Hydroformylation could convert olefins and syngas(mixture of H_(2) and CO)into aldehydes with a great atomic efficiency.This transformation serves as one of the most prominent processes in modern chemical industry;as ...Hydroformylation could convert olefins and syngas(mixture of H_(2) and CO)into aldehydes with a great atomic efficiency.This transformation serves as one of the most prominent processes in modern chemical industry;as it provides over 10 million tons of aldehydes as feedstock for our daily essential products such as plasticizers;paints;solvents;and pharmaceuticals.展开更多
CONSPECTUS:Single-atom catalysts(SACs)represent a transformative advancement in heterogeneous catalysis,offering unparalleled opportunities for maximizing atomic efficiency and enhancing performance.SACs are character...CONSPECTUS:Single-atom catalysts(SACs)represent a transformative advancement in heterogeneous catalysis,offering unparalleled opportunities for maximizing atomic efficiency and enhancing performance.SACs are characterized by isolated metal atoms uniformly dispersed on suitable supports,ensuring each metal atom serves as an independent catalytic site.This dispersion mitigates metal atom aggregation,a common issue in conventional nanocatalysts,thus enabling superior activity,selectivity,and stability.Metal−organic frameworks(MOFs)have emerged as an ideal platform for SAC synthesis due to their structural diversity,tunable coordination environments,and high surface areas.MOFs provide well-defined coordination sites that facilitate the precise stabilization of single metal atoms,presenting significant advantages over traditional supports like metal oxides and metal materials.Carbonization of MOFs yields MOF-derived carbon materials that retain key structural characteristics while offering enhanced electrical conductivity and stability,making them suitable for various catalytic applications.Recent advances in the rational design and controlled synthesis of MOF-derived SACs have significantly improved their performance in electrocatalytic processes such as the oxygen reduction reaction(ORR)and carbon dioxide reduction reaction(CO_(2)RR).However,challenges remain,including maintaining structural integrity during high-temperature carbonization,enhancing mass and electron transport and ensuring the stability of isolated metal atoms under reaction conditions.To address these challenges,strategies such as using structure-directing agents to stabilize MOF frameworks,forming high-energy porous carbon networks,and optimizing support morphologies have been developed to maximize active site exposure and accessibility.On the other hand,the interplay between active metal sites and their coordination environments is crucial in determining the catalytic activity and selectivity of SACs.Advanced computational modeling,coupled with experimental validation,has provided insights into the electronic structure of SACs and the interactions between metal atoms and supports.These insights have enabled researchers to fine-tune local atomic coordination,leading to significant enhancements in performance.For instance,modifying the coordination environment of metal atoms optimizes the binding strength of reaction intermediates,thereby improving both activity and selectivity.This account highlights our group’s contributions to MOF-derived SACs,focusing on innovative design,functionalization,and synthesis approaches that enhance catalytic activity.Notable strategies include using structure-directing agents to maintain pore connectivity during carbonization,preserving high surface areas,and enhancing mass transport.We also discuss the design of high-energy MOFderived porous carbon networks that facilitate continuous electron transport and improve the interaction between active sites and reactants,ultimately boosting catalytic efficiency.Techniques such as electrospinning have also been employed to create hierarchical porous structures and one-dimensional nanofibers,enhancing mass transport and electron transfer.The rational design of SACs requires a comprehensive understanding of the microenvironment surrounding active sites,and by leveraging computational and experimental tools,researchers can precisely control these microenvironments to achieve desired outcomes.MOF-derived SACs hold substantial promise for energy conversion and chemical synthesis.Continued research is essential to optimize their design,improve scalability,and explore new applications,ultimately advancing sustainable catalysis.This account provides an overview of the latest advancements in MOF-derived SACs,highlighting their potential as next-generation electrocatalysts and their role in sustainable energy technologies.展开更多
We demonstrate the generation of non-classical photon pairs in a warm S-Rb atomic vapor （＇ell with no buffer gas or polarization preserving coatings via spontaneous four-wave mixing. We obtain the photon pairs with ...We demonstrate the generation of non-classical photon pairs in a warm S-Rb atomic vapor （＇ell with no buffer gas or polarization preserving coatings via spontaneous four-wave mixing. We obtain the photon pairs with a 1/e correlation time of 40 ns and the violation of Cauchy-Sehwartz inequality by a factor of 23 - 3. This provides a convenient and efficient method to generate photon pair sources based on an atomic ensemble.展开更多
基金supported from the National Key R&D Program(No.2023YFB4103100,and 2023YFB4103102)National Natural Science Foundation of China(No.22172186,22302221,and 22202229)+3 种基金Major science and technology project of Ordos(No.2022EEDSKJZDZX001)Inner Mongolia Key Research and Development Program(No.2023YFHH0009)Institute of Coal Chemistry,Chinese Academy of SciencesSynfuels China,Co.Ltd..
