Bimetallic catalysts typically exploit unique synergetic effects between two metal species to achieve their catalytic effect.Understanding the mechanism of CO oxidation using hybrid heterogeneous catalysts is importan...Bimetallic catalysts typically exploit unique synergetic effects between two metal species to achieve their catalytic effect.Understanding the mechanism of CO oxidation using hybrid heterogeneous catalysts is important for effective catalyst design and environmental protection.Herein,we report a Bi-Au/SiO_(2)tandem bimetallic catalyst for the oxidation of CO over the Au/SiO_(2)surface,which was monitored using near-ambient-pressure X-ray photoelectron spectroscopy.The Au-decorated SiO_(2)catalyst exhibited scarce activity in the CO oxidation reaction;however,the introduction of Bi to the Au/SiO_(2)system promoted the catalytic activity.The mechanism is thought to involve the dissociation O_(2)molecules in the presence of Bi,which results in spillover of the O species to adjacent Au atoms,thereby forming Au^(δ+).Further CO adsorption,followed by thermal treatment,facilitated the oxidation of CO at the Au-Bi interface,resulting in a reversible reversion to the neutral Au valence state.Our work provides insight into the mechanism of CO oxidation on tandem surfaces and will facilitate the rational design of other Au-based catalysts.展开更多
Copper (Cu) is a special electrocatalyst for CO_(2) reduction reaction (CO_(2)RR) to multi-carbon products.Experimentally introducing grain boundaries (GBs) into Cu-based catalysts is an efficient strategy to improve ...Copper (Cu) is a special electrocatalyst for CO_(2) reduction reaction (CO_(2)RR) to multi-carbon products.Experimentally introducing grain boundaries (GBs) into Cu-based catalysts is an efficient strategy to improve the selectivity of C^(2+) products.However,it is still elusive for the C^(2+) product generation on Cu GBs due to the complex active sites.In this work,we found that the tandem catalysis pathway on adjacent active motifs of Cu GB is responsible for the enhanced activity for C^(2+)production by first principles calculations.By electronic structure analysis shows,the d-band center of GB site is close to the Fermi level than Cu(100) facet,the Cu atomic sites at grain boundary have shorter bond length and stronger bonding with*CO,which can enhance the adsorption of*CO at GB sites.Moreover,CO_(2)protonation is more favorable on the region Ⅲ motif (0.84 e V) than at Cu(100) site (1.35 e V).Meanwhile,the region Ⅱ motif also facilitate the C–C coupling (0.72 e V) compared to the Cu(100) motif (1.09 e V).Therefore,the region Ⅲ and Ⅱ motifs form a tandem catalysis pathway,which promotes the C^(2+)selectivity on Cu GBs.This work provides new insights into CO_(2)RR process.展开更多
One-pot tandem catalysis has been regarded as one of the most atomic economic ways to produce secondary amines,the important platform molecules for chemical synthesis and pharmaceutical manufacture,but it is facing se...One-pot tandem catalysis has been regarded as one of the most atomic economic ways to produce secondary amines,the important platform molecules for chemical synthesis and pharmaceutical manufacture,but it is facing serious issues in overall efficiency.New promotional effects are highly desired for boosting the activity and regulating the selectivity of conventional tandem catalysts.In this work,we report a high-performance tandem catalyst with maximized synergistic effect among each counterpart by preciously manipulating the spatial structure,which involves the active CeO_(2)/Pt component as kernel,the densely-coated N-doped C(NC)layer as selectivity controller,and the differentially-grown Co species as catalytic performance regulators.Through comprehensive investigations,the unique growth mechanism and the promotion effect of Co regulators are clarified.Specifically,the surface-landed Co clusters(Cocs)are crucial to selectivity by altering the adsorption configuration of benzylideneaniline intermediates.Meanwhile,the inner Co particles(Cops)are essential for activity by denoting their electrons to neighboring Ptps.Benefiting from the unique promotion effect,a remarkably-improved catalytic efficiency(100%nitrobenzene conversion with 94%N-benzylaniline selectivity)is achieved at a relatively low temperature of 80℃,which is much better than that of CeO_(2)/Pt(100%nitrobenzene conversion with 12%N-benzylaniline selectivity)and CeO_(2)/Pt/NC(35%nitrobenzene conversion with 94%benzylideneaniline selectivity).展开更多
The special electronic characteristics and high atom usage efficiency of metal-nitrogen-carbon(M-N-C)materials have made them extremely attractive for oxygen reduction reactions(ORRs).However,it is inevitable that hyd...The special electronic characteristics and high atom usage efficiency of metal-nitrogen-carbon(M-N-C)materials have made them extremely attractive for oxygen reduction reactions(ORRs).However,it is inevitable that hydrogen peroxide(H_(2)O_(2))will be formed via the two-electron pathway in ORRs.Herein,the Cu nanoparticles(NPs)have been encapsulated into Ni doped hollow mesoporous carbon spheres(Ni-HMCS)to reduce the generation of H_(2)O_(2)in ORR.Electrochemical tests confirm that the introduction of Cu NPs improves the ORR performance greatly.The obtained Cu/Ni-HMCS exhibits a half-wave potential of 0.82 V vs.reversible hydrogen electrode and a limited current density of 5.5 mA cm^(-2),which is comparable with the commercial Pt/C.Moreover,Cu/Ni-HMCS has been used in Zn-air battery,demonstrating a high power density of 161 mW cm^(-2)and a long-term recharge capability(50 h at 5 mA cm^(-2)).The theoretical calculation proposes a tandem catalysis pathway for Cu/Ni multi-sites catalysis,that is,H_(2)O_(2)released from the Ni-N_(4)and Cu-N_(4)sites migrates to the Cu(111)face,on which the captive H_(2)O_(2)is further reduced to H_(2)O.This work demonstrates an interesting tandem catalytic pathway of dual-metal multi-sites for ORR,which provides an insight into the development of effective fuel cell electrocatalysts.展开更多
