The silica opal templates were prepared from three silica colloids of different diameters of 230 nm, 500 nm and 1.5 mm by a filtration route. The large-scale stable opal template membranes after sintering the deposite...The silica opal templates were prepared from three silica colloids of different diameters of 230 nm, 500 nm and 1.5 mm by a filtration route. The large-scale stable opal template membranes after sintering the deposited SiO2 opal template can be successfully obtained by optimizing the pH value and NaCl concentration in silica colloidal solutions. The three-dimensionally ordered macroporous(3DOM) polyimide membranes without crack were fabricated by reproducing the structure of silica opal template. We prepared the pore-filling composite proton exchange membranes by filling the 3DOM structure with proton conducting organosilane sol. The result indicates that the composite membranes exhibit higher water uptake than pure filling organosilane gel. The proton conductivity increased with the increasing of pore cell in composite membranes.展开更多
The three-dimensional ordered macroporous CeO2:Yb,Er materials were prepared, and the influence of doping concentra- tion of Yb3+ or Er3+ ions on upconversion property was investigated. Green and red upconversion e...The three-dimensional ordered macroporous CeO2:Yb,Er materials were prepared, and the influence of doping concentra- tion of Yb3+ or Er3+ ions on upconversion property was investigated. Green and red upconversion emissions were observed under the excitation of 980 nm at room temperature. It was found that the ratio of red to green upconversion emission intensity increased with increasing of concentration of the Yb3+ or Er3+ ions in the three-dimensional ordered macroporous CeO2:Yb,Er materials. When the concentration of Yb3+ was 10 mol%, pure red upconversion emission was obtained. The varied mechanism of ratio of red to green upconversion emission intensity was discussed with the concentration of Yb3+ or Er3+ ions.展开更多
Three-dimensional (3D) ordered macroporous indium tin oxide (ITO) is pre- pared using a polymer colloidal crystal template that is formed by self-assembly of the monodisperse poly(methyl methacrylate) (PMMA) microsphe...Three-dimensional (3D) ordered macroporous indium tin oxide (ITO) is pre- pared using a polymer colloidal crystal template that is formed by self-assembly of the monodisperse poly(methyl methacrylate) (PMMA) microspheres. The morphologies and BET surface area of the macroporous material is examined by scanning electron micro- scope, transmission electron microscopy and N2 adsorption/desorption. Results indicate that the macroporous material has highly ordered arrays of the uniform pores replicated from the PMMA colloidal crystal template when the polymer colloidal crystal template is removed by calcinations at 500℃. The pore diameter (about 450 nm) of macroporous ITO slightly shrank to the PMMA microspheres. The BET surface area and pore volume of the macroporous material are 389 m2·g-1 and 0.36 cm3·g-1, respectively. Moreover, the macroporous ITO, containing 5 mol% Sn and after annealing under vacuum, shows the minimum resistivity of ρ = 8.2×10-3 Ω· cm. The conductive mechanism of macroporous ITO is discussed, and it is believed that the oxygen vacancies are the major factor for excellent electrical properties.展开更多
A novel glucose oxidase immobilized on three-dimensionally ordered macroporous (3DOM) material has been prepared by firstly preparation of hybrid 3DOM SiO2-NH2 materials using colloidal crystal method, and following...A novel glucose oxidase immobilized on three-dimensionally ordered macroporous (3DOM) material has been prepared by firstly preparation of hybrid 3DOM SiO2-NH2 materials using colloidal crystal method, and following covalent immobilization of glucose oxidase on the pore walls of the 3DOM materials. The materials were characterized by SEM, FTIR, DSC and BET techniques. SEM observation shows that the macropores are highly ordered and are interconnected by small windows. FTIR measurement shows that there are amino and organic groups in the pore walls. The surface area of the 3DOM SiO2-NH2 material is about 10.2 m2/g. The loaded amount of enzyme is increased with amino content in the materials. The immobilized enzyme has high activity, thermal stability and can be reused.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.20704004, 21074019)the Natural Science Foundation of Jilin Province, China(No.20101539)
文摘The silica opal templates were prepared from three silica colloids of different diameters of 230 nm, 500 nm and 1.5 mm by a filtration route. The large-scale stable opal template membranes after sintering the deposited SiO2 opal template can be successfully obtained by optimizing the pH value and NaCl concentration in silica colloidal solutions. The three-dimensionally ordered macroporous(3DOM) polyimide membranes without crack were fabricated by reproducing the structure of silica opal template. We prepared the pore-filling composite proton exchange membranes by filling the 3DOM structure with proton conducting organosilane sol. The result indicates that the composite membranes exhibit higher water uptake than pure filling organosilane gel. The proton conductivity increased with the increasing of pore cell in composite membranes.
