Six coordination compounds of Pt(Ⅱ)L_2 and Ir(Ⅲ)L_3 type(where L is PT^-, 3Me-PT^-or 4Me-PT^-)are reported here.Four coordination compounds of the latter two ligands have never been reported before,while PT^-'s ...Six coordination compounds of Pt(Ⅱ)L_2 and Ir(Ⅲ)L_3 type(where L is PT^-, 3Me-PT^-or 4Me-PT^-)are reported here.Four coordination compounds of the latter two ligands have never been reported before,while PT^-'s were synthesized with H_2PtCl_6 and(NH_4)_3IrCl_6 respectively,which were different from the methods of Davidson et al.~1 and Sterinbrech^2.They were characterized by elemental analysis, UV,IR,~1HNMR and molar conductance.Their structural formulas have been determined,and the mechanism of synthetic reaction has been discussed.展开更多
Porous α-Fe2O3 was synthesized by a simple hydrothermal treatment of FeC13 aqueous solution followed by a calcination process. In the synthesis of porous α-Fe2O3, no templates or pore-directing agents were used. The...Porous α-Fe2O3 was synthesized by a simple hydrothermal treatment of FeC13 aqueous solution followed by a calcination process. In the synthesis of porous α-Fe2O3, no templates or pore-directing agents were used. The as-prepared porous α-Fe2O3 was further employed as a support for loading Pt nanoparticles. The gas sensing performance of the obtained porous α-Fe2O3-supported Pt to VOCs was investigated. The sensor presented a high response and fast response-recovery characteristic to several VOCs including acetone, ether, methanol, ethanol, butanol and hexanol. Meanwhile, it exhibited a much higher response than the pure α-Fe2O3 at the operating temperature of 260 ℃. The enhanced sensing properties may be related to the unique porous structure of the α-Fe2O3 support and the promoting effect of active Pt nanoparticles for the sensing reactions.展开更多
Pt nanoparticles entrapped in ordered mesoporous CMK-3 carbons with p6mm symmetry were prepared using a facile impregnation method, and the resulting materials were characterized using X-ray diffraction spectroscopy, ...Pt nanoparticles entrapped in ordered mesoporous CMK-3 carbons with p6mm symmetry were prepared using a facile impregnation method, and the resulting materials were characterized using X-ray diffraction spectroscopy, N2 adsorption-desorption, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The Pt nanoparticles were highly dispersed in the CMK-3 with 43.7% dispersion. The Pt/CMK-3 catalyst was an effective catalyst for the liquid-phase hydrogenation of nitrobenzene and its derivatives under the experimental conditions studied here. The Pt/CMK-3 catalyst was more active than commercial Pt/C catalyst in most cases. A highest turnover frequency of 43.8 s-1 was measured when the Pt/CMK-3 catalyst was applied for the hydrogenation of 2-methyl-nitrobenzene in ethanol under optimal conditions. It is worthy of note that the Pt/CMK-3 catalyst could be recycled easily, and could be reused at least fourteen times without any loss in activity or selectivity for the hydrogenation of nitrobenzene in ethanol.展开更多
分别通过自组装法(AS)和浸渍法(WI)制备得到纳米催化剂Pt/γ-Al2O3-AS和Pt/γ-Al2O3-WI,并用于评价甲苯、异丙醇、丙酮、乙酸乙酯等易挥发性有机物(VOCs)的氧化性能.通过各种表征手段探究了催化剂形态、结构及表面性质与催化剂氧化活性...分别通过自组装法(AS)和浸渍法(WI)制备得到纳米催化剂Pt/γ-Al2O3-AS和Pt/γ-Al2O3-WI,并用于评价甲苯、异丙醇、丙酮、乙酸乙酯等易挥发性有机物(VOCs)的氧化性能.通过各种表征手段探究了催化剂形态、结构及表面性质与催化剂氧化活性的关系.结果表明,Pt/γ-Al2O3-AS在低温下即可实现VOCs的完全氧化.在气体浓度(体积分数)为1000×10-6,空速为18000 m L·g-1·h-1的条件下,甲苯、异丙醇、丙酮、乙酸乙酯被Pt/γ-Al2O3-AS催化剂完全氧化的温度分别为130、135、145、215°C,展现出了优异的氧化性能,且具有很好的稳定性.该催化剂较高的比表面积、较小的Pt纳米粒径、较好的Pt纳米颗粒分散度、更好的低温还原效果及丰富的表面羟基是具有较高催化活性的重要因素.展开更多
文摘Six coordination compounds of Pt(Ⅱ)L_2 and Ir(Ⅲ)L_3 type(where L is PT^-, 3Me-PT^-or 4Me-PT^-)are reported here.Four coordination compounds of the latter two ligands have never been reported before,while PT^-'s were synthesized with H_2PtCl_6 and(NH_4)_3IrCl_6 respectively,which were different from the methods of Davidson et al.~1 and Sterinbrech^2.They were characterized by elemental analysis, UV,IR,~1HNMR and molar conductance.Their structural formulas have been determined,and the mechanism of synthetic reaction has been discussed.