Polyolefins have the largest share in plastic waste,so it is vital to transform these end-of-life wastes into highly valued products.We present here a new catalytic method to produce aromatics using PE as a carbon sou...Polyolefins have the largest share in plastic waste,so it is vital to transform these end-of-life wastes into highly valued products.We present here a new catalytic method to produce aromatics using PE as a carbon source.Our results indicate that polyethylene(PE)and CO_(2)can be converted into aromatics and CO simultaneously,achieving a high transformation rate and a 64.0%selectivity toward aromatics below 400℃ by Cu-Fe_(3)O_(4)and Zn/ZSM-5 tandem catalysis.Notably,the established theoretical limit of 50%selectivity toward aromatics in PE aromatization is surpassed.This is attributed to the coexistence of reverse water-gas shift,which converts another feed,CO_(2),with hydrogen to produce valuable CO,confirmed by^(13)C isotope studies.It consumes excessive hydrogen generated during PE aromatization to produce CO and mitigates the production of light alkanes from hydrogen transfer reactions,thereby augmenting the formation of aromatic compounds.Our research offers a new approach to valorizing two prevalent waste carbon sources:waste plastic and CO_(2),which is useful for designing a new strategy for upcycling waste carbon resources.展开更多
The generation of multifunctional isolated active sites in zeolite supports is an attractive method for integrating multistep sequential reactions into a single‐pass tandem catalytic reaction.In this study,bifunction...The generation of multifunctional isolated active sites in zeolite supports is an attractive method for integrating multistep sequential reactions into a single‐pass tandem catalytic reaction.In this study,bifunctional TiSn‐Beta zeolite was prepared by a simple and scalable post‐synthesis approach,and it was utilized as an efficient heterogeneous catalyst for the tandem conversion of alkenes to 1,2‐diols.The isolated Ti and Sn Lewis acid sites within the TiSn‐Beta zeolite can efficiently integrate alkene epoxidation and epoxide hydration in tandem in a zeolite microreactor to achieve one‐step conversion of alkenes to 1,2‐diols with a high selectivity of>90%.Zeolite confinement effects result in high tandem rates of alkene epoxidation and epoxide hydration as well as high selectivity toward the desired product.Further,the novel method demonstrated herein can be employed to other tandem catalytic reactions for sustainable chemical production.展开更多
Tandem catalytic systems, consisting of ethylene bis（indenyl） zirconium dichloride with two different cocatalysts, alkylaluminum（diethylaluminium chloride or trialkylaluminum） and methylaluminoxane, were employed ...Tandem catalytic systems, consisting of ethylene bis（indenyl） zirconium dichloride with two different cocatalysts, alkylaluminum（diethylaluminium chloride or trialkylaluminum） and methylaluminoxane, were employed in preparing branched polyethylene from ethylene as sole monomer. The catalytic system rac-Et（Ind）2Zr Cl2/Al Et2Cl/MAO exhibited high incorporation（29.0/1000C）. The oligomerization and copolymerization reaction conditions in the tandem catalytic system, as well as the different cocatalysts, have effects on the catalytic activity and the properties of the obtained polymer, such as melting temperature, crystallinity, molecular weight and molecular weight distribution. Moreover, the oligomerization reaction condition is the main factor in altering the properties and structures of polyethylene.展开更多
Tandem catalysis for the hydrogenation rearrangement of furfural(FA)provides an attractive solution for manufacturing cyclopentanone(CPO)from renewable biomass resources.The Cu-Ni/Al-MCM-41 catalyst was synthesized an...Tandem catalysis for the hydrogenation rearrangement of furfural(FA)provides an attractive solution for manufacturing cyclopentanone(CPO)from renewable biomass resources.The Cu-Ni/Al-MCM-41 catalyst was synthesized and afforded excellent catalytic performance with 99.0%conversion and 97.7%selectivity to CPO in a near-neutral solution under 2.0 MPa H2 at 160℃ for 5 h,much higher than those on other molecular sieve supports including MCM-41,SBA-15,HY,and ZSM-5.A small amount of Al highly dispersed in MCM-41 plays an anchoring role and ensures the formation of highly dispersed CuNi bimetallic nanoparticles(NPs).The remarkably improved catalytic performance may be attributed to the bimetallic synergistic and charge transfer effects.In addition,the initial FA concentration and the aqueous system pH required precise control to minimize polymerization and achieve high selectivity of CPO.Fourier transform infrared spectroscopy and mass spectra results indicated that polymerization was sensitive to pH values.Under acidic conditions,FA and intermediate furfuryl alcohol polymerize,while the intermediate 4-hydroxy-2-cyclopentenone mainly polymerizes under alkaline conditions,blocking the cascade of multiple reactions.Therefore,near-neutral conditions are most suitable for minimizing the impact of polymerization.This study provides a useful solution for the current universal problems of polymerization side reactions and low carbon balance for biomass conversion.展开更多
Tandem catalysis,capable of decoupling individual steps,provides a feasible way to build a high-efficiency CO_(2) electro-conversion system for multicarbons(C_(2+)).The construction of electrocatalytic materials is on...Tandem catalysis,capable of decoupling individual steps,provides a feasible way to build a high-efficiency CO_(2) electro-conversion system for multicarbons(C_(2+)).The construction of electrocatalytic materials is one of focusing issues.Herein,we fabricated a single atom involved multivalent oxide-derived Cu composite material and found it inclined to reconstruct into oxygen-deficient multiphase Cu based species hybridized with monatomic Ni on N doped C matrix.In this prototype,rapid CO generation and C-C coupling are successively achieved on NiN4 sites and surface amorphized Cu species with defects,resembling a micro-production line.In this way,the in situ formed tandem catalyst exhibited a high Faradaic efficiency(FE)of~78%for C_(2+)products along with satisfactory durability over 50 h.Particularly,the reconstruction-induced amorphous layer with abundant asymmetric sites should be favorable to improve the ethanol selectivity(FE:63%),which is about 10 times higher than that of the non-tandem Cu-based contrast material.This work offers a new approach for manipulating tandem catalyst systems towards enhancing C_(2+)products.展开更多
