Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent year...Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst.展开更多
High-energy lithium-sulfur batteries(LSBs)have experienced relentless development over the past decade with discernible improvements in electrochemical performance.However,a scrutinization of the cell operation condit...High-energy lithium-sulfur batteries(LSBs)have experienced relentless development over the past decade with discernible improvements in electrochemical performance.However,a scrutinization of the cell operation conditions reveals a huge gap between the demands for practical batteries and those in the literature.Low sulfur loading,a high electrolyte/sulfur(E/S)ratio and excess anodes for lab-scale LSBs significantly offset their high-energy merit.To approach practical LSBs,high loading and lean electrolyte parameters are needed,which involve budding challenges of slow charge transfer,polysulfide precipitation and severe shuttle effects.To track these obstacles,the exploration of electrocatalysts to immobilize polysulfides and accelerate Li-S redox kinetics has been widely reported.Herein,this review aims to survey state-of-the-art catalytic materials for practical LSBs with emphasis on elucidating the correlation among catalyst design strategies,material structures and electrochemical performance.We also statistically evaluate the state-of-the-art catalyst-modified LSBs to identify the remaining discrepancy between the current advancements and the real-world requirements.In closing,we put forward our proposal for a catalytic material study to help realize practical LSBs.展开更多
Room temperature sodium–sulfur(RT Na-S)battery with high theoretical energy density and low cost has spurred tremendous interest,which is recognized as an ideal candidate for large-scale energy storage applications.H...Room temperature sodium–sulfur(RT Na-S)battery with high theoretical energy density and low cost has spurred tremendous interest,which is recognized as an ideal candidate for large-scale energy storage applications.However,serious sodium polysulfide shutting and sluggish reaction kinetics lead to rapid capacity decay and poor Coulombic efficiency.Recently,catalytic materials capable of adsorbing and catalyzing the conversion of polysulfides are profiled as a promising method to improve electrochemical performance.In this review,the research progress is summarized that the application of catalytic materials in RT Na-S battery.For the role of catalyst on the conversion of sulfur species,specific attention is focused on the influence factors of reaction rate during different redox processes.Various catalytic materials based on lightweight and high conductive carbon materials,including heteroatom-doped carbon,metals and metal compounds,single-atom and heterostructure,promote the reaction kinetic via lowered energy barrier and accelerated charge transfer.Additionally,the adsorption capacity of the catalytic materials is the key to the catalytic effect.Particular attention to the interaction between polysulfides and sulfur host materials is necessary for the exploration of catalytic mechanism.Lastly,the challenges and outlooks toward the desired design of efficient catalytic materials for RT Na-S battery are discussed.展开更多
A mechanism for the catalytically growth of vapor grown fibrous carbon (VGFC) preparing from the floating catalyst method has been proposed, in which liquid diffusion-determined diffusionof carbon atoms through cataly...A mechanism for the catalytically growth of vapor grown fibrous carbon (VGFC) preparing from the floating catalyst method has been proposed, in which liquid diffusion-determined diffusionof carbon atoms through catalyst particles is described mathematically, and the physical andchemical properties of the catalyst particIes during the growth process are taken into account.From the model the growth rate and grown length of VGFC are calculated theoretically whichcoincides with the experimental datal and the necessity of reducing gas such as hydrogen inpreparing VGFC is explained as to reduce Fe3C, which acts as intermediate catalyst shown bythe model. Fe3C formed on the surface of γ-Fe will stop the growth of carbon fiber if they cannot be reduced at once. Additionally, the growth temperature and diameter of VGFC are alsodiscussed in the paper.展开更多
