu2(Bn3tacn)2(m-bdc)(CH3CN)3(H2O)2]ClO4 (1) and[Cu2(Bn3tacn)2(OH)2](ClO4)2 (2). The copper(Ⅱ) ion in complex 1 is bridged by the m-benedicarboxylic acid (m-bdc) adopting bis(bidentate/monodentate) coordination type and is bridged by the μ-OH in complex 2. Complexes 1 and 2 crystalize in the monoclinic system, space group P21/c and C2/c, respectively. IR, UV-Vis, element analysis, binding with DNA properties of the complex 1 and cyclic voltammogram of complex 2 have been studied.
2017, 33(12): 2345-2350
doi: 10.11862/CJIC.2017.261
Abstract:
Two new metal complexes of {[CoL(H2O)4]SO4·H2O}n (1) and [Cu(hfac)2L2] (2, hfac=hexafluoroa-cetylacetonate) based on 3, 5-bis(3-pyridyl)-4-amino-1, 2, 4-triazole (L) have been synthesized and characterized by infrared spectrum (IR), elemental analysis (EA), and X-ray single crystal diffraction. For 1, ligand L adopts a cis-conformation and acts as a bidentate spacer to bind Co(Ⅱ) centers to form a one-dimensional (1D) sinusoidal chain. These sinusoidal chains are linked with each other and give a three-dimensional (3D) framework through O-H…O and O-H…N hydrogen bonds of neighboring chains. H2O guest molecules and SO42- anions are bound on the framework through hydrogen bonding system. For 2, while the ligand L also adopts a cis-conformaation, it acts as a monodentate spacer to bind Cu(Ⅱ) centers to form a discrete mononuclear complex, which is also linked into a three-dimensional (3D) framework through hydrogen bonds.
Two new metal complexes of {[CoL(H2O)4]SO4·H2O}n (1) and [Cu(hfac)2L2] (2, hfac=hexafluoroa-cetylacetonate) based on 3, 5-bis(3-pyridyl)-4-amino-1, 2, 4-triazole (L) have been synthesized and characterized by infrared spectrum (IR), elemental analysis (EA), and X-ray single crystal diffraction. For 1, ligand L adopts a cis-conformation and acts as a bidentate spacer to bind Co(Ⅱ) centers to form a one-dimensional (1D) sinusoidal chain. These sinusoidal chains are linked with each other and give a three-dimensional (3D) framework through O-H…O and O-H…N hydrogen bonds of neighboring chains. H2O guest molecules and SO42- anions are bound on the framework through hydrogen bonding system. For 2, while the ligand L also adopts a cis-conformaation, it acts as a monodentate spacer to bind Cu(Ⅱ) centers to form a discrete mononuclear complex, which is also linked into a three-dimensional (3D) framework through hydrogen bonds.
2017, 33(12): 2351-2356
doi: 10.11862/CJIC.2017.260
Abstract:
A new kind of ZSM-5 surface modification method was developed by using a large organic molecule Grignard reagent (3, 5-dimethyl phenylmagnesium bromide). Their shape selective catalytic properties were studied by ethylbenzene (EB) disproportionation reaction test. The pore structure and surface acid properties were also investigated to understand the shape selectivity enhancement mechanism. Most of the MgO was deposited on external surface due to the big molecule size of 3, 5-dimethyl phenylmagnesium bromide. The elimination of external surface acid sites by Grignard reagent is the main reason of its high p-diethylbenzene (p-DEB) selectivity in EB disproportionation reaction. The results of probe molecule adsorption kinetics experiment indicate that this modification method does not change the pore size of ZSM-5.