Carbon dioxide emissions have increased due to the consumption of fossil fuels,making the neutralization and utilization of CO_(2) a pressing issue.As a clean and efficient energy conversion process,electrocatalytic r...Carbon dioxide emissions have increased due to the consumption of fossil fuels,making the neutralization and utilization of CO_(2) a pressing issue.As a clean and efficient energy conversion process,electrocatalytic reduction can reduce carbon dioxide into a series of alcohols and acidic organic molecules,which can effectively realize the utilization and transformation of carbon dioxide.This review focuses on the tuning strategies and structure effects of catalysts for the electrocatalytic CO_(2) reduction reaction(CO_(2)RR).The tuning strategies for the active sites of catalysts have been reviewed from intrinsic and external perspectives.The structure effects for the CO_(2)RR catalysts have also been discussed,such as tandem catalysis,synergistic effects and confinement catalysis.We expect that this review about tuning strategies and structure effects can provide guidance for designing highly efficient CO_(2)RR electrocatalysts.展开更多
Heterojunction-based photocatalyst plays an important role in the various heterogeneous catalyses.Z-scheme photocatalytic systems with two semiconductor materials are suitable for harvesting solar energy,while the adv...Heterojunction-based photocatalyst plays an important role in the various heterogeneous catalyses.Z-scheme photocatalytic systems with two semiconductor materials are suitable for harvesting solar energy,while the advanced nanostructuring tools for the fabrication of Z-scheme heterojunction are limited.Here,WO_(3)/MoS_(2)(W/M_(0.2))heterojunction composites were constructed in a microfluidic system with enhanced assembly efficiency,and the photocatalytic performance has been investigated using X-ray photoelectron spectroscopy(XPS),MottSchottky(M-S)analysis and gas chromatograph-mass spectrometer(GC-MS).In addition,in the reduction of nitrobenzene,the photogenerated hole(h^(+))oxidation of formic acid(HCOOH)provides the hydrogen source and the deposited Pd nanoparticles are enriched with photogenerated electrons for improving the transfer hydrogenation efficiency.The microfluidic-prepared tandem photocatalyst gives a meaningful guidance for the design and synthesis of heterojunction catalysts,which is promising for energy maximizing control systems.展开更多
Artificial photosynthesis in carbon dioxide(CO_(2))conversion into value-added chemicals attracts considerable attention but suffers from the low activity induced by sluggish separation of photogenerated carriers and ...Artificial photosynthesis in carbon dioxide(CO_(2))conversion into value-added chemicals attracts considerable attention but suffers from the low activity induced by sluggish separation of photogenerated carriers and the kinetic bottleneck-induced unsatisfied selectivity.Herein,we prepare a new-style Bi/TiO_(2) catalyst formed by pinning bismuth clusters on TiO_(2) nanowires through being confined by pores,which exhibits high activity and selectivity towards photocatalytic production of CH_(4) from CO_(2).Boosted charge transfer from TiO_(2) through Bi to the reactants is revealed via in situ X-ray photon spectroscopy and time-resolved photoluminescence(PL).Further,in situ Fourier transform infrared results confirm that Bi/TiO_(2) not only overcomes the multi-electron kinetics challenge of CO_(2) to CH_(4) via boosting charge transfer,but also facilitates proton production and transfer as well as the intermediates*CHO and*CH_(3)O generation,ultimately achieving the tandem catalysis towards methanation.Theoretical calculation also underlies that the more favorable reaction step from*CO to*CHO on Bi/TiO_(2) results in CH_(4) production with higher selectivity.Our work brings new insights into rational design of photocatalysts with high performance and the formation mechanism of CO_(2) to CH_(4) for solar energy storage in future.展开更多
Rational design and synthesis of multimetallic nanostructures(NSs)are fundamentally important for electrochemical CO_(2)reduction reaction(CO_(2)RR).Herein,a multi-step seed-mediated growth method is applied to synthe...Rational design and synthesis of multimetallic nanostructures(NSs)are fundamentally important for electrochemical CO_(2)reduction reaction(CO_(2)RR).Herein,a multi-step seed-mediated growth method is applied to synthesize asymmetric AuAgCu heterostructures using Au nanobipyramids as nucleation seeds,in which their composition and structures are well controlled.We find that the selectivity of C_(2)products for CO_(2)RR could be effectively regulated by tandem catalysis and electronic effect over trimetallic AuAgCu heterostructures.Particularly,the Faraday efficiency toward ethanol could reach up to 37.5%at a potential of−0.8 V versus reversible hydrogen electrode over asymmetric Au1Ag1Cu5 heterostructures with segregated domains of three constituent metals.This work provides an efficient strategy for the synthesis of multicomponent architectures to boost their promising application in CO_(2)RR.展开更多