Since the discovery of mesoporous silica in 1990s,there have been numerous mesoporous silica-based nanomaterials developed for catalytic applications,aiming at enhanced catalytic activity and stability.Recently,there ...Since the discovery of mesoporous silica in 1990s,there have been numerous mesoporous silica-based nanomaterials developed for catalytic applications,aiming at enhanced catalytic activity and stability.Recently,there have also been considerable interests in endowing them with hierarchical porosities to overcome the diffusional limitation for those with long unimodal channels.Present processes of making mesoporous silica largely rely on chemical sources which are relatively expensive and impose environmental concerns on their processes.In this regard,it is desirable to develop hierarchical silica supports from natural minerals.Herein,we present a series of work on surface reconstruction,modification,and functionalization to produce diatomite-based catalysts with original morphology and macro-meso-micro porosities and to test their suitability as catalyst supports for both liquid-and gas-phase reactions.Two wet-chemical routes were developed to introduce mesoporosity to both amorphous and crystalline diatomites.Importantly,we have used computational modeling to affirm that the diatomite morphology can improve catalytic performance based on fluid dynamics simulations.Thus,one could obtain this type of catalysts from numerous natural diatoms that have inherently intricate morphologies and shapes in micrometer scale.In principle,such catalytic nanocomposites acting as miniaturized industrial catalysts could be employed in microfluidic reactors for process intensification.展开更多
In this study,Co/Zr-metal organic framework(MOF)precursors were obtained by a roomtemperature liquid-phase precipitation method and the equivalent-volume impregnation method,respectively,using a Zr-MOF as the support,...In this study,Co/Zr-metal organic framework(MOF)precursors were obtained by a roomtemperature liquid-phase precipitation method and the equivalent-volume impregnation method,respectively,using a Zr-MOF as the support,and Co/Zr-MOF-M and Co/Zr-MOF-N catalysts were prepared after calcination in a hydrogen-argon mixture gases(VAr:V_(H_(2))=9:1)at 350℃for 2 h.The catalytic activities of the prepared samples for CO_(2)methanation under atmosphericpressure cold plasma were studied.The results showed that Co/Zr-MOF-M had a good synergistic effect with cold plasma.At a discharge power of 13.0 W,V_(H_(2)):VCO_(2)=4:1 and a gas flow rate of 30 ml·min^(-1),the CO_(2)conversion was 58.9%and the CH4 selectivity reached 94.7%,which was higher than for Co/Zr-MOF-N under plasma(CO_(2)conversion 24.8%,CH4 selectivity 9.8%).X-ray diffraction,scanning electron microscopy,transmission electron microscopy,N_(2)adsorption and desorption(Brunauer-Emmett-Teller)and x-ray photoelectron spectroscopy analysis results showed that Co/Zr-MOF-M and Co/Zr-MOF-N retained a good Zr-MOF framework structure,and the Co oxide was uniformly dispersed on the surface of the Zr-MOF.Compared with Co/Zr-MOF-N,the Co/Zr-MOF-M catalyst has a larger specific surface area and higher Co^(2+)/Cototaland Co/Zr ratios.Additionally,the Co oxide in Co/ZrMOF-M is distributed on the surface of the Zr-MOF in the form of porous particles,which may be the main reason why the catalytic activity of Co/Zr-MOF-M is higher than that of Co/ZrMOF-N.展开更多
Thermochemical conversion of fossil resources into fuels,chemicals,andmaterials has rapidly increased atmospheric CO_(2)levels,hindering global efforts toward achieving carbon neutrality.With the increasing push for s...Thermochemical conversion of fossil resources into fuels,chemicals,andmaterials has rapidly increased atmospheric CO_(2)levels,hindering global efforts toward achieving carbon neutrality.With the increasing push for sustainability,utilizing electrochemical technology to transform CO_(2)or biomass into value-added chemicals and to close the carbon cycle with sustainable energy sources represents a promising strategy.Expanding the scope of electrosynthesis technology is a prerequisite for the electrification of chemical manufacturing.To this end,constructing the C─N bond is considered a priority.However,a systematic review of electrocatalytic processes toward building C─N bonds using CO_(2)and biomass as carbon sources is not available.Accordingly,this review highlights the research progress in the electrosynthesis of organic nitrogen compounds from CO_(2)and biomass by C─N coupling reactions in view of catalytic materials,focusing on the enlightenment of traditional catalysis on C─N coupling and the understanding of the basis of electrochemical C─N coupling.The possibility of C─N bond in electrocatalysis is also examined from the standpoints of activation of substrates,coupling site,mechanism,and inhibition of hydrogen evolution reaction(HER).Finally,the challenges and prospects of electrocatalytic C─N coupling reactions with improved efficiency and selectivity for future development are discussed.展开更多