基金supported by the Reserve Talents Project of Yunnan Province(2013HB068)Applied Basic Research Program of Yunnan Province(2014FB127)
文摘The three-dimensional ordered macroporous CeO2:Yb,Er materials were prepared, and the influence of doping concentra- tion of Yb3+ or Er3+ ions on upconversion property was investigated. Green and red upconversion emissions were observed under the excitation of 980 nm at room temperature. It was found that the ratio of red to green upconversion emission intensity increased with increasing of concentration of the Yb3+ or Er3+ ions in the three-dimensional ordered macroporous CeO2:Yb,Er materials. When the concentration of Yb3+ was 10 mol%, pure red upconversion emission was obtained. The varied mechanism of ratio of red to green upconversion emission intensity was discussed with the concentration of Yb3+ or Er3+ ions.
基金supported by the National Natural Science Foundation of China (21477146,21303263)the National High Technology Research and Development Program of China (863 Program,2015AA034603)+2 种基金Beijing Nova Program (Z141109001814072)the Specialized Research Fund for the Doctoral Program of Higher Education of China (20130007120011)the Science Foundation of China University of Petroleum-Beijing (YJRC-2013-13,2462013BJRC003)~~
基金supported by the National High Technology Research and Development Program of China(863 Program,2015AA034603)the National Natural Science Foundation of China(21477146,21673142 and 21303263)+2 种基金the Beijing Nova Program(Z141109001814072)the Specialized Research Fund for the Doctoral Program of Higher Education(20130007120011)the Science Foundation of China University of Petroleum-Beijing(YJRC-2013-13,2462013BJRC003)~~
文摘Three-dimensional (3D) ordered macroporous indium tin oxide (ITO) is pre- pared using a polymer colloidal crystal template that is formed by self-assembly of the monodisperse poly(methyl methacrylate) (PMMA) microspheres. The morphologies and BET surface area of the macroporous material is examined by scanning electron micro- scope, transmission electron microscopy and N2 adsorption/desorption. Results indicate that the macroporous material has highly ordered arrays of the uniform pores replicated from the PMMA colloidal crystal template when the polymer colloidal crystal template is removed by calcinations at 500℃. The pore diameter (about 450 nm) of macroporous ITO slightly shrank to the PMMA microspheres. The BET surface area and pore volume of the macroporous material are 389 m2·g-1 and 0.36 cm3·g-1, respectively. Moreover, the macroporous ITO, containing 5 mol% Sn and after annealing under vacuum, shows the minimum resistivity of ρ = 8.2×10-3 Ω· cm. The conductive mechanism of macroporous ITO is discussed, and it is believed that the oxygen vacancies are the major factor for excellent electrical properties.
文摘A novel glucose oxidase immobilized on three-dimensionally ordered macroporous (3DOM) material has been prepared by firstly preparation of hybrid 3DOM SiO2-NH2 materials using colloidal crystal method, and following covalent immobilization of glucose oxidase on the pore walls of the 3DOM materials. The materials were characterized by SEM, FTIR, DSC and BET techniques. SEM observation shows that the macropores are highly ordered and are interconnected by small windows. FTIR measurement shows that there are amino and organic groups in the pore walls. The surface area of the 3DOM SiO2-NH2 material is about 10.2 m2/g. The loaded amount of enzyme is increased with amino content in the materials. The immobilized enzyme has high activity, thermal stability and can be reused.