This review provides a comprehensive overview of the distinguished academic career and scientific accomplishments of Prof.Noritatsu Tsubaki at the University of Toyama.For over 35 years,he has dedicated himself to the...This review provides a comprehensive overview of the distinguished academic career and scientific accomplishments of Prof.Noritatsu Tsubaki at the University of Toyama.For over 35 years,he has dedicated himself to the research field of one-carbon(C1)chemistry,including catalytic conversion of C1 molecules to valuable chemicals and superclean fuels,innovative catalyst and reactor development,and the design of new catalytic reactions and processes.Organized chronologically,this review highlights Prof.Tsubaki’s academic contributions from 1990,when he studied and worked at The University of Tokyo,to his current role as a full professor at the University of Toyama.The academic section of this review is divided into three main parts,focusing on Prof.Tsubaki’s pioneering work in C1 chemistry.We believe that this review will serve as a highly valuable reference for colleagues in the fields of C1 chemistry and catalysis,and inspire the development of more original and groundbreaking research.展开更多
The emergence of metal nanoclusters with atomically precise compositions and structures provides an opportunity for in-depth investigation of catalysis mechanisms and structure−property correlations at the nanoscale.H...The emergence of metal nanoclusters with atomically precise compositions and structures provides an opportunity for in-depth investigation of catalysis mechanisms and structure−property correlations at the nanoscale.However,a serious problem for metal nanocluster catalysts is that the ligands inhibit the catalytic activity through deactivating the surface of the nanoclusters.Here,we introduce a novel catalytic mode for metal nanoclusters,in which the nanoclusters initiate the catalysis via single electron transfer(SET)without destroying the integrity of nanoclusters,providing a solution for the contradiction between activity and stability of metal nanoclusters.We illustrated that the novel activation mode featured low catalyst loading(0.01 mol%),high TOF,mild reaction conditions,and easy recycling of catalyst in alkyne hydroborylation,which often suffered from poor selectivity,low functional group tolerance,etc.Furthermore,the catalyst[Au_(1)Cu_(14)(TBBT)_(12)(PPh_(3))_(6)]^(+)(TBBTH:p-tert-butylthiophenol)can be applied in highly efficient tandem processes such as hydroborylation−deuteration and hydroborylation−isomerization,demonstrating the utility of the introduced activation mode for metal nanoclusters.展开更多
Ethylene oxide(EO)and ethylene glycol(EG)are two important commodity chemicals and are industrially produced from petroleum-derived ethylene via thermocatalytic processes.The overoxidation of ethylene and the implemen...Ethylene oxide(EO)and ethylene glycol(EG)are two important commodity chemicals and are industrially produced from petroleum-derived ethylene via thermocatalytic processes.The overoxidation of ethylene and the implementation of high temperature and pressure lead to substantial CO_(2)emission.Renewable energy-driven electrocatalysis provides a low-carbon route for upgrading ethylene under mild conditions,especially when it couples with ethylene electrosynthesis from CO_(2).In this minireview,we summarize recent achievements in the selective electrocatalytic oxidation of ethylene to EO and EG.Three main reaction routes including direct electrocatalytic oxidation with water,indirect electrocatalytic oxidation with halide mediators,and tandem electrocatalytic and thermocatalytic oxidation with hydrogen peroxide intermediate,are discussed.Some representative catalyst systems and reactor designs are exemplified.We discuss the existing scientific and technical challenges of electrocatalytic ethylene upgrading in terms of reaction rate,selectivity,and long-term stability,and propose future research directions and opportunities for pushing the process towards practical application.展开更多
Electrochemical carbon dioxide reduction(CO_(2)RR)plays an important role in solving the problem of high concentration of CO_(2)in the atmosphere and realizing carbon cycle.Core-shell structure has many unique feature...Electrochemical carbon dioxide reduction(CO_(2)RR)plays an important role in solving the problem of high concentration of CO_(2)in the atmosphere and realizing carbon cycle.Core-shell structure has many unique features including tandem catalysis,lattice strain effect,defect engineering,which exhibit great potential in electrocatalysis.In this review,we focus on the advanced core-shell metal-based catalysts(CMCs)for electrochemical CO_(2)RR.The recent progress of CMCs in electrocatalytic CO_(2)RR is described as the follow-ing aspects:(1)The mechanism of electrochemical CO_(2)RR and evaluation parameters of electrocatalyst performance,(2)preparation methods of core-shell metal catalysts and core-shell structural advantages and(3)advanced CMCs towards electrochemical CO_(2)RR.Finally,we make a brief conclusion and propose the opportunities and challenges in the field of electrochemical CO_(2)RR.展开更多
基金the National Natural Science Foundation of China(Nos.11874380 and 22002183)the National Key Research and Development Program of China(No.2021YFA1600800).
文摘Bimetallic catalysts typically exploit unique synergetic effects between two metal species to achieve their catalytic effect.Understanding the mechanism of CO oxidation using hybrid heterogeneous catalysts is important for effective catalyst design and environmental protection.Herein,we report a Bi-Au/SiO_(2)tandem bimetallic catalyst for the oxidation of CO over the Au/SiO_(2)surface,which was monitored using near-ambient-pressure X-ray photoelectron spectroscopy.The Au-decorated SiO_(2)catalyst exhibited scarce activity in the CO oxidation reaction;however,the introduction of Bi to the Au/SiO_(2)system promoted the catalytic activity.The mechanism is thought to involve the dissociation O_(2)molecules in the presence of Bi,which results in spillover of the O species to adjacent Au atoms,thereby forming Au^(δ+).Further CO adsorption,followed by thermal treatment,facilitated the oxidation of CO at the Au-Bi interface,resulting in a reversible reversion to the neutral Au valence state.Our work provides insight into the mechanism of CO oxidation on tandem surfaces and will facilitate the rational design of other Au-based catalysts.
