A highly hierarchically ordered macroporous-mesoporous Ce0.4Zr0.602 solid solution with crystalline framework walls was directly and simply prepared using polystyrene （PS） microspheres and a block copolymer as dual ...A highly hierarchically ordered macroporous-mesoporous Ce0.4Zr0.602 solid solution with crystalline framework walls was directly and simply prepared using polystyrene （PS） microspheres and a block copolymer as dual templates. The PS microspheres and block copolymer were assembled into colloidal crystals and mesoscopic rod-like micelles as macroporous and mesoporous templates, respectively, by a one-step process. This process offers a facile method to prepare hierarchically ordered porous materials. Compared to commercial ceria, the macroporous-mesoporous Ce0.4Zr0.602 material significantly improved the ultraviolet resistance and mechanical performance of a polysulfide polymer. Because the ordered macroporous-mesoporous Ce0.4Zr0.602 can disperse uniformly in the polysulfide polymer based on the open macroporous structure for diffusion and mobility and mesoporous structure for high surface areas. Furthermore, these results show that better-performing polysulfide polymers can be achieved by adding hierarchically structured materials.展开更多
The performance of catalysts used in after-treatment systems is the key factor for the removal of diesel soot,which is an important component of atmosphericfine particle emissions.Herein,three-dimensionally ordered ma...The performance of catalysts used in after-treatment systems is the key factor for the removal of diesel soot,which is an important component of atmosphericfine particle emissions.Herein,three-dimensionally ordered macroporous–mesoporous Ti_(x)Si+(1-x)O_(2)(3DOM-m Ti_(x)Si+(1-x)O_(2))and its supported MnO_(x)catalysts doped with different alkali/alkaline-earth metals(AMnO_(x)/3 DOM-m Ti_(0.7)Si_(0.3)O_(2)(A:Li,Na,K,Ru,Cs,Mg,Ca,Sr,Ba))were prepared by mesoporous template(P123)-assisted colloidal crystal template(CCT)and incipient wetness impregnation methods,respectively.Physicochemical characterizations of the catalysts were performed using scanning electron microscopy,X-ray diffraction,N_(2)adsorption–desorption,H_(2)temperature-programmed reduction,O_(2)temperature-programmed desorption,NO temperature-programmed oxidation,and Raman spectroscopy techniques;then,we evaluated their catalytic performances for the removal of diesel soot particles.The results show that the 3DOM-m Ti_(0.7)Si_(0.3)O_(2)supports exhibited a well-defined 3DOM-m nanostructure,and AMnO_(x)nanoparticles with 10–50 nm were evenly dispersed on the inner walls of the uniform macropores.In addition,the as-prepared catalysts exhibited good catalytic performance for soot combustion.Among the prepared catalysts,CsMnO_(x)/3DOM-m Ti_(0.7)Si_(0.3)O_(2)had the highest catalytic activity for soot combustion,with T10,T50,and T90(the temperatures corresponding to soot conversion rates of 10%,50%,and 90%)values of 285,355,and 393℃,respectively.The high catalytic activity of the CsMnO_(x)/3 DOM-m Ti_(0.7)Si_(0.3)O_(2)catalysts was attributed to their excellent low-temperature reducibility and homogeneous macroporous–mesoporous structure,as well as to the synergistic effects between Cs and Mn species and between CsMnO_(x)and the Ti_(0.7)Si_(0.3)O_(2)support.展开更多
文摘A highly hierarchically ordered macroporous-mesoporous Ce0.4Zr0.602 solid solution with crystalline framework walls was directly and simply prepared using polystyrene （PS） microspheres and a block copolymer as dual templates. The PS microspheres and block copolymer were assembled into colloidal crystals and mesoscopic rod-like micelles as macroporous and mesoporous templates, respectively, by a one-step process. This process offers a facile method to prepare hierarchically ordered porous materials. Compared to commercial ceria, the macroporous-mesoporous Ce0.4Zr0.602 material significantly improved the ultraviolet resistance and mechanical performance of a polysulfide polymer. Because the ordered macroporous-mesoporous Ce0.4Zr0.602 can disperse uniformly in the polysulfide polymer based on the open macroporous structure for diffusion and mobility and mesoporous structure for high surface areas. Furthermore, these results show that better-performing polysulfide polymers can be achieved by adding hierarchically structured materials.
基金supported by Key Research and Development Program of Ministry of Science and Technology of the People’s Republic of China(MOST)(No.2017YFE0131200)for collaboration between China and PolandNational Nature Science Foundation of China(NSFC)(Nos.22072095,U1908204,21761162016)+3 种基金General Projects of Liaoning Province Natural Fund(No.2019-MS-284)National Engineering Laboratory for Mobile Source Emission Control Technology(No.NELMS2018A04)University level innovation team of Shenyang Normal University,Major Incubation Program of Shenyang Normal University(No.ZD201901)supported by the Research Grants Council(RGC)of Hong Kong through NSFC/RGC Joint Research Scheme(No.N_CUHK451/17)。
文摘The performance of catalysts used in after-treatment systems is the key factor for the removal of diesel soot,which is an important component of atmosphericfine particle emissions.Herein,three-dimensionally ordered macroporous–mesoporous Ti_(x)Si+(1-x)O_(2)(3DOM-m Ti_(x)Si+(1-x)O_(2))and its supported MnO_(x)catalysts doped with different alkali/alkaline-earth metals(AMnO_(x)/3 DOM-m Ti_(0.7)Si_(0.3)O_(2)(A:Li,Na,K,Ru,Cs,Mg,Ca,Sr,Ba))were prepared by mesoporous template(P123)-assisted colloidal crystal template(CCT)and incipient wetness impregnation methods,respectively.Physicochemical characterizations of the catalysts were performed using scanning electron microscopy,X-ray diffraction,N_(2)adsorption–desorption,H_(2)temperature-programmed reduction,O_(2)temperature-programmed desorption,NO temperature-programmed oxidation,and Raman spectroscopy techniques;then,we evaluated their catalytic performances for the removal of diesel soot particles.The results show that the 3DOM-m Ti_(0.7)Si_(0.3)O_(2)supports exhibited a well-defined 3DOM-m nanostructure,and AMnO_(x)nanoparticles with 10–50 nm were evenly dispersed on the inner walls of the uniform macropores.In addition,the as-prepared catalysts exhibited good catalytic performance for soot combustion.Among the prepared catalysts,CsMnO_(x)/3DOM-m Ti_(0.7)Si_(0.3)O_(2)had the highest catalytic activity for soot combustion,with T10,T50,and T90(the temperatures corresponding to soot conversion rates of 10%,50%,and 90%)values of 285,355,and 393℃,respectively.The high catalytic activity of the CsMnO_(x)/3 DOM-m Ti_(0.7)Si_(0.3)O_(2)catalysts was attributed to their excellent low-temperature reducibility and homogeneous macroporous–mesoporous structure,as well as to the synergistic effects between Cs and Mn species and between CsMnO_(x)and the Ti_(0.7)Si_(0.3)O_(2)support.
