Low-loaded Pd（0.05 wt.%）/Al2O3 catalysts modified by ceria were prepared by impregnation method.Gas phase hydrogenation of acrylonitrile to propionitrile was selected as probe reaction to study the effect of the lig...Low-loaded Pd（0.05 wt.%）/Al2O3 catalysts modified by ceria were prepared by impregnation method.Gas phase hydrogenation of acrylonitrile to propionitrile was selected as probe reaction to study the effect of the light rare earth element cerium on the cataltic activity and stability.Experimental results indicated that addition of a small mount of ceria improved the catalytic activity and stability greatly.The best content of ceria was 3 wt.%,and consecutive impregnation method was prior to co-impregnation method.展开更多
As a green and sustainable technology,heterogeneous photocatalysis using semiconductors has received much attention during the past decades because of its potential to address energy and environmental problems. Among ...As a green and sustainable technology,heterogeneous photocatalysis using semiconductors has received much attention during the past decades because of its potential to address energy and environmental problems. Among various semiconductors,TiO2 has been regarded as the best and most widely investigated photocatalyst in the past 10 years. Based on the fundamentals of photocatalysis and surface chemistry of TiO2 nanomaterials,we herein summarize and discuss the achievements in the different surface modification strategies employed to date such as surface doping and sensitization,construction of surface heterojunctions,loading of nano-sized co-catalysts,increase in the accessible surface areas,and usage of surface F effects and exposure of highly reactive facets. Especially,the interesting synergistic effects of these different surface modification strategies deserve more attention in the near future. Studying these important advances in photocatalysis fundamentals,and surface chemistry and modification may offer new opportunities for designing highly efficient TiO2-based and non-TiO2-based photocatalysts for solar fuel production,environmental remediation,organic photosynthesis,and other related fields such as solar cell device fabrication,thermal catalysis,and separation and purification.展开更多
With the merits of high energy density,environmental friendliness,and cost effectiveness,lithium-sulfur(Li-S)batteries are considered as one of the most promising next-generation electrochemical storage systems.Howeve...With the merits of high energy density,environmental friendliness,and cost effectiveness,lithium-sulfur(Li-S)batteries are considered as one of the most promising next-generation electrochemical storage systems.However,the notorious polysulfide shuttle effect,which results in low active material utilization and serious capacity fading,severely impedes the practical application of Li-S batteries.Utilizing various electrocatalysts to improve the polysulfide redox kinetics has recently emerged as a promising strategy to address the shuttle effect.Specially,the electronic structure of the electrocatalysts plays a decisive role in determining the catalytic activity to facilitate the polysulfide conversion.Therefore,reasonably modulating the electronic structure of electrocatalysts is of paramount significance for improving the electrochemical performance of Li-S batteries.Herein,a comprehensive overview of the fascinating strategies to tailor the electronic structure of electrocatalysts for Li-S batteries is presented,including but not limited to vacancy engineering,heteroatom doping,single atom doping,band regulation,alloying,and heterostructure engineering.The future perspectives and challenges are also proposed for designing high-efficient electrocatalysts to construct high-energy-density and long-lifetime Li-S batteries.展开更多
The consumption ofthermoset resins as building polymers is approximately over one million tone word wide. The thermoset resins are proven construction materials for the technical and highly demanding applications of t...The consumption ofthermoset resins as building polymers is approximately over one million tone word wide. The thermoset resins are proven construction materials for the technical and highly demanding applications of the transportation, electrical and building part industry. Heat stability, high thermal, low shrinkage, excellent mechanical properties are typical for their type of polymers. Above applications in addition to the mechanical properties also require good flame retardants of the materials. Undertaken activities refer to official draft, laws and legal recommendations in UE states. This paper presents positive effect of reduced flammability of thermoset resins （unsaturated polyester and epoxy resins） thanks to the use of nanocomposites containing multi-ingredient halogen-flee flame retardants which combine conventional phosphorus/nitrogen modifiers interacting with nanofillers （oMMT （organomodified montmorillonite）, EG （expandable graphite）, graphene, GO （graphene oxide）, nSi （nanosilica））.展开更多
文摘Low-loaded Pd（0.05 wt.%）/Al2O3 catalysts modified by ceria were prepared by impregnation method.Gas phase hydrogenation of acrylonitrile to propionitrile was selected as probe reaction to study the effect of the light rare earth element cerium on the cataltic activity and stability.Experimental results indicated that addition of a small mount of ceria improved the catalytic activity and stability greatly.The best content of ceria was 3 wt.%,and consecutive impregnation method was prior to co-impregnation method.
