Monophasic mullite gel with composition 3Al2O3·2SiO2 was prepared by the sol-gel method using aluminium nitrate nonahydrate, aluminium-tri-isopropoxide, and tetraethylorthosili-cate as reagents. Gels with differe...Monophasic mullite gel with composition 3Al2O3·2SiO2 was prepared by the sol-gel method using aluminium nitrate nonahydrate, aluminium-tri-isopropoxide, and tetraethylorthosili-cate as reagents. Gels with different drying control chemical additives(DCCAs) and polyvinylpyrrolidone(PVP) as spinning assistant were dried at several temperatures. The influences of temperature, DCCAs and PVP in the drying process were investigated. N,N-dimethylformamide(DMF) was the optimum DCCA at 70℃ in the drying process. PVP decreased the solvent volatilization speed and prevented gel crack to a certain extent. FTIR results revealed that free water, ethanol, and isopropanol were completely removed by the drying procedure.展开更多
A novel phthalocyanine, 2,9（10）,16（17）,23（24）-tetra（4-benzoyl）phenoxyphthalocyanine, and its complexes with Zn（Ⅱ）, Cu（Ⅱ）, Co（Ⅱ）, and Ni（Ⅱ） have been synthesized and characterized by a combination o...A novel phthalocyanine, 2,9（10）,16（17）,23（24）-tetra（4-benzoyl）phenoxyphthalocyanine, and its complexes with Zn（Ⅱ）, Cu（Ⅱ）, Co（Ⅱ）, and Ni（Ⅱ） have been synthesized and characterized by a combination of elemental analysis, IR, IH NMR, UV-vis spectroscopy and mass spectrometry. All of the materials are very soluble in common organic solvents such as dichloro- methane, chloroform, tetrahydrofuran, N,N-dimethylformamide and dimethyl sulfoxide. The Q band wavelengths of the com- plexes decrease in the order： Zn 〉 Cu 〉 Ni 〉 Co. Redox processes were observed at -1.06, -0.74, 0.51 and 0.98 V for the free phthalocyanine, at -0.72 and 1.04 V for the Co（Ⅱ） complex, at -1.24, -0.77, -0.24, 0.61 and 0,91 V for the Cu（Ⅱ） complex, and at -0.74 and 1.20 V for the Ni（Ⅱ） complex. The cyclic voltammograms of the phthalocyanine ring of the four species are similar, with reduction and oxidation couples each involving a one-electron transfer process.展开更多
Reduced graphene oxide thin films were fabricated on quartz by spray coating method using a stable dispersion of reduced graphene oxide in N,N-Dimethylformamide.The dispersion was produced by chemical reduction of gra...Reduced graphene oxide thin films were fabricated on quartz by spray coating method using a stable dispersion of reduced graphene oxide in N,N-Dimethylformamide.The dispersion was produced by chemical reduction of graphene oxide,and the film thickness was controlled with the amount of spray volume.AFM measurements revealed that the thin films have near-atomically flat surface.The chemical and structural parameters of the samples were analyzed by Raman and XPS studies.It was found that the thin films show electrical conductivity with good optical transparency in the visible to near infrared region.The sheet resistance of the films can be significantly reduced by annealing in vacuum and reach 58 k?with a light transmittance of 68.69%at 550 nm.The conductive transparent properties of the reduced graphene oxide thin films would be useful to develop flexible electronics.展开更多
文摘Monophasic mullite gel with composition 3Al2O3·2SiO2 was prepared by the sol-gel method using aluminium nitrate nonahydrate, aluminium-tri-isopropoxide, and tetraethylorthosili-cate as reagents. Gels with different drying control chemical additives(DCCAs) and polyvinylpyrrolidone(PVP) as spinning assistant were dried at several temperatures. The influences of temperature, DCCAs and PVP in the drying process were investigated. N,N-dimethylformamide(DMF) was the optimum DCCA at 70℃ in the drying process. PVP decreased the solvent volatilization speed and prevented gel crack to a certain extent. FTIR results revealed that free water, ethanol, and isopropanol were completely removed by the drying procedure.
基金supported by the Application Foundation of the Science and Technology Office of Jilin Province (20080901)the Fundamental Research Funds for the Central Universities (09SSXT030)
文摘A novel phthalocyanine, 2,9（10）,16（17）,23（24）-tetra（4-benzoyl）phenoxyphthalocyanine, and its complexes with Zn（Ⅱ）, Cu（Ⅱ）, Co（Ⅱ）, and Ni（Ⅱ） have been synthesized and characterized by a combination of elemental analysis, IR, IH NMR, UV-vis spectroscopy and mass spectrometry. All of the materials are very soluble in common organic solvents such as dichloro- methane, chloroform, tetrahydrofuran, N,N-dimethylformamide and dimethyl sulfoxide. The Q band wavelengths of the com- plexes decrease in the order： Zn 〉 Cu 〉 Ni 〉 Co. Redox processes were observed at -1.06, -0.74, 0.51 and 0.98 V for the free phthalocyanine, at -0.72 and 1.04 V for the Co（Ⅱ） complex, at -1.24, -0.77, -0.24, 0.61 and 0,91 V for the Cu（Ⅱ） complex, and at -0.74 and 1.20 V for the Ni（Ⅱ） complex. The cyclic voltammograms of the phthalocyanine ring of the four species are similar, with reduction and oxidation couples each involving a one-electron transfer process.
基金supported by the National Key Basic Research Program of China(Grant No.2013CBA01703)the National Natural Science Foundation of China(Grant No.11174355)+2 种基金Teknologiateollisuus TT-100the European Union’s Seventh Framework Programme(Grant No.631610)Aalto University(Finland)
文摘Reduced graphene oxide thin films were fabricated on quartz by spray coating method using a stable dispersion of reduced graphene oxide in N,N-Dimethylformamide.The dispersion was produced by chemical reduction of graphene oxide,and the film thickness was controlled with the amount of spray volume.AFM measurements revealed that the thin films have near-atomically flat surface.The chemical and structural parameters of the samples were analyzed by Raman and XPS studies.It was found that the thin films show electrical conductivity with good optical transparency in the visible to near infrared region.The sheet resistance of the films can be significantly reduced by annealing in vacuum and reach 58 k?with a light transmittance of 68.69%at 550 nm.The conductive transparent properties of the reduced graphene oxide thin films would be useful to develop flexible electronics.