A new kind of ZSM-5 surface modification method was developed by using a large organic molecule Grignard reagent (3, 5-dimethyl phenylmagnesium bromide). Their shape selective catalytic properties were studied by ethylbenzene (EB) disproportionation reaction test. The pore structure and surface acid properties were also investigated to understand the shape selectivity enhancement mechanism. Most of the MgO was deposited on external surface due to the big molecule size of 3, 5-dimethyl phenylmagnesium bromide. The elimination of external surface acid sites by Grignard reagent is the main reason of its high p-diethylbenzene (p-DEB) selectivity in EB disproportionation reaction. The results of probe molecule adsorption kinetics experiment indicate that this modification method does not change the pore size of ZSM-5.
2017, 33(12): 2201-2207
doi: 10.11862/CJIC.2017.271
Abstract:
1, 3, 5, 7-tetramethyl-3a, 4a-diaza-s-indacene p-toluenesulfonate(T1) was synthesized by solvent-free method using 2, 4-dimethylpyrrole, triethyl orthoformate and p-toluenesulfonic acid. 1, 3, 5, 7-tetramethyl-4, 4-difluoro-4-bora-3a, 4a-diaza-s-indacene(F1) was synthesized by solvent-free method using T1, boron trifluoride diethyl ether and triethylamine. The structures of compounds have been characterized by 1H NMR and single-crystal X-ray diffraction. The results show that T1 belongs to monoclinic system, space group P21/c with a=0.777 3(3) nm, b=1.518 5(5)nm, c=1.612 2(5) nm, β=91.923(12)°, V=1.901 9(11) nm3, Z=4 and that F1 belongs to monoclinic system, space group P21/n with a=0.775 02(1) nm, b=1.444 20(3) nm, c=1.174 35(2) nm, β=107.779 5(9)°, V=1.251 65(4) nm3, Z=4. In four different solvent, the UV-Vis spectrum of T1, the UV-Vis and steady-state fluorescence spectra of F1 were determined. The possible derived way of T1 and F1 were investigated by the density functional calculation and the front orbital theory.
1, 3, 5, 7-tetramethyl-3a, 4a-diaza-s-indacene p-toluenesulfonate(T1) was synthesized by solvent-free method using 2, 4-dimethylpyrrole, triethyl orthoformate and p-toluenesulfonic acid. 1, 3, 5, 7-tetramethyl-4, 4-difluoro-4-bora-3a, 4a-diaza-s-indacene(F1) was synthesized by solvent-free method using T1, boron trifluoride diethyl ether and triethylamine. The structures of compounds have been characterized by 1H NMR and single-crystal X-ray diffraction. The results show that T1 belongs to monoclinic system, space group P21/c with a=0.777 3(3) nm, b=1.518 5(5)nm, c=1.612 2(5) nm, β=91.923(12)°, V=1.901 9(11) nm3, Z=4 and that F1 belongs to monoclinic system, space group P21/n with a=0.775 02(1) nm, b=1.444 20(3) nm, c=1.174 35(2) nm, β=107.779 5(9)°, V=1.251 65(4) nm3, Z=4. In four different solvent, the UV-Vis spectrum of T1, the UV-Vis and steady-state fluorescence spectra of F1 were determined. The possible derived way of T1 and F1 were investigated by the density functional calculation and the front orbital theory.
2017, 33(12): 2208-2214
doi: 10.11862/CJIC.2017.267
Abstract:
Nano CuFe2O4-rGO composites were successfully prepared by solvothermal method. The phase structure, morphology and capacitance of the sample were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrochemical workstation, respectively. The results indicated that the CuFe2O4 nanoparticles were uniformly dispersed in the graphene nanosheets, and the CuFe2O4-20%rGO composite shown the best electrochemical performance. When the current density is 1 A·g-1 the specific capacitance of the CuFe2O4-20% rGO composite was 1 952.5 F·g-1, and shown an excellent cycling stability along with 86.17% specific capacitane retained after 1 000 cycle tests.
Nano CuFe2O4-rGO composites were successfully prepared by solvothermal method. The phase structure, morphology and capacitance of the sample were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrochemical workstation, respectively. The results indicated that the CuFe2O4 nanoparticles were uniformly dispersed in the graphene nanosheets, and the CuFe2O4-20%rGO composite shown the best electrochemical performance. When the current density is 1 A·g-1 the specific capacitance of the CuFe2O4-20% rGO composite was 1 952.5 F·g-1, and shown an excellent cycling stability along with 86.17% specific capacitane retained after 1 000 cycle tests.