The insulating nature of sulfur species,sluggish reaction kinetics,and uncontrolled dissolution of lithium polysulfide(LiPS)intermediates during the complex and multiphase sulfur redox process,have severely inhibited ...The insulating nature of sulfur species,sluggish reaction kinetics,and uncontrolled dissolution of lithium polysulfide(LiPS)intermediates during the complex and multiphase sulfur redox process,have severely inhibited the applications of Li-S batteries.In this study,we report a rational strategy to accelerate the polysulfide catalysis via constructing phosphorus modulated porous CeO_(2)(P-CeO_(2))for advanced Li-S batteries.The morphology and surface analysis demonstrate that the P-CeO_(2)consists of abundant Pmodulated porous CeO_(2)nanocrystallines.The battery performance reveals that the introduction of P will lead to an improved initial capacity of 1027 mA hg^(-1)than that of bare CeO_(2)(895.7 mA hg^(-1))at 0.2 C.In addition,the P-CeO_(2)cathode can maintain a low capacity decay ratio of 0.10%per cycle after 500 cycles at 1.0 C.The coin battery tests suggest that the P-CeO_(2)cathode presents faster oxidation-reduction kinetics of LiPS and quick diffusion of Li^+ions.Meanwhile,the studies of redox processes and chemical interactions of LiPS have demonstrated the P-CeO_(2)cathode displays stronger adsorption of Li_(2)S_(6),higher redox peak current,and earlier precipitation of Li_(2)S than the bare CeO_(2).This study demonstrates for the first time that the P-modulation of metal oxide surface can simultaneously promote the catalytic reaction kinetics and chemical interaction of LiPS.We anticipate that this P-modulation method can be extended to many other nanostructured metal catalytic sites for developing affordable advanced Li-S batteries.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51902101 and 21875203)the Natural Science Foundation of Hunan Province(Nos.2021JJ40044 and 2023JJ50287)Natural Science Foundation of Jiangsu Province(No.BK20201381).
文摘Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst.
基金supported by grants from the Research Grants Council of the Hong Kong Special Administrative Region,China(Poly U25216121,Poly U15303219)the National Natural Science Foundation of China for Young Scholar(52102310)the Research Committee of the Hong Kong Polytechnic University(A-PB1 M,1-BBXK,1-CD4 M,and G-UAMV)。
文摘High-energy lithium-sulfur batteries(LSBs)have experienced relentless development over the past decade with discernible improvements in electrochemical performance.However,a scrutinization of the cell operation conditions reveals a huge gap between the demands for practical batteries and those in the literature.Low sulfur loading,a high electrolyte/sulfur(E/S)ratio and excess anodes for lab-scale LSBs significantly offset their high-energy merit.To approach practical LSBs,high loading and lean electrolyte parameters are needed,which involve budding challenges of slow charge transfer,polysulfide precipitation and severe shuttle effects.To track these obstacles,the exploration of electrocatalysts to immobilize polysulfides and accelerate Li-S redox kinetics has been widely reported.Herein,this review aims to survey state-of-the-art catalytic materials for practical LSBs with emphasis on elucidating the correlation among catalyst design strategies,material structures and electrochemical performance.We also statistically evaluate the state-of-the-art catalyst-modified LSBs to identify the remaining discrepancy between the current advancements and the real-world requirements.In closing,we put forward our proposal for a catalytic material study to help realize practical LSBs.
基金financial support from National Natural Science Foundation of China(Nos.52020105010,51972313,51927803,52072378,51902316 and 51525206)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA22010602)+2 种基金LiaoNing Revitalization Talents Program(No.XLYC1908015)Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.Y201942)the Special Projects of the Central Government in Guidance of Local Science and Technology Development(No.2020JH6/10500024)。
文摘Room temperature sodium–sulfur(RT Na-S)battery with high theoretical energy density and low cost has spurred tremendous interest,which is recognized as an ideal candidate for large-scale energy storage applications.However,serious sodium polysulfide shutting and sluggish reaction kinetics lead to rapid capacity decay and poor Coulombic efficiency.Recently,catalytic materials capable of adsorbing and catalyzing the conversion of polysulfides are profiled as a promising method to improve electrochemical performance.In this review,the research progress is summarized that the application of catalytic materials in RT Na-S battery.For the role of catalyst on the conversion of sulfur species,specific attention is focused on the influence factors of reaction rate during different redox processes.Various catalytic materials based on lightweight and high conductive carbon materials,including heteroatom-doped carbon,metals and metal compounds,single-atom and heterostructure,promote the reaction kinetic via lowered energy barrier and accelerated charge transfer.Additionally,the adsorption capacity of the catalytic materials is the key to the catalytic effect.Particular attention to the interaction between polysulfides and sulfur host materials is necessary for the exploration of catalytic mechanism.Lastly,the challenges and outlooks toward the desired design of efficient catalytic materials for RT Na-S battery are discussed.