基金the National Natural Science Foundation of China(21872174,22002189,U1932148)the International Science and Technology Cooperation Program(2017YFE0127800,2018YFE0203402)+5 种基金the Hunan Provincial Science and Technology Program(2017XK2026)the Hunan Province Key Field R&D Program(2020WK2002)the Hunan Provincial Natural Science Foundation of China(2020JJ2041,2020JJ5691)the Shenzhen Science and Technology Innovation Project(JCYJ20180307151313532)the Fundamental Research Funds for the Central Universities of Central South University。
文摘Copper (Cu) is a special electrocatalyst for CO_(2) reduction reaction (CO_(2)RR) to multi-carbon products.Experimentally introducing grain boundaries (GBs) into Cu-based catalysts is an efficient strategy to improve the selectivity of C^(2+) products.However,it is still elusive for the C^(2+) product generation on Cu GBs due to the complex active sites.In this work,we found that the tandem catalysis pathway on adjacent active motifs of Cu GB is responsible for the enhanced activity for C^(2+)production by first principles calculations.By electronic structure analysis shows,the d-band center of GB site is close to the Fermi level than Cu(100) facet,the Cu atomic sites at grain boundary have shorter bond length and stronger bonding with*CO,which can enhance the adsorption of*CO at GB sites.Moreover,CO_(2)protonation is more favorable on the region Ⅲ motif (0.84 e V) than at Cu(100) site (1.35 e V).Meanwhile,the region Ⅱ motif also facilitate the C–C coupling (0.72 e V) compared to the Cu(100) motif (1.09 e V).Therefore,the region Ⅲ and Ⅱ motifs form a tandem catalysis pathway,which promotes the C^(2+)selectivity on Cu GBs.This work provides new insights into CO_(2)RR process.
基金supported by financial aid from the National Science and Technology Major Project of China(No.2021YFB3500700)the National Natural Science Foundation of China(Nos.22020102003,22025506,and 22271274)the Program of Science and Technology Development Plan of Jilin Province of China(Nos.20230101035JC and 20230101022JC).
文摘One-pot tandem catalysis has been regarded as one of the most atomic economic ways to produce secondary amines,the important platform molecules for chemical synthesis and pharmaceutical manufacture,but it is facing serious issues in overall efficiency.New promotional effects are highly desired for boosting the activity and regulating the selectivity of conventional tandem catalysts.In this work,we report a high-performance tandem catalyst with maximized synergistic effect among each counterpart by preciously manipulating the spatial structure,which involves the active CeO_(2)/Pt component as kernel,the densely-coated N-doped C(NC)layer as selectivity controller,and the differentially-grown Co species as catalytic performance regulators.Through comprehensive investigations,the unique growth mechanism and the promotion effect of Co regulators are clarified.Specifically,the surface-landed Co clusters(Cocs)are crucial to selectivity by altering the adsorption configuration of benzylideneaniline intermediates.Meanwhile,the inner Co particles(Cops)are essential for activity by denoting their electrons to neighboring Ptps.Benefiting from the unique promotion effect,a remarkably-improved catalytic efficiency(100%nitrobenzene conversion with 94%N-benzylaniline selectivity)is achieved at a relatively low temperature of 80℃,which is much better than that of CeO_(2)/Pt(100%nitrobenzene conversion with 12%N-benzylaniline selectivity)and CeO_(2)/Pt/NC(35%nitrobenzene conversion with 94%benzylideneaniline selectivity).
基金supported by the National Key Research and Development Program of China(2021YFA1501500 and 2018YFA0704502)the National Natural Science Foundation of China(22171265,22201286,22033008 and 22220102005)+2 种基金Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZZ103)the Open Research Fund of CNMGE Platform&NSCC-TJthe Open Science Promotion Plan 2023 of CSTCloud。
文摘The special electronic characteristics and high atom usage efficiency of metal-nitrogen-carbon(M-N-C)materials have made them extremely attractive for oxygen reduction reactions(ORRs).However,it is inevitable that hydrogen peroxide(H_(2)O_(2))will be formed via the two-electron pathway in ORRs.Herein,the Cu nanoparticles(NPs)have been encapsulated into Ni doped hollow mesoporous carbon spheres(Ni-HMCS)to reduce the generation of H_(2)O_(2)in ORR.Electrochemical tests confirm that the introduction of Cu NPs improves the ORR performance greatly.The obtained Cu/Ni-HMCS exhibits a half-wave potential of 0.82 V vs.reversible hydrogen electrode and a limited current density of 5.5 mA cm^(-2),which is comparable with the commercial Pt/C.Moreover,Cu/Ni-HMCS has been used in Zn-air battery,demonstrating a high power density of 161 mW cm^(-2)and a long-term recharge capability(50 h at 5 mA cm^(-2)).The theoretical calculation proposes a tandem catalysis pathway for Cu/Ni multi-sites catalysis,that is,H_(2)O_(2)released from the Ni-N_(4)and Cu-N_(4)sites migrates to the Cu(111)face,on which the captive H_(2)O_(2)is further reduced to H_(2)O.This work demonstrates an interesting tandem catalytic pathway of dual-metal multi-sites for ORR,which provides an insight into the development of effective fuel cell electrocatalysts.