文摘Hydroformylation could convert olefins and syngas(mixture of H_(2) and CO)into aldehydes with a great atomic efficiency.This transformation serves as one of the most prominent processes in modern chemical industry;as it provides over 10 million tons of aldehydes as feedstock for our daily essential products such as plasticizers;paints;solvents;and pharmaceuticals.
基金financially supported by the National Natural Science Foundation of China(52332007Z).
文摘CONSPECTUS:Single-atom catalysts(SACs)represent a transformative advancement in heterogeneous catalysis,offering unparalleled opportunities for maximizing atomic efficiency and enhancing performance.SACs are characterized by isolated metal atoms uniformly dispersed on suitable supports,ensuring each metal atom serves as an independent catalytic site.This dispersion mitigates metal atom aggregation,a common issue in conventional nanocatalysts,thus enabling superior activity,selectivity,and stability.Metal−organic frameworks(MOFs)have emerged as an ideal platform for SAC synthesis due to their structural diversity,tunable coordination environments,and high surface areas.MOFs provide well-defined coordination sites that facilitate the precise stabilization of single metal atoms,presenting significant advantages over traditional supports like metal oxides and metal materials.Carbonization of MOFs yields MOF-derived carbon materials that retain key structural characteristics while offering enhanced electrical conductivity and stability,making them suitable for various catalytic applications.Recent advances in the rational design and controlled synthesis of MOF-derived SACs have significantly improved their performance in electrocatalytic processes such as the oxygen reduction reaction(ORR)and carbon dioxide reduction reaction(CO_(2)RR).However,challenges remain,including maintaining structural integrity during high-temperature carbonization,enhancing mass and electron transport and ensuring the stability of isolated metal atoms under reaction conditions.To address these challenges,strategies such as using structure-directing agents to stabilize MOF frameworks,forming high-energy porous carbon networks,and optimizing support morphologies have been developed to maximize active site exposure and accessibility.On the other hand,the interplay between active metal sites and their coordination environments is crucial in determining the catalytic activity and selectivity of SACs.Advanced computational modeling,coupled with experimental validation,has provided insights into the electronic structure of SACs and the interactions between metal atoms and supports.These insights have enabled researchers to fine-tune local atomic coordination,leading to significant enhancements in performance.For instance,modifying the coordination environment of metal atoms optimizes the binding strength of reaction intermediates,thereby improving both activity and selectivity.This account highlights our group’s contributions to MOF-derived SACs,focusing on innovative design,functionalization,and synthesis approaches that enhance catalytic activity.Notable strategies include using structure-directing agents to maintain pore connectivity during carbonization,preserving high surface areas,and enhancing mass transport.We also discuss the design of high-energy MOFderived porous carbon networks that facilitate continuous electron transport and improve the interaction between active sites and reactants,ultimately boosting catalytic efficiency.Techniques such as electrospinning have also been employed to create hierarchical porous structures and one-dimensional nanofibers,enhancing mass transport and electron transfer.The rational design of SACs requires a comprehensive understanding of the microenvironment surrounding active sites,and by leveraging computational and experimental tools,researchers can precisely control these microenvironments to achieve desired outcomes.MOF-derived SACs hold substantial promise for energy conversion and chemical synthesis.Continued research is essential to optimize their design,improve scalability,and explore new applications,ultimately advancing sustainable catalysis.This account provides an overview of the latest advancements in MOF-derived SACs,highlighting their potential as next-generation electrocatalysts and their role in sustainable energy technologies.
基金supported by the Fundamental Research Funds for the Central Universitiesthe National Natural Science Foundation of China(Nos.11774286,11374238,11574247,11374008,and 11534008)
文摘We demonstrate the generation of non-classical photon pairs in a warm S-Rb atomic vapor （＇ell with no buffer gas or polarization preserving coatings via spontaneous four-wave mixing. We obtain the photon pairs with a 1/e correlation time of 40 ns and the violation of Cauchy-Sehwartz inequality by a factor of 23 - 3. This provides a convenient and efficient method to generate photon pair sources based on an atomic ensemble.