文摘A mechanism for the catalytically growth of vapor grown fibrous carbon (VGFC) preparing from the floating catalyst method has been proposed, in which liquid diffusion-determined diffusionof carbon atoms through catalyst particles is described mathematically, and the physical andchemical properties of the catalyst particIes during the growth process are taken into account.From the model the growth rate and grown length of VGFC are calculated theoretically whichcoincides with the experimental datal and the necessity of reducing gas such as hydrogen inpreparing VGFC is explained as to reduce Fe3C, which acts as intermediate catalyst shown bythe model. Fe3C formed on the surface of γ-Fe will stop the growth of carbon fiber if they cannot be reduced at once. Additionally, the growth temperature and diameter of VGFC are alsodiscussed in the paper.
基金the financial support provided by the National Research Foundation (NRF), Prime Minister’s Office, Singapore, under its Campus for Research Excellence and Technological Enterprise (CREATE) programpartially funded by the National University of Singapore under its Flagship Green Energy Program (GEP), Agency for Science, Technology and Research (A*STAR) under its Low Carbon Energy Research Funding Initiative (LCER-FI)Chongqing Science and Technology Research and Development Base Construction Project (cstc2013gjhz0029)
文摘Since the discovery of mesoporous silica in 1990s,there have been numerous mesoporous silica-based nanomaterials developed for catalytic applications,aiming at enhanced catalytic activity and stability.Recently,there have also been considerable interests in endowing them with hierarchical porosities to overcome the diffusional limitation for those with long unimodal channels.Present processes of making mesoporous silica largely rely on chemical sources which are relatively expensive and impose environmental concerns on their processes.In this regard,it is desirable to develop hierarchical silica supports from natural minerals.Herein,we present a series of work on surface reconstruction,modification,and functionalization to produce diatomite-based catalysts with original morphology and macro-meso-micro porosities and to test their suitability as catalyst supports for both liquid-and gas-phase reactions.Two wet-chemical routes were developed to introduce mesoporosity to both amorphous and crystalline diatomites.Importantly,we have used computational modeling to affirm that the diatomite morphology can improve catalytic performance based on fluid dynamics simulations.Thus,one could obtain this type of catalysts from numerous natural diatoms that have inherently intricate morphologies and shapes in micrometer scale.In principle,such catalytic nanocomposites acting as miniaturized industrial catalysts could be employed in microfluidic reactors for process intensification.
基金supported by National Natural Science Foundation of China(Nos.21673026,11605020)Innovative Training Program for College Student of Liaoning Province(No.S202011258068)。
文摘In this study,Co/Zr-metal organic framework(MOF)precursors were obtained by a roomtemperature liquid-phase precipitation method and the equivalent-volume impregnation method,respectively,using a Zr-MOF as the support,and Co/Zr-MOF-M and Co/Zr-MOF-N catalysts were prepared after calcination in a hydrogen-argon mixture gases(VAr:V_(H_(2))=9:1)at 350℃for 2 h.The catalytic activities of the prepared samples for CO_(2)methanation under atmosphericpressure cold plasma were studied.The results showed that Co/Zr-MOF-M had a good synergistic effect with cold plasma.At a discharge power of 13.0 W,V_(H_(2)):VCO_(2)=4:1 and a gas flow rate of 30 ml·min^(-1),the CO_(2)conversion was 58.9%and the CH4 selectivity reached 94.7%,which was higher than for Co/Zr-MOF-N under plasma(CO_(2)conversion 24.8%,CH4 selectivity 9.8%).X-ray diffraction,scanning electron microscopy,transmission electron microscopy,N_(2)adsorption and desorption(Brunauer-Emmett-Teller)and x-ray photoelectron spectroscopy analysis results showed that Co/Zr-MOF-M and Co/Zr-MOF-N retained a good Zr-MOF framework structure,and the Co oxide was uniformly dispersed on the surface of the Zr-MOF.Compared with Co/Zr-MOF-N,the Co/Zr-MOF-M catalyst has a larger specific surface area and higher Co^(2+)/Cototaland Co/Zr ratios.Additionally,the Co oxide in Co/ZrMOF-M is distributed on the surface of the Zr-MOF in the form of porous particles,which may be the main reason why the catalytic activity of Co/Zr-MOF-M is higher than that of Co/ZrMOF-N.