基金supported by the National Key R&D Program of China(grant nos.2021YFA1501700 and 2022YFA1504800)National Science Foundation of China(grant nos.22272114,22072002,21725301,22232001,21932002,and 21821004)+2 种基金Fundamental Research Funds from Sichuan University(grant no.2022SCUNL103)the Funding for Hundred Talent Program of Sichuan University(grant no.20822041E4079)D.M.acknowledges support from the Tencent Foundation through the XPLORER PRIZE.
文摘Polyolefins have the largest share in plastic waste,so it is vital to transform these end-of-life wastes into highly valued products.We present here a new catalytic method to produce aromatics using PE as a carbon source.Our results indicate that polyethylene(PE)and CO_(2)can be converted into aromatics and CO simultaneously,achieving a high transformation rate and a 64.0%selectivity toward aromatics below 400℃ by Cu-Fe_(3)O_(4)and Zn/ZSM-5 tandem catalysis.Notably,the established theoretical limit of 50%selectivity toward aromatics in PE aromatization is surpassed.This is attributed to the coexistence of reverse water-gas shift,which converts another feed,CO_(2),with hydrogen to produce valuable CO,confirmed by^(13)C isotope studies.It consumes excessive hydrogen generated during PE aromatization to produce CO and mitigates the production of light alkanes from hydrogen transfer reactions,thereby augmenting the formation of aromatic compounds.Our research offers a new approach to valorizing two prevalent waste carbon sources:waste plastic and CO_(2),which is useful for designing a new strategy for upcycling waste carbon resources.
文摘The generation of multifunctional isolated active sites in zeolite supports is an attractive method for integrating multistep sequential reactions into a single‐pass tandem catalytic reaction.In this study,bifunctional TiSn‐Beta zeolite was prepared by a simple and scalable post‐synthesis approach,and it was utilized as an efficient heterogeneous catalyst for the tandem conversion of alkenes to 1,2‐diols.The isolated Ti and Sn Lewis acid sites within the TiSn‐Beta zeolite can efficiently integrate alkene epoxidation and epoxide hydration in tandem in a zeolite microreactor to achieve one‐step conversion of alkenes to 1,2‐diols with a high selectivity of>90%.Zeolite confinement effects result in high tandem rates of alkene epoxidation and epoxide hydration as well as high selectivity toward the desired product.Further,the novel method demonstrated herein can be employed to other tandem catalytic reactions for sustainable chemical production.
基金financially supported by the Natural Science Foundation of Hebei Province(No.B2015202049)the National Natural Science Foundation of China(Nos.21004017 and 50573018)
文摘Tandem catalytic systems, consisting of ethylene bis（indenyl） zirconium dichloride with two different cocatalysts, alkylaluminum（diethylaluminium chloride or trialkylaluminum） and methylaluminoxane, were employed in preparing branched polyethylene from ethylene as sole monomer. The catalytic system rac-Et（Ind）2Zr Cl2/Al Et2Cl/MAO exhibited high incorporation（29.0/1000C）. The oligomerization and copolymerization reaction conditions in the tandem catalytic system, as well as the different cocatalysts, have effects on the catalytic activity and the properties of the obtained polymer, such as melting temperature, crystallinity, molecular weight and molecular weight distribution. Moreover, the oligomerization reaction condition is the main factor in altering the properties and structures of polyethylene.
文摘Tandem catalysis for the hydrogenation rearrangement of furfural(FA)provides an attractive solution for manufacturing cyclopentanone(CPO)from renewable biomass resources.The Cu-Ni/Al-MCM-41 catalyst was synthesized and afforded excellent catalytic performance with 99.0%conversion and 97.7%selectivity to CPO in a near-neutral solution under 2.0 MPa H2 at 160℃ for 5 h,much higher than those on other molecular sieve supports including MCM-41,SBA-15,HY,and ZSM-5.A small amount of Al highly dispersed in MCM-41 plays an anchoring role and ensures the formation of highly dispersed CuNi bimetallic nanoparticles(NPs).The remarkably improved catalytic performance may be attributed to the bimetallic synergistic and charge transfer effects.In addition,the initial FA concentration and the aqueous system pH required precise control to minimize polymerization and achieve high selectivity of CPO.Fourier transform infrared spectroscopy and mass spectra results indicated that polymerization was sensitive to pH values.Under acidic conditions,FA and intermediate furfuryl alcohol polymerize,while the intermediate 4-hydroxy-2-cyclopentenone mainly polymerizes under alkaline conditions,blocking the cascade of multiple reactions.Therefore,near-neutral conditions are most suitable for minimizing the impact of polymerization.This study provides a useful solution for the current universal problems of polymerization side reactions and low carbon balance for biomass conversion.
基金supported by the National Natural Science Foundation of China(Nos.52302092,22375019)the Beijing Natural Science Foundation(No.2212018)+2 种基金the Beijing Institute of Technology Research Fund Program for Young Scholars(No.2022CX01011)the Fundamental Research Funds for the Central Universities(Nos.2023MS057 and JB 2022004)the Open Research Fund of State Environmental Protection Key Laboratory of Eco-industry,Chinese Research Academy of Environmental Sciences(No.2022KFF-07).
