In this work, the highly ordered tungsten trioxide nanotube arrays have been synthesized by the combination of Sol-Gel chemical method and anodic aluminum oxide (AAO) templating method. The morphology and the chemical...In this work, the highly ordered tungsten trioxide nanotube arrays have been synthesized by the combination of Sol-Gel chemical method and anodic aluminum oxide (AAO) templating method. The morphology and the chemical composition of tungsten trioxide nanotubes arrays were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS) and X-ray diffraction (XRD). The results show that the wall thickness of the tungsten trioxide nanotubes arrays can be controlled by the immersion time. The growth mechanism of naotubes arrays is also discussed.展开更多
： The four heteropoly isomers K3H2[α-,β i-SiW11Fe(H2O)O39]· xH2O(β i=β 1,β 2,β 3)were prepared and Characterized by elementary analysis, IR and UV Spectroscopy. Its electrochemical behavior in aqueous solu...： The four heteropoly isomers K3H2[α-,β i-SiW11Fe(H2O)O39]· xH2O(β i=β 1,β 2,β 3)were prepared and Characterized by elementary analysis, IR and UV Spectroscopy. Its electrochemical behavior in aqueous solution has been discussed. The order of Polarographic half-wave potential E1/2 of heteropoly anions is as follows:β 2 >β 1 >β 3 >α . Its reduction process involves an one-electron reduction of Fe? and a pair of two-electron reduction of W? . Epolidation of maleic acid with H2O2 Catalyzed by heteropoly positional isomers was studied.β 3 isomers are the most active.展开更多
The novel amino acid containing polyoxometalate K 6[Cu(Ala) 2(H 2O) 2] 2[Cu 4(H 2O) 2\5(AsW 9O 34 ) 2]·16H 2O was synthesized from the reaction of K 10 [Cu 4(H 2O) 2(AsW 9O 34 ) 2]·20H 2O with β alanine. It...The novel amino acid containing polyoxometalate K 6[Cu(Ala) 2(H 2O) 2] 2[Cu 4(H 2O) 2\5(AsW 9O 34 ) 2]·16H 2O was synthesized from the reaction of K 10 [Cu 4(H 2O) 2(AsW 9O 34 ) 2]·20H 2O with β alanine. Its structure has been determined by single crystal X ray diffraction. It crystallizes in the triclinic space group P1 , with a =1.196 3(2) nm, b =1.536 5(3) nm, c =1.591 4(3) nm, α=93.97(3)°, β=110.88(3)°, γ=101.07(3)°, V =2.651 8(9) nm 3 and Z =1. Least squares refinement of the structure leads to R and R w factors of 0.067 3 and 0.162 8, respectively. An unusual structural feature of the compound is that the polyanion [Cu 4(H 2O) 2(AsW 9O 34 ) 2] 10- is linked with the amino acid complex of Cu 2+ by a μ oxygen atom.展开更多
synthesized with hydrazine oxalic acid and tungstic acid in different ratios and a series of tungsten oxides, O/W ratios from 2.90 to 2.30,were obtained by thermal decomposition from the precursors under nitrogen atmo...synthesized with hydrazine oxalic acid and tungstic acid in different ratios and a series of tungsten oxides, O/W ratios from 2.90 to 2.30,were obtained by thermal decomposition from the precursors under nitrogen atmosphere at 640～760℃. This kind of tungsten oxides were found to belong to mixed valence compounds which have some special electrical properties. The experimental result indicated that the electrical conductivity of this tungsten oxide has a close relation with its O/W ratio and reach the maximum at WO2.50. Seclecting WO2.50 as an example, its conductivity was measured at different temperatures from -197 ℃to -2.5 ℃and it was found that the mixed valence tungsten oxide as conductor belongs to the class of metal ones. Owing to their relatively high electrical conductivity and stability in air, mixed valence tungsten oxide shows some potential use in polymer products as additives.展开更多
文摘In this work, the highly ordered tungsten trioxide nanotube arrays have been synthesized by the combination of Sol-Gel chemical method and anodic aluminum oxide (AAO) templating method. The morphology and the chemical composition of tungsten trioxide nanotubes arrays were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS) and X-ray diffraction (XRD). The results show that the wall thickness of the tungsten trioxide nanotubes arrays can be controlled by the immersion time. The growth mechanism of naotubes arrays is also discussed.
文摘： The four heteropoly isomers K3H2[α-,β i-SiW11Fe(H2O)O39]· xH2O(β i=β 1,β 2,β 3)were prepared and Characterized by elementary analysis, IR and UV Spectroscopy. Its electrochemical behavior in aqueous solution has been discussed. The order of Polarographic half-wave potential E1/2 of heteropoly anions is as follows:β 2 >β 1 >β 3 >α . Its reduction process involves an one-electron reduction of Fe? and a pair of two-electron reduction of W? . Epolidation of maleic acid with H2O2 Catalyzed by heteropoly positional isomers was studied.β 3 isomers are the most active.
文摘The novel amino acid containing polyoxometalate K 6[Cu(Ala) 2(H 2O) 2] 2[Cu 4(H 2O) 2\5(AsW 9O 34 ) 2]·16H 2O was synthesized from the reaction of K 10 [Cu 4(H 2O) 2(AsW 9O 34 ) 2]·20H 2O with β alanine. Its structure has been determined by single crystal X ray diffraction. It crystallizes in the triclinic space group P1 , with a =1.196 3(2) nm, b =1.536 5(3) nm, c =1.591 4(3) nm, α=93.97(3)°, β=110.88(3)°, γ=101.07(3)°, V =2.651 8(9) nm 3 and Z =1. Least squares refinement of the structure leads to R and R w factors of 0.067 3 and 0.162 8, respectively. An unusual structural feature of the compound is that the polyanion [Cu 4(H 2O) 2(AsW 9O 34 ) 2] 10- is linked with the amino acid complex of Cu 2+ by a μ oxygen atom.
文摘synthesized with hydrazine oxalic acid and tungstic acid in different ratios and a series of tungsten oxides, O/W ratios from 2.90 to 2.30,were obtained by thermal decomposition from the precursors under nitrogen atmosphere at 640～760℃. This kind of tungsten oxides were found to belong to mixed valence compounds which have some special electrical properties. The experimental result indicated that the electrical conductivity of this tungsten oxide has a close relation with its O/W ratio and reach the maximum at WO2.50. Seclecting WO2.50 as an example, its conductivity was measured at different temperatures from -197 ℃to -2.5 ℃and it was found that the mixed valence tungsten oxide as conductor belongs to the class of metal ones. Owing to their relatively high electrical conductivity and stability in air, mixed valence tungsten oxide shows some potential use in polymer products as additives.