文摘Thermochemical conversion of fossil resources into fuels,chemicals,andmaterials has rapidly increased atmospheric CO_(2)levels,hindering global efforts toward achieving carbon neutrality.With the increasing push for sustainability,utilizing electrochemical technology to transform CO_(2)or biomass into value-added chemicals and to close the carbon cycle with sustainable energy sources represents a promising strategy.Expanding the scope of electrosynthesis technology is a prerequisite for the electrification of chemical manufacturing.To this end,constructing the C─N bond is considered a priority.However,a systematic review of electrocatalytic processes toward building C─N bonds using CO_(2)and biomass as carbon sources is not available.Accordingly,this review highlights the research progress in the electrosynthesis of organic nitrogen compounds from CO_(2)and biomass by C─N coupling reactions in view of catalytic materials,focusing on the enlightenment of traditional catalysis on C─N coupling and the understanding of the basis of electrochemical C─N coupling.The possibility of C─N bond in electrocatalysis is also examined from the standpoints of activation of substrates,coupling site,mechanism,and inhibition of hydrogen evolution reaction(HER).Finally,the challenges and prospects of electrocatalytic C─N coupling reactions with improved efficiency and selectivity for future development are discussed.
基金financially supported by the National Key R&D Program of China(2021YFE0205000)the National Natural Science Foundation of China(No.52173133)+5 种基金the Science and Technology Project of Sichuan Province(Nos.2021YFH0135 and 2020YFH0087)the China Postdoctoral Science Foundation(2021M692303)the full-time Postdoctoral Foundation of Sichuan University(2021SCU12013)the support of the State Key Laboratory of Polymer Materials Engineering(No.sklpme 2021-4-02)the Fundamental Research Funds for the Central Universitiesthe Alexander von Humboldt Fellowship。
文摘The insulating nature of sulfur species,sluggish reaction kinetics,and uncontrolled dissolution of lithium polysulfide(LiPS)intermediates during the complex and multiphase sulfur redox process,have severely inhibited the applications of Li-S batteries.In this study,we report a rational strategy to accelerate the polysulfide catalysis via constructing phosphorus modulated porous CeO_(2)(P-CeO_(2))for advanced Li-S batteries.The morphology and surface analysis demonstrate that the P-CeO_(2)consists of abundant Pmodulated porous CeO_(2)nanocrystallines.The battery performance reveals that the introduction of P will lead to an improved initial capacity of 1027 mA hg^(-1)than that of bare CeO_(2)(895.7 mA hg^(-1))at 0.2 C.In addition,the P-CeO_(2)cathode can maintain a low capacity decay ratio of 0.10%per cycle after 500 cycles at 1.0 C.The coin battery tests suggest that the P-CeO_(2)cathode presents faster oxidation-reduction kinetics of LiPS and quick diffusion of Li^+ions.Meanwhile,the studies of redox processes and chemical interactions of LiPS have demonstrated the P-CeO_(2)cathode displays stronger adsorption of Li_(2)S_(6),higher redox peak current,and earlier precipitation of Li_(2)S than the bare CeO_(2).This study demonstrates for the first time that the P-modulation of metal oxide surface can simultaneously promote the catalytic reaction kinetics and chemical interaction of LiPS.We anticipate that this P-modulation method can be extended to many other nanostructured metal catalytic sites for developing affordable advanced Li-S batteries.