Three-dimensionally ordered mesoporous Fe2O3(meso-Fe2O3) and its supported Au, Pd,and Au-Pd alloy(xA uP dy/meso-Fe2O3; x = 0.08–0.72 wt.%; Pd/Au molar ratio(y) = 1.48–1.85)photocatalysts have been prepared via...Three-dimensionally ordered mesoporous Fe2O3(meso-Fe2O3) and its supported Au, Pd,and Au-Pd alloy(xA uP dy/meso-Fe2O3; x = 0.08–0.72 wt.%; Pd/Au molar ratio(y) = 1.48–1.85)photocatalysts have been prepared via the KIT-6-templating and polyvinyl alcohol-protected reduction routes, respectively. Physical properties of the samples were characterized, and their photocatalytic activities were evaluated for the photocatalytic oxidation of acetone in the presence of a small amount of H2O2 under visible-light illumination. It was found that the meso-Fe2O3 was rhombohedral in crystal structure. The as-obtained samples displayed a high surface area of 111.0–140.8 m^2/g and a bandgap energy of 1.98–2.12 eV. The Au, Pd and/or Au–Pd alloy nanoparticles(NPs) with a size of 3–4 nm were uniformly dispersed on the surface of the meso-Fe2O3 support. The 0.72 wt.% AuP d1.48/meso-Fe2O3 sample performed the best in the presence of 0.06 mol/L H2O2 aqueous solution, showing a 100% acetone conversion within4 hr of visible-light illumination. It was concluded that the good performance of 0.72 wt.%AuPd(1.48)/meso-Fe2O3 for photocatalytic acetone oxidation was associated with its ordered mesoporous structure, high adsorbed oxygen species concentration, plasmonic resonance effect between AuPd(1.48) NPs and meso-Fe2O3, and effective separation of the photogenerated charge carriers. In addition, the introduction of H2O2 and the involvement of the photo-Fenton process also played important roles in enhancing the photocatalytic activity of 0.72 wt.%AuPd(1.48)/meso-Fe2O3.展开更多
Three-dimensionally ordered macro-porous (3DOM) Pt/TiO2 catalysts were prepared by template and impregnation methods, and the resultant samples were characterized by using TG-DTA, XRD, SEM, TEM, and TPR techniques. ...Three-dimensionally ordered macro-porous (3DOM) Pt/TiO2 catalysts were prepared by template and impregnation methods, and the resultant samples were characterized by using TG-DTA, XRD, SEM, TEM, and TPR techniques. The catalytic performance for water-gas shift (WGS) reaction was tested, and the influences of some conditions, such as reduction temperature of catalysts, the amount of Pt loadings and space velocity on catalytic performance were investigated. It was shown that Pt particles were homogeneously dispersed on 3DOM TiO2. The reduction of TiO2 surface was important for the catalytic performance. The activity test results showed that the 3DOM Pt/TiO2 catalysts exhibited very good catalytic performance for WGS reaction even at high space velocity, which was owing to the better mass transfer of 3DOM porous structure besides the high intrinsic activity of Pt/TiO2.展开更多
采用溶胶-凝胶结合煅烧后处理方法,以聚苯乙烯(PS)胶球和EO20PO70EO20(P123)作为双模板剂制备了三维有序大孔复合材料3DOM Ti O2-Zr O2.通过XRD、UV-Vis/DRS、XPS、SEM以及氮气吸附-脱附等测试手段对其组成、结构与表面形貌进行了表征....采用溶胶-凝胶结合煅烧后处理方法,以聚苯乙烯(PS)胶球和EO20PO70EO20(P123)作为双模板剂制备了三维有序大孔复合材料3DOM Ti O2-Zr O2.通过XRD、UV-Vis/DRS、XPS、SEM以及氮气吸附-脱附等测试手段对其组成、结构与表面形貌进行了表征.同时,研究了3DOM Ti O2-Zr O2在多模式光催化条件下对有机污染物的降解情况.结果表明,3DOM Ti O2-Zr O2复合材料呈现的开放通透、整齐有序的"蜂巢状"大孔结构不仅有利于有机污染物分子的输入与输出,而且其良好的晶型结构与较高的BET比表面积进一步增强了其在紫外光、微波辅助以及模拟日光光催化降解甲基橙中的活性.同时,该复合材料对多种类型结构的有机污染物均显示一定程度的降解.展开更多
由 Si O2 胶体颗粒的三维有序自组装可以得到面心立方三维结构 ,它具有折射率周期性变化的特点。它的制备涉及胶体化学、材料科学等学科的前沿领域。其自组装方法包括胶体颗粒的沉降自组装、胶体颗粒在物体限制下的自组装、胶体颗粒的...由 Si O2 胶体颗粒的三维有序自组装可以得到面心立方三维结构 ,它具有折射率周期性变化的特点。它的制备涉及胶体化学、材料科学等学科的前沿领域。其自组装方法包括胶体颗粒的沉降自组装、胶体颗粒在物体限制下的自组装、胶体颗粒的连续对流自组装和利用胶体颗粒表面电性质的自组装。本文对这些组装方法进行了介绍。展开更多
Three-dimensionally ordered(3DOM) macroporous phosphotungstic acid/SiO_2(HPW/SiO_2) materials were prepared by using colloidal crystal as templates and applied for oxidative desulfurization(ODS) of the model fue...Three-dimensionally ordered(3DOM) macroporous phosphotungstic acid/SiO_2(HPW/SiO_2) materials were prepared by using colloidal crystal as templates and applied for oxidative desulfurization(ODS) of the model fuel oil. The obtained HPW/SiO_2 materials were characterized through scanning electron microscopy, powder X-ray diffraction, N_2 sorption, and Fourier transform infrared spectroscopy. The results indicated that 3 DOM HPW/SiO_2 possessed hierarchical pore architectures which contained ordered macropores and disordered mesopores, with the Keggin type HPW embedded in the framework of pore structure. The removal rate of dibenzothiophene(DBT) could reach 100% under the optimum conditions, moreover. The performance was only slightly decreased for the regenerated catalyst after 7 cycles.展开更多