2017, 33(12): 2215-2224
doi: 10.11862/CJIC.2017.266
Abstract:
Pure goethite (Goe) and Al-doped goethite (Goe-Al0.1, Goe-Al0.2 and Goe-Al0.4) were prepared under hydrothermal conditions, and the surface properties and fluoride adsorption characteristics of the samples were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen physical adsorption, potentiometric titrations and batch adsorption experiments. The results show that both the crystallinity of the samples and the length of rod nanoparticles decrease with increasing the Al contents. The micropore surface areas, pore volumes and surface fractal dimension D values of the samples follow the order of Goe ＜ Goe-Al0.1 ＜ Goe-Al0.2 ＜ Goe-Al0.4, and the pore size distributions of the four samples show the opposite order. The points of zero charge (PZC) of Goe, Goe-Al0.1, Goe-Al0.2 and Goe-Al0.4 appear around 8.2, 8.3, 8.5 and 8.7, respectively. At pH=5.0, the surface charges of the four samples are 0.66, 0.83, 1.03 and 1.19 mmol·g-1, respectively. The adsorption kinetic data for fluoride by the samples were well fitted using the pseudo-second-order kinetic model, suggesting that chemisorption is important in the adsorption process. One-site Langmuir model is suitable to describe the isotherm adsorption data (R2=0.967~0.981). Compared to the correlation coefficients (R2) fitted using one-site Langmuir model, the R2 fitted using two-site Langmuir model are higher (R2=0.982~0.995), but the R2 fitted using Freundlich model are lower (R2=0.877~0.912). At pH=5.0, Langmuir adsorption capacities (qmax) of Goe, Goe-Al0.1, Goe-Al0.2 and Goe-Al0.4 are 8.83, 10.24, 11.72 and 12.86 mg·g-1, respectively. This indicates that the adsorption capacity for fluoride onto Al-doped goethite is higher than that onto Goe.
Pure goethite (Goe) and Al-doped goethite (Goe-Al0.1, Goe-Al0.2 and Goe-Al0.4) were prepared under hydrothermal conditions, and the surface properties and fluoride adsorption characteristics of the samples were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen physical adsorption, potentiometric titrations and batch adsorption experiments. The results show that both the crystallinity of the samples and the length of rod nanoparticles decrease with increasing the Al contents. The micropore surface areas, pore volumes and surface fractal dimension D values of the samples follow the order of Goe ＜ Goe-Al0.1 ＜ Goe-Al0.2 ＜ Goe-Al0.4, and the pore size distributions of the four samples show the opposite order. The points of zero charge (PZC) of Goe, Goe-Al0.1, Goe-Al0.2 and Goe-Al0.4 appear around 8.2, 8.3, 8.5 and 8.7, respectively. At pH=5.0, the surface charges of the four samples are 0.66, 0.83, 1.03 and 1.19 mmol·g-1, respectively. The adsorption kinetic data for fluoride by the samples were well fitted using the pseudo-second-order kinetic model, suggesting that chemisorption is important in the adsorption process. One-site Langmuir model is suitable to describe the isotherm adsorption data (R2=0.967~0.981). Compared to the correlation coefficients (R2) fitted using one-site Langmuir model, the R2 fitted using two-site Langmuir model are higher (R2=0.982~0.995), but the R2 fitted using Freundlich model are lower (R2=0.877~0.912). At pH=5.0, Langmuir adsorption capacities (qmax) of Goe, Goe-Al0.1, Goe-Al0.2 and Goe-Al0.4 are 8.83, 10.24, 11.72 and 12.86 mg·g-1, respectively. This indicates that the adsorption capacity for fluoride onto Al-doped goethite is higher than that onto Goe.