基金supported by the Industry and Research Collaborative Innovation Major Projects Of Guangzhou(201508020098)the National Natural Science Foundation of China(20906034+2 种基金21173088and 21207041)the State Key Laboratory of Advanced Technology for Material Synthesis and Processing,Wuhan University of Technology(2015-KF-7)~~
文摘As a green and sustainable technology,heterogeneous photocatalysis using semiconductors has received much attention during the past decades because of its potential to address energy and environmental problems. Among various semiconductors,TiO2 has been regarded as the best and most widely investigated photocatalyst in the past 10 years. Based on the fundamentals of photocatalysis and surface chemistry of TiO2 nanomaterials,we herein summarize and discuss the achievements in the different surface modification strategies employed to date such as surface doping and sensitization,construction of surface heterojunctions,loading of nano-sized co-catalysts,increase in the accessible surface areas,and usage of surface F effects and exposure of highly reactive facets. Especially,the interesting synergistic effects of these different surface modification strategies deserve more attention in the near future. Studying these important advances in photocatalysis fundamentals,and surface chemistry and modification may offer new opportunities for designing highly efficient TiO2-based and non-TiO2-based photocatalysts for solar fuel production,environmental remediation,organic photosynthesis,and other related fields such as solar cell device fabrication,thermal catalysis,and separation and purification.
文摘With the merits of high energy density,environmental friendliness,and cost effectiveness,lithium-sulfur(Li-S)batteries are considered as one of the most promising next-generation electrochemical storage systems.However,the notorious polysulfide shuttle effect,which results in low active material utilization and serious capacity fading,severely impedes the practical application of Li-S batteries.Utilizing various electrocatalysts to improve the polysulfide redox kinetics has recently emerged as a promising strategy to address the shuttle effect.Specially,the electronic structure of the electrocatalysts plays a decisive role in determining the catalytic activity to facilitate the polysulfide conversion.Therefore,reasonably modulating the electronic structure of electrocatalysts is of paramount significance for improving the electrochemical performance of Li-S batteries.Herein,a comprehensive overview of the fascinating strategies to tailor the electronic structure of electrocatalysts for Li-S batteries is presented,including but not limited to vacancy engineering,heteroatom doping,single atom doping,band regulation,alloying,and heterostructure engineering.The future perspectives and challenges are also proposed for designing high-efficient electrocatalysts to construct high-energy-density and long-lifetime Li-S batteries.
文摘The consumption ofthermoset resins as building polymers is approximately over one million tone word wide. The thermoset resins are proven construction materials for the technical and highly demanding applications of the transportation, electrical and building part industry. Heat stability, high thermal, low shrinkage, excellent mechanical properties are typical for their type of polymers. Above applications in addition to the mechanical properties also require good flame retardants of the materials. Undertaken activities refer to official draft, laws and legal recommendations in UE states. This paper presents positive effect of reduced flammability of thermoset resins （unsaturated polyester and epoxy resins） thanks to the use of nanocomposites containing multi-ingredient halogen-flee flame retardants which combine conventional phosphorus/nitrogen modifiers interacting with nanofillers （oMMT （organomodified montmorillonite）, EG （expandable graphite）, graphene, GO （graphene oxide）, nSi （nanosilica））.