基金supported by the National Natural Science Foundation of China (No. 20871071)the Science and Technology Commission Foundation of Tianjin (Nos. 09JCYBJC03600 and 10JCYBJC03900)
文摘Porous α-Fe2O3 was synthesized by a simple hydrothermal treatment of FeC13 aqueous solution followed by a calcination process. In the synthesis of porous α-Fe2O3, no templates or pore-directing agents were used. The as-prepared porous α-Fe2O3 was further employed as a support for loading Pt nanoparticles. The gas sensing performance of the obtained porous α-Fe2O3-supported Pt to VOCs was investigated. The sensor presented a high response and fast response-recovery characteristic to several VOCs including acetone, ether, methanol, ethanol, butanol and hexanol. Meanwhile, it exhibited a much higher response than the pure α-Fe2O3 at the operating temperature of 260 ℃. The enhanced sensing properties may be related to the unique porous structure of the α-Fe2O3 support and the promoting effect of active Pt nanoparticles for the sensing reactions.
基金supported by the National Natural Science Foundation of China(21273076 and 21373089)the Open Research Fund of Top Key Discipline of Chemistry in Zhejiang Provincial Colleges and Key Laboratory of the Ministry of Education for Catalysis Materials(Zhejiang Normal University,ZJHX2013)Shanghai Leading Academic Discipline Project (B409)~~
文摘Pt nanoparticles entrapped in ordered mesoporous CMK-3 carbons with p6mm symmetry were prepared using a facile impregnation method, and the resulting materials were characterized using X-ray diffraction spectroscopy, N2 adsorption-desorption, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The Pt nanoparticles were highly dispersed in the CMK-3 with 43.7% dispersion. The Pt/CMK-3 catalyst was an effective catalyst for the liquid-phase hydrogenation of nitrobenzene and its derivatives under the experimental conditions studied here. The Pt/CMK-3 catalyst was more active than commercial Pt/C catalyst in most cases. A highest turnover frequency of 43.8 s-1 was measured when the Pt/CMK-3 catalyst was applied for the hydrogenation of 2-methyl-nitrobenzene in ethanol under optimal conditions. It is worthy of note that the Pt/CMK-3 catalyst could be recycled easily, and could be reused at least fourteen times without any loss in activity or selectivity for the hydrogenation of nitrobenzene in ethanol.
基金supported by the Key Innovation Team of Science&Technology in Zhejiang Province,China(2011R50017)National HighTechnology Research and Development Program of China(863)(2013AA065005)~~
文摘分别通过自组装法(AS)和浸渍法(WI)制备得到纳米催化剂Pt/γ-Al2O3-AS和Pt/γ-Al2O3-WI,并用于评价甲苯、异丙醇、丙酮、乙酸乙酯等易挥发性有机物(VOCs)的氧化性能.通过各种表征手段探究了催化剂形态、结构及表面性质与催化剂氧化活性的关系.结果表明,Pt/γ-Al2O3-AS在低温下即可实现VOCs的完全氧化.在气体浓度(体积分数)为1000×10-6,空速为18000 m L·g-1·h-1的条件下,甲苯、异丙醇、丙酮、乙酸乙酯被Pt/γ-Al2O3-AS催化剂完全氧化的温度分别为130、135、145、215°C,展现出了优异的氧化性能,且具有很好的稳定性.该催化剂较高的比表面积、较小的Pt纳米粒径、较好的Pt纳米颗粒分散度、更好的低温还原效果及丰富的表面羟基是具有较高催化活性的重要因素.