2017, 33(12): 2225-2232
doi: 10.11862/CJIC.2017.270
Abstract:
The Bi/TiO2 composite nanofibers were prepared by locating the Bi nanoparticles through solvothermal process on the electrospun TiO2 in the presence of EDTA, which acted as chelating and adsorbent agent. The phase, morphology and optical properties were characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope, energy dispersive spectroscopy, UV-Vis diffuse reflection spectrum and photoluminescence. The results indicate that EDTA plays an important role in the preparation of the composite nanofibers, which means the size and the density of Bi nanoparticles locating at the surface of the nanofibers could be well controlled by changing the concentration of EDTA. The catalysts exhibit the highest photocatalytic efficiency when the content of Bi is 65%. The RhB was degraded for 96.40% under visible light irradiation for 180 min, and the degradation efficiency remained over 91% after 5 runs, which suggests that the photocatalysts got well photocatalytic activity and stability.
The Bi/TiO2 composite nanofibers were prepared by locating the Bi nanoparticles through solvothermal process on the electrospun TiO2 in the presence of EDTA, which acted as chelating and adsorbent agent. The phase, morphology and optical properties were characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope, energy dispersive spectroscopy, UV-Vis diffuse reflection spectrum and photoluminescence. The results indicate that EDTA plays an important role in the preparation of the composite nanofibers, which means the size and the density of Bi nanoparticles locating at the surface of the nanofibers could be well controlled by changing the concentration of EDTA. The catalysts exhibit the highest photocatalytic efficiency when the content of Bi is 65%. The RhB was degraded for 96.40% under visible light irradiation for 180 min, and the degradation efficiency remained over 91% after 5 runs, which suggests that the photocatalysts got well photocatalytic activity and stability.
2017, 33(12): 2233-2240
doi: 10.11862/CJIC.2017.268
Abstract:
In this work, CuZnAl hydrotalcite-like compounds were prepared by a co-precipitation method, and the obtained hydrotalcite-like compounds were loaded on the surface of activated carbon fibers (ACFs). The composites consisting of CuZnAl phase and ACFs were prepared by calcination of the hydrotalcite-like compounds with ACFs and then reduction. The composites were characterized by XRD, FTIR and N2 adsorption-desorption analyses, and catalytic activity of the composites was evaluated for synthesis of higher alcohols form syngas. The results suggest that the active components of the composites are well dispersed on the surface of the ACFs. The particle size of the catalyst decreases and its specific surface area increase with addition of ACFs. The electrical conductivity of ACFs improves electron transfer during alcohol synthesis, which promotes the synthesis reaction and thus increases CO conversion (the highest conversion of 47%). In addition, ACFs enhance dispersity of ZnO and therefore promote formation of metal-oxide interface between Cu and ZnO. This facilities synthesis of higher alcohols, and therefore the selectivity for the alcohols with more than one carbon atoms reached up to 39%.
In this work, CuZnAl hydrotalcite-like compounds were prepared by a co-precipitation method, and the obtained hydrotalcite-like compounds were loaded on the surface of activated carbon fibers (ACFs). The composites consisting of CuZnAl phase and ACFs were prepared by calcination of the hydrotalcite-like compounds with ACFs and then reduction. The composites were characterized by XRD, FTIR and N2 adsorption-desorption analyses, and catalytic activity of the composites was evaluated for synthesis of higher alcohols form syngas. The results suggest that the active components of the composites are well dispersed on the surface of the ACFs. The particle size of the catalyst decreases and its specific surface area increase with addition of ACFs. The electrical conductivity of ACFs improves electron transfer during alcohol synthesis, which promotes the synthesis reaction and thus increases CO conversion (the highest conversion of 47%). In addition, ACFs enhance dispersity of ZnO and therefore promote formation of metal-oxide interface between Cu and ZnO. This facilities synthesis of higher alcohols, and therefore the selectivity for the alcohols with more than one carbon atoms reached up to 39%.