基金support by the National Natural Science Foundation of China (51076154)the National Key Technology R&D Program of the 12th Five‐Year Plan of China (2011BAD15B05)the Science & Technology Research Project of Guangdong Province (2010B010900047)~~
基金supported by the National Natural Science Foundation of China (No. 21377008)the National High Technology Research and Development Program of China ("863"Program)(No. 2015AA034603)the Foundation of the Creative Research Team Construction Promotion Project of Beijing Municipal Institutions
文摘Three-dimensionally ordered mesoporous Fe2O3(meso-Fe2O3) and its supported Au, Pd,and Au-Pd alloy(xA uP dy/meso-Fe2O3; x = 0.08–0.72 wt.%; Pd/Au molar ratio(y) = 1.48–1.85)photocatalysts have been prepared via the KIT-6-templating and polyvinyl alcohol-protected reduction routes, respectively. Physical properties of the samples were characterized, and their photocatalytic activities were evaluated for the photocatalytic oxidation of acetone in the presence of a small amount of H2O2 under visible-light illumination. It was found that the meso-Fe2O3 was rhombohedral in crystal structure. The as-obtained samples displayed a high surface area of 111.0–140.8 m^2/g and a bandgap energy of 1.98–2.12 eV. The Au, Pd and/or Au–Pd alloy nanoparticles(NPs) with a size of 3–4 nm were uniformly dispersed on the surface of the meso-Fe2O3 support. The 0.72 wt.% AuP d1.48/meso-Fe2O3 sample performed the best in the presence of 0.06 mol/L H2O2 aqueous solution, showing a 100% acetone conversion within4 hr of visible-light illumination. It was concluded that the good performance of 0.72 wt.%AuPd(1.48)/meso-Fe2O3 for photocatalytic acetone oxidation was associated with its ordered mesoporous structure, high adsorbed oxygen species concentration, plasmonic resonance effect between AuPd(1.48) NPs and meso-Fe2O3, and effective separation of the photogenerated charge carriers. In addition, the introduction of H2O2 and the involvement of the photo-Fenton process also played important roles in enhancing the photocatalytic activity of 0.72 wt.%AuPd(1.48)/meso-Fe2O3.
基金supported by the Ministry of Sciences and Technology of China(863 programs,No 2006AA05Z115 and 2007AA05Z104)
文摘Three-dimensionally ordered macro-porous (3DOM) Pt/TiO2 catalysts were prepared by template and impregnation methods, and the resultant samples were characterized by using TG-DTA, XRD, SEM, TEM, and TPR techniques. The catalytic performance for water-gas shift (WGS) reaction was tested, and the influences of some conditions, such as reduction temperature of catalysts, the amount of Pt loadings and space velocity on catalytic performance were investigated. It was shown that Pt particles were homogeneously dispersed on 3DOM TiO2. The reduction of TiO2 surface was important for the catalytic performance. The activity test results showed that the 3DOM Pt/TiO2 catalysts exhibited very good catalytic performance for WGS reaction even at high space velocity, which was owing to the better mass transfer of 3DOM porous structure besides the high intrinsic activity of Pt/TiO2.
文摘采用溶胶-凝胶结合煅烧后处理方法,以聚苯乙烯(PS)胶球和EO20PO70EO20(P123)作为双模板剂制备了三维有序大孔复合材料3DOM Ti O2-Zr O2.通过XRD、UV-Vis/DRS、XPS、SEM以及氮气吸附-脱附等测试手段对其组成、结构与表面形貌进行了表征.同时,研究了3DOM Ti O2-Zr O2在多模式光催化条件下对有机污染物的降解情况.结果表明,3DOM Ti O2-Zr O2复合材料呈现的开放通透、整齐有序的"蜂巢状"大孔结构不仅有利于有机污染物分子的输入与输出,而且其良好的晶型结构与较高的BET比表面积进一步增强了其在紫外光、微波辅助以及模拟日光光催化降解甲基橙中的活性.同时,该复合材料对多种类型结构的有机污染物均显示一定程度的降解.
文摘由 Si O2 胶体颗粒的三维有序自组装可以得到面心立方三维结构 ,它具有折射率周期性变化的特点。它的制备涉及胶体化学、材料科学等学科的前沿领域。其自组装方法包括胶体颗粒的沉降自组装、胶体颗粒在物体限制下的自组装、胶体颗粒的连续对流自组装和利用胶体颗粒表面电性质的自组装。本文对这些组装方法进行了介绍。
基金the National Nature Science Foundation of China(No.21476177)
文摘Three-dimensionally ordered(3DOM) macroporous phosphotungstic acid/SiO_2(HPW/SiO_2) materials were prepared by using colloidal crystal as templates and applied for oxidative desulfurization(ODS) of the model fuel oil. The obtained HPW/SiO_2 materials were characterized through scanning electron microscopy, powder X-ray diffraction, N_2 sorption, and Fourier transform infrared spectroscopy. The results indicated that 3 DOM HPW/SiO_2 possessed hierarchical pore architectures which contained ordered macropores and disordered mesopores, with the Keggin type HPW embedded in the framework of pore structure. The removal rate of dibenzothiophene(DBT) could reach 100% under the optimum conditions, moreover. The performance was only slightly decreased for the regenerated catalyst after 7 cycles.