文摘Tandem catalysis,capable of decoupling individual steps,provides a feasible way to build a high-efficiency CO_(2) electro-conversion system for multicarbons(C_(2+)).The construction of electrocatalytic materials is one of focusing issues.Herein,we fabricated a single atom involved multivalent oxide-derived Cu composite material and found it inclined to reconstruct into oxygen-deficient multiphase Cu based species hybridized with monatomic Ni on N doped C matrix.In this prototype,rapid CO generation and C-C coupling are successively achieved on NiN4 sites and surface amorphized Cu species with defects,resembling a micro-production line.In this way,the in situ formed tandem catalyst exhibited a high Faradaic efficiency(FE)of~78%for C_(2+)products along with satisfactory durability over 50 h.Particularly,the reconstruction-induced amorphous layer with abundant asymmetric sites should be favorable to improve the ethanol selectivity(FE:63%),which is about 10 times higher than that of the non-tandem Cu-based contrast material.This work offers a new approach for manipulating tandem catalyst systems towards enhancing C_(2+)products.
文摘Carbon dioxide emissions have increased due to the consumption of fossil fuels,making the neutralization and utilization of CO_(2) a pressing issue.As a clean and efficient energy conversion process,electrocatalytic reduction can reduce carbon dioxide into a series of alcohols and acidic organic molecules,which can effectively realize the utilization and transformation of carbon dioxide.This review focuses on the tuning strategies and structure effects of catalysts for the electrocatalytic CO_(2) reduction reaction(CO_(2)RR).The tuning strategies for the active sites of catalysts have been reviewed from intrinsic and external perspectives.The structure effects for the CO_(2)RR catalysts have also been discussed,such as tandem catalysis,synergistic effects and confinement catalysis.We expect that this review about tuning strategies and structure effects can provide guidance for designing highly efficient CO_(2)RR electrocatalysts.
基金financially supported by Jiangsu Provincial Double-Innovation Doctor Program(No.JSSCBS20210996)。
文摘Heterojunction-based photocatalyst plays an important role in the various heterogeneous catalyses.Z-scheme photocatalytic systems with two semiconductor materials are suitable for harvesting solar energy,while the advanced nanostructuring tools for the fabrication of Z-scheme heterojunction are limited.Here,WO_(3)/MoS_(2)(W/M_(0.2))heterojunction composites were constructed in a microfluidic system with enhanced assembly efficiency,and the photocatalytic performance has been investigated using X-ray photoelectron spectroscopy(XPS),MottSchottky(M-S)analysis and gas chromatograph-mass spectrometer(GC-MS).In addition,in the reduction of nitrobenzene,the photogenerated hole(h^(+))oxidation of formic acid(HCOOH)provides the hydrogen source and the deposited Pd nanoparticles are enriched with photogenerated electrons for improving the transfer hydrogenation efficiency.The microfluidic-prepared tandem photocatalyst gives a meaningful guidance for the design and synthesis of heterojunction catalysts,which is promising for energy maximizing control systems.
基金supported in part by the National Natural Science Foundation of China(Nos.52125103,52071041 and 12074048)the Project for Fundamental and Frontier Research in Chongqing(Nos.cstc2020jcyj-msxmX0777 and cstc2020jcyj-msxmX0796).
文摘Artificial photosynthesis in carbon dioxide(CO_(2))conversion into value-added chemicals attracts considerable attention but suffers from the low activity induced by sluggish separation of photogenerated carriers and the kinetic bottleneck-induced unsatisfied selectivity.Herein,we prepare a new-style Bi/TiO_(2) catalyst formed by pinning bismuth clusters on TiO_(2) nanowires through being confined by pores,which exhibits high activity and selectivity towards photocatalytic production of CH_(4) from CO_(2).Boosted charge transfer from TiO_(2) through Bi to the reactants is revealed via in situ X-ray photon spectroscopy and time-resolved photoluminescence(PL).Further,in situ Fourier transform infrared results confirm that Bi/TiO_(2) not only overcomes the multi-electron kinetics challenge of CO_(2) to CH_(4) via boosting charge transfer,but also facilitates proton production and transfer as well as the intermediates*CHO and*CH_(3)O generation,ultimately achieving the tandem catalysis towards methanation.Theoretical calculation also underlies that the more favorable reaction step from*CO to*CHO on Bi/TiO_(2) results in CH_(4) production with higher selectivity.Our work brings new insights into rational design of photocatalysts with high performance and the formation mechanism of CO_(2) to CH_(4) for solar energy storage in future.
基金the National Natural Science Foundation of China(Nos.22071172 and 52025025)the National Key R&D Prrgram of China(No.2017YFA0204503).
文摘Rational design and synthesis of multimetallic nanostructures(NSs)are fundamentally important for electrochemical CO_(2)reduction reaction(CO_(2)RR).Herein,a multi-step seed-mediated growth method is applied to synthesize asymmetric AuAgCu heterostructures using Au nanobipyramids as nucleation seeds,in which their composition and structures are well controlled.We find that the selectivity of C_(2)products for CO_(2)RR could be effectively regulated by tandem catalysis and electronic effect over trimetallic AuAgCu heterostructures.Particularly,the Faraday efficiency toward ethanol could reach up to 37.5%at a potential of−0.8 V versus reversible hydrogen electrode over asymmetric Au1Ag1Cu5 heterostructures with segregated domains of three constituent metals.This work provides an efficient strategy for the synthesis of multicomponent architectures to boost their promising application in CO_(2)RR.
基金All thanks go to the contributions from all students,postdoctoral fellows,and visiting scholars.Special thanks are extended to the contributions from Prof.Jong Wook Bae(Sungkyunkwan University),Prof.Ruiqin Yang(Zhejiang University of Science and Technology),Prof.Yisheng Tan(Institute of Coal Chemistry,Chinese Academy of Sciences),Prof.Minbo Wu(China University of Petroleum),Prof.Xingang Li(Tianjin University),et al.Jie Yao appreciates the Grant-in-Aid for JSPS Fellows(JSPS KAKENHI 22J11458 and 22KJ1456).