2017, 33(12): 2241-2246
doi: 10.11862/CJIC.2017.276
Abstract:
Pure BiFeO3 nanoparticles (A) and BiFeO3/Bi25FeO40/Fe2O3 composite nanoparticles (B) were synthsized through solvothermal porcess by using polyamidoamine (PAMAM) dendrimer as stabilizer. The structure, mophology and properties of the samples were characterized by XRD, HRTEM, UV-Vis and SQUID. These particles are uniform balls with the diameter less than 10 nm. Methylene blue can be effectively degradated by these nanoparticles, and the recovery of photocatalysts are 74.6% (A) and 90.2%(B) in the magnetic field generated by magnets. Both the photocatalytic activity and saturation magnetization of BiFeO3/Bi25FeO40/Fe2O3 composite nanopartcles are higher than that of pure BiFeO3 nanopartcles. These differences are derived from the more phases, the heterogeneous structure of the phase boundary, and the higher absorption ability of visible light of BiFeO3/Bi25FeO40/Fe2O3 composite nanopartcles.
Pure BiFeO3 nanoparticles (A) and BiFeO3/Bi25FeO40/Fe2O3 composite nanoparticles (B) were synthsized through solvothermal porcess by using polyamidoamine (PAMAM) dendrimer as stabilizer. The structure, mophology and properties of the samples were characterized by XRD, HRTEM, UV-Vis and SQUID. These particles are uniform balls with the diameter less than 10 nm. Methylene blue can be effectively degradated by these nanoparticles, and the recovery of photocatalysts are 74.6% (A) and 90.2%(B) in the magnetic field generated by magnets. Both the photocatalytic activity and saturation magnetization of BiFeO3/Bi25FeO40/Fe2O3 composite nanopartcles are higher than that of pure BiFeO3 nanopartcles. These differences are derived from the more phases, the heterogeneous structure of the phase boundary, and the higher absorption ability of visible light of BiFeO3/Bi25FeO40/Fe2O3 composite nanopartcles.
2017, 33(12): 2247-2254
doi: 10.11862/CJIC.2017.277
Abstract:
Ag@AgI/Ni thin films plasmonic photocatalyst were prepared by electrochemical method. The surface morphology, phase structure, optical characteristics and band structure of the thin film were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS), respectively. Its photocatalytic properties and stability were evaluated with rhodamine B(RhB) as a model compound under the simulated solar irradiation. Using a method of adding active species scavenger to the solution, mechanism of photocatalytic degradation of the films was explored. The Ag@AgI/Ni thin films prepared under the optimized preparation conditions are composed of AgI micron-sized particles coated with Ag nanocrystals, which have a significant surface plasmon resonance (SPR) effect. The thin film exhibits a maximum photocatalytic activity and a superior photocatalytic stability to decompose RhB. The photodegradation rate of the Ag@AgI/Ni thin films under the simulated solar irradiation 60 min (i.e., 81.1%) is 1.35 times greater than that of AgI/Ni thin film, and 1.61 times greater than that of P25 TiO2/ITO thin film. The photocatalytic activity almost keeps unchanged after five recycled experiments. The improvement in photocatalytic activity for Ag@AgI/Ni thin film can be mainly attributed to the activation of nano Ag particles on the film for photocathode reaction with a significant SPR effects. In addition, the photodegradation mechanism of the films for RhB under the simulated solar irradiation was also discussed.
