A promising Co3O4/Cu O composite electrode material was successfully synthesized through a facile hydrothermal and calcination process. Effects of the surfactants hexadecyltrimethyl ammonium bromide(CTAB) and polyvi...A promising Co3O4/Cu O composite electrode material was successfully synthesized through a facile hydrothermal and calcination process. Effects of the surfactants hexadecyltrimethyl ammonium bromide(CTAB) and polyvinylpyrrolidone(PVP) on the morphology and electrochemical performance of the composite were investigated. Powder X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and nitrogen adsorption-desorption experiment were employed to characterize the microstructures and morphologies of the composite. Meanwhile, the electrochemical performances of the samples were studied using cyclic voltammetry(CV), galvanostatic charge-discharge test and electrochemical impedance spectroscopy(EIS). The results show that the porous Co3O4/Cu O-CTAB nanoplates own the best performance and exhibits a high specific capacitance of 398 F/g at 1 A/g with almost 100% capacitance retention over 2000 cycles, and it retains 90% of capacitance at 10 A/g.展开更多
At relatively high cellulose mass concentrations(8%,10%,and 12%),homogeneous acetylation of cellulose was carried out in an ionic liquid,1-allyl-3-methylimidazolium chloride(AmimCl).Without using any catalyst,cellulos...At relatively high cellulose mass concentrations(8%,10%,and 12%),homogeneous acetylation of cellulose was carried out in an ionic liquid,1-allyl-3-methylimidazolium chloride(AmimCl).Without using any catalyst,cellulose acetates(CAs)with the degree of substitution(DS)in a range from 0.4 to 3.0 were synthesized in one-step.The effects of reaction time,temperature and molar ratio of acetic anhydride/anhydroglucose unit(AGU) in cellulose on DS value of CAs were investigated.The synthesized CAs were characterized by means of FT-IR, NMR,and solubility,mechanical and thermal tests.After the acetylation,the used ionic liquid AmimCl was easily recycled and reused.This study shows the potential of the homogeneous acetylation of cellulose at relatively high concentrations in ionic liquids in future industrial applications.展开更多
In liquid-liquid systems, the substrates in the liquids are inaccessible to each other for the reaction. By adding a small quantity of phase transfer catalyst, the reaction can be made accessible and accelerated. The ...In liquid-liquid systems, the substrates in the liquids are inaccessible to each other for the reaction. By adding a small quantity of phase transfer catalyst, the reaction can be made accessible and accelerated. The present study involves the phase transfer catalyzed oxidation of 2-methyl-l-butanol by quaternary ammonium permanganate (tricaprylyl methyl ammonium permanganate). The attempt was to compare the kinetics under homogeneous and heterogeneous conditions. Experiments were conducted in a batch reactor to determine the kinetics under homogeneous conditions. A baffled horosilicate agitated reactor was used to find the enhancement factor and the kinetics under heterogeneous conditions. The rate constants determined under both homogeneous and heterogeneous conditions agreed very weU. The oxidation was found to be first order with respect to each of the reactants, quaternary ammonium permanganate and the alcohol, resulting in an overall second order rate expression. Aliquat336 (tricaprylylmethylammonium chloride) was found to be the best compared with the other catalysts tested (triethylbenzylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide and tetrabutylammonium hydrogen sulfate) and it gave an enhancement factor of 9.8.展开更多
The complex [Et4N][(Ph3P)2{CuS2WS2Fe} Br2] (1 ), C44, H50NBr2CuFeP2S4W, M4= 1246. 13, has been obtained by reaction of [Et4N]2[WS4] andFeBr2 with Cu (Ph3P )3I in MeCN/CH2Cl2. Crystal data for [Et4N][(Ph3P)2{CuS2WS2Fe)...The complex [Et4N][(Ph3P)2{CuS2WS2Fe} Br2] (1 ), C44, H50NBr2CuFeP2S4W, M4= 1246. 13, has been obtained by reaction of [Et4N]2[WS4] andFeBr2 with Cu (Ph3P )3I in MeCN/CH2Cl2. Crystal data for [Et4N][(Ph3P)2{CuS2WS2Fe) Br2] (1): triclinic, P1, Z = 2, a= 13. 495 (7), b = 15. 322 (5), c =12. 361 (4), a=105. 32(3), β=93. 19(4), γ=101. 35(4) and V=2401. 2 The bond lengths of W-Fe bond and the W-Cu distance are 2. 793(2) A and 2. 823(2), respectively. Three kind metal atoms of the title structure [Et4N][(Ph3P)2{CuS2WS2Fe}Br2] (1) are nearly distributed along a line, and along which three metalatoms (W, Cu, Fe) are approximately tetrahedral coordination.展开更多