文摘This review provides a comprehensive overview of the distinguished academic career and scientific accomplishments of Prof.Noritatsu Tsubaki at the University of Toyama.For over 35 years,he has dedicated himself to the research field of one-carbon(C1)chemistry,including catalytic conversion of C1 molecules to valuable chemicals and superclean fuels,innovative catalyst and reactor development,and the design of new catalytic reactions and processes.Organized chronologically,this review highlights Prof.Tsubaki’s academic contributions from 1990,when he studied and worked at The University of Tokyo,to his current role as a full professor at the University of Toyama.The academic section of this review is divided into three main parts,focusing on Prof.Tsubaki’s pioneering work in C1 chemistry.We believe that this review will serve as a highly valuable reference for colleagues in the fields of C1 chemistry and catalysis,and inspire the development of more original and groundbreaking research.
基金financially supported by the National Natural Science Foundation of China(Nos.92061110,21925303,21829501,21771186,21222301,21528303,and 21171170)the Anhui Provincial Natural Science Foundation(2108085Y05 and 2108085MB56)+1 种基金Collaborative Innovation Program of Hefei Science Center,CAS(Nos.2020HSCCIP005 and 2022HSC-CIP018)the Hefei National Laboratory for Physical Sciences at the Microscale(KF2020102).
文摘The emergence of metal nanoclusters with atomically precise compositions and structures provides an opportunity for in-depth investigation of catalysis mechanisms and structure−property correlations at the nanoscale.However,a serious problem for metal nanocluster catalysts is that the ligands inhibit the catalytic activity through deactivating the surface of the nanoclusters.Here,we introduce a novel catalytic mode for metal nanoclusters,in which the nanoclusters initiate the catalysis via single electron transfer(SET)without destroying the integrity of nanoclusters,providing a solution for the contradiction between activity and stability of metal nanoclusters.We illustrated that the novel activation mode featured low catalyst loading(0.01 mol%),high TOF,mild reaction conditions,and easy recycling of catalyst in alkyne hydroborylation,which often suffered from poor selectivity,low functional group tolerance,etc.Furthermore,the catalyst[Au_(1)Cu_(14)(TBBT)_(12)(PPh_(3))_(6)]^(+)(TBBTH:p-tert-butylthiophenol)can be applied in highly efficient tandem processes such as hydroborylation−deuteration and hydroborylation−isomerization,demonstrating the utility of the introduced activation mode for metal nanoclusters.
基金supported by the National Key R&D Program of China(2022YFA1504603)the National Natural Science Foundation of China(22372171,22125205,and 22321002)+7 种基金the Fundamental Research Funds for the Central Universities(20720220008)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0600200)the Liaoning Revitalization Talents Program(XLYC2203178)the Liaoning Binhai Laboratory(LBLF-2023-02)the Dalian Institute of Chemical Physics(DICP I202203)the Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy(YLUDNL Fund 2022008)the Yanchang Petroleum Group(yc-hw-2023ky-08)the Photon Science Center for Carbon Neutrality。
文摘Ethylene oxide(EO)and ethylene glycol(EG)are two important commodity chemicals and are industrially produced from petroleum-derived ethylene via thermocatalytic processes.The overoxidation of ethylene and the implementation of high temperature and pressure lead to substantial CO_(2)emission.Renewable energy-driven electrocatalysis provides a low-carbon route for upgrading ethylene under mild conditions,especially when it couples with ethylene electrosynthesis from CO_(2).In this minireview,we summarize recent achievements in the selective electrocatalytic oxidation of ethylene to EO and EG.Three main reaction routes including direct electrocatalytic oxidation with water,indirect electrocatalytic oxidation with halide mediators,and tandem electrocatalytic and thermocatalytic oxidation with hydrogen peroxide intermediate,are discussed.Some representative catalyst systems and reactor designs are exemplified.We discuss the existing scientific and technical challenges of electrocatalytic ethylene upgrading in terms of reaction rate,selectivity,and long-term stability,and propose future research directions and opportunities for pushing the process towards practical application.
基金funded by the National Natural Science Foundation of China (Nos. 21706074 and 21972038)the Natural Science Foundation of Henan Province (No. 2023000410209)+3 种基金the Key Research and Promotion Project of Henan Province (Nos. 202102210261 and 202102310267)the Top-notch Personnel Fund of Henan Agricultural University (No. 30500682)The Science and Technology Research Program of Chongqing Municipal Education Commission (No. KJQN202000519)the foundation project of Chongqing Normal University (No. 18XLB008)
文摘Electrochemical carbon dioxide reduction(CO_(2)RR)plays an important role in solving the problem of high concentration of CO_(2)in the atmosphere and realizing carbon cycle.Core-shell structure has many unique features including tandem catalysis,lattice strain effect,defect engineering,which exhibit great potential in electrocatalysis.In this review,we focus on the advanced core-shell metal-based catalysts(CMCs)for electrochemical CO_(2)RR.The recent progress of CMCs in electrocatalytic CO_(2)RR is described as the follow-ing aspects:(1)The mechanism of electrochemical CO_(2)RR and evaluation parameters of electrocatalyst performance,(2)preparation methods of core-shell metal catalysts and core-shell structural advantages and(3)advanced CMCs towards electrochemical CO_(2)RR.Finally,we make a brief conclusion and propose the opportunities and challenges in the field of electrochemical CO_(2)RR.