Ag@AgI/Ni thin films plasmonic photocatalyst were prepared by electrochemical method. The surface morphology, phase structure, optical characteristics and band structure of the thin film were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS), respectively. Its photocatalytic properties and stability were evaluated with rhodamine B(RhB) as a model compound under the simulated solar irradiation. Using a method of adding active species scavenger to the solution, mechanism of photocatalytic degradation of the films was explored. The Ag@AgI/Ni thin films prepared under the optimized preparation conditions are composed of AgI micron-sized particles coated with Ag nanocrystals, which have a significant surface plasmon resonance (SPR) effect. The thin film exhibits a maximum photocatalytic activity and a superior photocatalytic stability to decompose RhB. The photodegradation rate of the Ag@AgI/Ni thin films under the simulated solar irradiation 60 min (i.e., 81.1%) is 1.35 times greater than that of AgI/Ni thin film, and 1.61 times greater than that of P25 TiO2/ITO thin film. The photocatalytic activity almost keeps unchanged after five recycled experiments. The improvement in photocatalytic activity for Ag@AgI/Ni thin film can be mainly attributed to the activation of nano Ag particles on the film for photocathode reaction with a significant SPR effects. In addition, the photodegradation mechanism of the films for RhB under the simulated solar irradiation was also discussed.
2017, 33(12): 2255-2261
doi: 10.11862/CJIC.2017.218
Abstract:
Ultrathin nanosheets of g-C3N4 were constructed through adjusting the manner of thermal polymerization. The results indicate that the thickness of these uniformly distributed sheets arrange from 0.2 to 0.4 nm and the surface area of them can reach up to 99 m2·g-1. The photocatalytic performance illustrates that they are not only well photocatalysts for water splitting, but also for antibacterial in the area of microorganism. Moreover, with the polymerized temperature increasing, the number of the layers decreased and the photocatalytic performance improved.
Ultrathin nanosheets of g-C3N4 were constructed through adjusting the manner of thermal polymerization. The results indicate that the thickness of these uniformly distributed sheets arrange from 0.2 to 0.4 nm and the surface area of them can reach up to 99 m2·g-1. The photocatalytic performance illustrates that they are not only well photocatalysts for water splitting, but also for antibacterial in the area of microorganism. Moreover, with the polymerized temperature increasing, the number of the layers decreased and the photocatalytic performance improved.
2017, 33(12): 2262-2270
doi: 10.11862/CJIC.2017.216
Abstract:
Silicon nanoparticles (Si NPs) have been prepared by DC arc-discharge plasma, which were pretreated by 4-aminobenzoic acid (ABA) and further in situ coated by the conductive polyaniline (PANi) on its surface, thus the core/shell type polyaniline-silicon nanoparticles (PANi-Si NPs) composite was fabricated. Analysis results by means of Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), transmission electron microscopy (TEM) and X-ray diffraction (XRD) indicate that ABA and Si NPs are connected by chemical bonds, and the aniline (ANi) group has been grafted onto the surface of Si NPs. The content of PANi in the composite particles is about 62%. As an anode material for Li-ion batteries, the existence of PANi coating layer can greatly improve the cycle stability of Si NPs-containing electrode. About 92.5% of the initial capacity can be maintained after 100 cycles at current density of 100 mA·g-1. The incorporation of PANi can make the active Si NPs surrounded by the conformal conductive coating, not only providing good electrical connection to Si NPs, but also accommodating huge volume change of silicon during the charge-discharge process to greatly enhance its cycling performance.
Silicon nanoparticles (Si NPs) have been prepared by DC arc-discharge plasma, which were pretreated by 4-aminobenzoic acid (ABA) and further in situ coated by the conductive polyaniline (PANi) on its surface, thus the core/shell type polyaniline-silicon nanoparticles (PANi-Si NPs) composite was fabricated. Analysis results by means of Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), transmission electron microscopy (TEM) and X-ray diffraction (XRD) indicate that ABA and Si NPs are connected by chemical bonds, and the aniline (ANi) group has been grafted onto the surface of Si NPs. The content of PANi in the composite particles is about 62%. As an anode material for Li-ion batteries, the existence of PANi coating layer can greatly improve the cycle stability of Si NPs-containing electrode. About 92.5% of the initial capacity can be maintained after 100 cycles at current density of 100 mA·g-1. The incorporation of PANi can make the active Si NPs surrounded by the conformal conductive coating, not only providing good electrical connection to Si NPs, but also accommodating huge volume change of silicon during the charge-discharge process to greatly enhance its cycling performance.