基金Project(21471162)supported by the National Natural Science Foundation of ChinaProject(2014LY36)supported by the Science and Technology Project of Longyan CityChina
文摘A promising Co3O4/Cu O composite electrode material was successfully synthesized through a facile hydrothermal and calcination process. Effects of the surfactants hexadecyltrimethyl ammonium bromide(CTAB) and polyvinylpyrrolidone(PVP) on the morphology and electrochemical performance of the composite were investigated. Powder X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and nitrogen adsorption-desorption experiment were employed to characterize the microstructures and morphologies of the composite. Meanwhile, the electrochemical performances of the samples were studied using cyclic voltammetry(CV), galvanostatic charge-discharge test and electrochemical impedance spectroscopy(EIS). The results show that the porous Co3O4/Cu O-CTAB nanoplates own the best performance and exhibits a high specific capacitance of 398 F/g at 1 A/g with almost 100% capacitance retention over 2000 cycles, and it retains 90% of capacitance at 10 A/g.
基金Supported by the National Basic Research Program of China(2009CB219901)
文摘At relatively high cellulose mass concentrations(8%,10%,and 12%),homogeneous acetylation of cellulose was carried out in an ionic liquid,1-allyl-3-methylimidazolium chloride(AmimCl).Without using any catalyst,cellulose acetates(CAs)with the degree of substitution(DS)in a range from 0.4 to 3.0 were synthesized in one-step.The effects of reaction time,temperature and molar ratio of acetic anhydride/anhydroglucose unit(AGU) in cellulose on DS value of CAs were investigated.The synthesized CAs were characterized by means of FT-IR, NMR,and solubility,mechanical and thermal tests.After the acetylation,the used ionic liquid AmimCl was easily recycled and reused.This study shows the potential of the homogeneous acetylation of cellulose at relatively high concentrations in ionic liquids in future industrial applications.
文摘In liquid-liquid systems, the substrates in the liquids are inaccessible to each other for the reaction. By adding a small quantity of phase transfer catalyst, the reaction can be made accessible and accelerated. The present study involves the phase transfer catalyzed oxidation of 2-methyl-l-butanol by quaternary ammonium permanganate (tricaprylyl methyl ammonium permanganate). The attempt was to compare the kinetics under homogeneous and heterogeneous conditions. Experiments were conducted in a batch reactor to determine the kinetics under homogeneous conditions. A baffled horosilicate agitated reactor was used to find the enhancement factor and the kinetics under heterogeneous conditions. The rate constants determined under both homogeneous and heterogeneous conditions agreed very weU. The oxidation was found to be first order with respect to each of the reactants, quaternary ammonium permanganate and the alcohol, resulting in an overall second order rate expression. Aliquat336 (tricaprylylmethylammonium chloride) was found to be the best compared with the other catalysts tested (triethylbenzylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide and tetrabutylammonium hydrogen sulfate) and it gave an enhancement factor of 9.8.
文摘The complex [Et4N][(Ph3P)2{CuS2WS2Fe} Br2] (1 ), C44, H50NBr2CuFeP2S4W, M4= 1246. 13, has been obtained by reaction of [Et4N]2[WS4] andFeBr2 with Cu (Ph3P )3I in MeCN/CH2Cl2. Crystal data for [Et4N][(Ph3P)2{CuS2WS2Fe) Br2] (1): triclinic, P1, Z = 2, a= 13. 495 (7), b = 15. 322 (5), c =12. 361 (4), a=105. 32(3), β=93. 19(4), γ=101. 35(4) and V=2401. 2 The bond lengths of W-Fe bond and the W-Cu distance are 2. 793(2) A and 2. 823(2), respectively. Three kind metal atoms of the title structure [Et4N][(Ph3P)2{CuS2WS2Fe}Br2] (1) are nearly distributed along a line, and along which three metalatoms (W, Cu, Fe) are approximately tetrahedral coordination.