Bifunctional metal/zeolite materials are some of the most suitable catalysts for the direct hydroalkylation of benzene to cyclohexylbenzene.The overall catalytic performance of this reaction is strongly influenced by ...Bifunctional metal/zeolite materials are some of the most suitable catalysts for the direct hydroalkylation of benzene to cyclohexylbenzene.The overall catalytic performance of this reaction is strongly influenced by the hydrogenation,which is dependent on the metal sizes.Thus,systematically investigating the metal size effects in the hydroalkylation of benzene is essential.In this work,we successfully synthesized Ru and Pd nanoparticles on Sinopec Composition Materials No.1 zeolite with various metal sizes.We demonstrated the size-dependent catalytic activity of zeolite-supported Ru and Pd catalysts in the hydroalkylation of benzene,which can be attributed to the size-induced hydrogen spillover capability differences.Our work presents new insights into the hydroalkylation reaction and may open up a new avenue for the smart design of advanced metal/zeolite bi-functional catalysts.展开更多
Selective oxidation of methane to methanol under mild conditions has been considered as a dream reaction but suffers from poor efficiency due to the strong C-H bond of methane and easy overoxidation of the methanol pr...Selective oxidation of methane to methanol under mild conditions has been considered as a dream reaction but suffers from poor efficiency due to the strong C-H bond of methane and easy overoxidation of the methanol product.For overcoming these problems,a series of strategies has been developed for improving methanol productivity with oxidants of hydrogen peroxide and even a mixture of oxygen and hydrogen at mild temperatures.Significant achievements in these strategies using effective catalysts,such as supported metal nanoparticles,colloidal metal nanoparticles,and metal@zeolites are briefly concluded.Moreover,the current challenges,future perspectives for preparing active,selective,and stable catalysts,have been discussed.The zeolite fixed metal nanoparticle structure has been found to boost the reaction by benefiting the formation and enrichment of peroxide intermediates,which might guide the development of more efficient catalysts.展开更多
Zeolite-supported metal catalysts have important applications in various catalytic reactions,but unveiling their atomic-scale structures is always a grand challenge.The developed transmission electron microscopy(TEM)c...Zeolite-supported metal catalysts have important applications in various catalytic reactions,but unveiling their atomic-scale structures is always a grand challenge.The developed transmission electron microscopy(TEM)characterization techniques,e.g.,integrated differential-phase contrast(iDPC)scanning transmission electron microscopy(STEM)is emerging as a powerful tool for visualizing the electron beam-sensitive materials at atomic resolution,thus,providing new opportunities for imaging the exact configurations of metal species in the various channels of zeolites.This emerging topic summarizes recent progress utilizing iDPC-STEM-related technique for determination of the structures of metal species in zeolites that should offer insights into the structure-property relationships of zeolite-supported metal catalysts.A brief perspective about the new TEM technique is also presented,showing prospects in this field that will stimulate further scientific research in zeolite-supported metal catalysts.展开更多
基金supported by China Petrochemical Corporation and the National Natural Science Foundation of China(Grant Nos.U19B6002,21972168,and 22302234).
文摘Bifunctional metal/zeolite materials are some of the most suitable catalysts for the direct hydroalkylation of benzene to cyclohexylbenzene.The overall catalytic performance of this reaction is strongly influenced by the hydrogenation,which is dependent on the metal sizes.Thus,systematically investigating the metal size effects in the hydroalkylation of benzene is essential.In this work,we successfully synthesized Ru and Pd nanoparticles on Sinopec Composition Materials No.1 zeolite with various metal sizes.We demonstrated the size-dependent catalytic activity of zeolite-supported Ru and Pd catalysts in the hydroalkylation of benzene,which can be attributed to the size-induced hydrogen spillover capability differences.Our work presents new insights into the hydroalkylation reaction and may open up a new avenue for the smart design of advanced metal/zeolite bi-functional catalysts.
基金This work was supported by the National Natural Science Foundation of China(No.21932006).
文摘Selective oxidation of methane to methanol under mild conditions has been considered as a dream reaction but suffers from poor efficiency due to the strong C-H bond of methane and easy overoxidation of the methanol product.For overcoming these problems,a series of strategies has been developed for improving methanol productivity with oxidants of hydrogen peroxide and even a mixture of oxygen and hydrogen at mild temperatures.Significant achievements in these strategies using effective catalysts,such as supported metal nanoparticles,colloidal metal nanoparticles,and metal@zeolites are briefly concluded.Moreover,the current challenges,future perspectives for preparing active,selective,and stable catalysts,have been discussed.The zeolite fixed metal nanoparticle structure has been found to boost the reaction by benefiting the formation and enrichment of peroxide intermediates,which might guide the development of more efficient catalysts.
基金Theauthors thank the National Natural Science Foundation of China(U21A20326)Fundamental Research Funds for the Central Universities,Shanghai Rising-star Program(20QA1402400)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning.Additional。
文摘Zeolite-supported metal catalysts have important applications in various catalytic reactions,but unveiling their atomic-scale structures is always a grand challenge.The developed transmission electron microscopy(TEM)characterization techniques,e.g.,integrated differential-phase contrast(iDPC)scanning transmission electron microscopy(STEM)is emerging as a powerful tool for visualizing the electron beam-sensitive materials at atomic resolution,thus,providing new opportunities for imaging the exact configurations of metal species in the various channels of zeolites.This emerging topic summarizes recent progress utilizing iDPC-STEM-related technique for determination of the structures of metal species in zeolites that should offer insights into the structure-property relationships of zeolite-supported metal catalysts.A brief perspective about the new TEM technique is also presented,showing prospects in this field that will stimulate further scientific research in zeolite-supported metal catalysts.
