Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical capacity.Toward the broader implementation,the primary obstacle lies in the intricate multi-elec...Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical capacity.Toward the broader implementation,the primary obstacle lies in the intricate multi-electron,multi-step redox reaction associated with sluggish conversion kinetics,subsequently giving rise to a cascade of parasitic issues.In order to smooth reaction kinetics,catalysts are widely introduced to accelerate reaction rate via modulating the energy barrier.Over past decades,a large amount of research has been devoted to the catalyst design and catalytic mechanism exploration,and thus the great progress in electrochemical performance has been realized.Therefore,it is necessary to make a comprehensive review toward key progress in catalyst design and future development pathway.In this review,the basic mechanism of lithium metal batteries is provided along with corresponding advantages and existing challenges detailly described.The main catalysts employed to accelerate cathode reaction with emphasis on their catalytic mechanism are summarized as well.Finally,the rational design and innovative direction toward efficient catalysts are suggested for future application in metal-sulfur/gas battery and beyond.This review is expected to drive and benefit future research on rational catalyst design with multi-parameter synergistic impacts on the activity and stability of next-generation metal battery,thus opening new avenue for sustainable solution to climate change,energy and environmental issues,and the potential industrial economy.展开更多
An efficient and direct procedure has been developed for the preparation of amidoalkyl naphthols by a one-pot condensation of aryl aldehydes, 2-naphthol and urea or amides, in the presence of HClO4-SiO2 as a heterogen...An efficient and direct procedure has been developed for the preparation of amidoalkyl naphthols by a one-pot condensation of aryl aldehydes, 2-naphthol and urea or amides, in the presence of HClO4-SiO2 as a heterogeneous catalyst. The reactions were carried out under reflux and solvent-free conditions. The present methodology offers several advantages such as excellent yields, simple procedure, easy work-up and ecofriendly reaction condition. The catalyst is easily prepared, stable, reusable and efficient under the reaction conditions.展开更多
A double active center system, namely Salen-Cu(Ⅱ)@MIL-101(Cr), was successfully synthesized via the"ship in a bottle" approach, which acted as a bifunctional material for both capture and conversion of ...A double active center system, namely Salen-Cu(Ⅱ)@MIL-101(Cr), was successfully synthesized via the"ship in a bottle" approach, which acted as a bifunctional material for both capture and conversion of COin a single process. For the first time, Salen-Cu(Ⅱ)@MIL-101(Cr) catalyst was developed for the synthesis of propylene carbonate from COand propylene oxide under room temperature and ambient pressure with a yield of 87.8% over 60 h. Furthermore, the reaction mechanism was also discussed.展开更多
Safe, sustainable, and green production of hydro gen peroxide is an exciting proposition due to the role of hydrogen peroxide as a green oxidant and energy carrier for fuel cells. The current work reports the developm...Safe, sustainable, and green production of hydro gen peroxide is an exciting proposition due to the role of hydrogen peroxide as a green oxidant and energy carrier for fuel cells. The current work reports the development of carbon dot-impregnated waterborne hyperbranched polyurethane as a heterogeneous photo-catalyst for solar-driven production of hydrogen peroxide. The results reveal that the carbon dots possess a suitable band-gap of 2.98 eV,which facilitates effective splitting of both water and ethanol under solar irradiation. Inclusion of the carbon dots within the eco-friendly polymeric material ensures their catalytic activity and also provides a facile route for easy catalyst separation, especially from a solubilizing medium.The overall process was performed in accordance with the principles of green chemistry using bio-based precursorsand aqueous medium. This work highlights the potential of carbon dots as an effective photo-catalyst.展开更多
catalyst for the synthesis of 14-aryl- 14-H-dibenzo[aj]xanthenes Silica supported ammonium dihydrogen phosphate (NH4H2PO4/SiO2) is found to be a recyclable heterogeneous catalyst for a rapid and efficient synthesis ...catalyst for the synthesis of 14-aryl- 14-H-dibenzo[aj]xanthenes Silica supported ammonium dihydrogen phosphate (NH4H2PO4/SiO2) is found to be a recyclable heterogeneous catalyst for a rapid and efficient synthesis of various aryl-14-H-dibenzo[a,j]xanthenes with excellent yields under solvent-free conditions. The present methodology offers several advantages such as excellent yields, simple procedure, short reaction times and milder conditions. 2009 Shahnaz Rostamizadeh. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
Co-salen functionalized on graphene with an average pore size of 27.7 nm as a heterogeneous catalyst exhibited good catalytic activity and recyclability in cyclohexene oxidation.
A cheap and recyclable ZnO-beta zeolite was used as catalyst for the synthesis of benzothiazole derivatives.This method provides several advantages such as environmental friendliness,short reaction times,high yields,s...A cheap and recyclable ZnO-beta zeolite was used as catalyst for the synthesis of benzothiazole derivatives.This method provides several advantages such as environmental friendliness,short reaction times,high yields,simple work-up procedure and catalyst was successfully reused for four cycles without significant loss of activity.展开更多
A novel Zn-based metal–organic framework Zn(dobdc)(datz)[Zn_(2)(H2dobdc)(datz)2$1.5DMF]with plentiful hydrogen bond donors(HBD)groups was facilely synthesized from mixed ligands.The dual activation of metal Zn sites ...A novel Zn-based metal–organic framework Zn(dobdc)(datz)[Zn_(2)(H2dobdc)(datz)2$1.5DMF]with plentiful hydrogen bond donors(HBD)groups was facilely synthesized from mixed ligands.The dual activation of metal Zn sites and HBD groups for epoxides by forming Zn–O adduct and hydrogen bonds facilitated the ring-opening of epoxide substrate,which is critical for the subsequent CO_(2) fixation.Also,the existence of micropores and N-rich units in Zn(dobdc)(datz)afforded affinity towards CO_(2),which is beneficial to further improvement on catalytic CO_(2) conversion performance.Satisfactorily,Zn(dobdc)(datz)/Bu4NBr system was proved efficient heterogeneous catalyst for the CO_(2) cycloaddition with epoxides,and 98%propylene carbonate yield was obtained under mild conditions(80C,1.5 MPa and solvent-free).In addition,Zn(dobdc)(datz)/Bu4NBr exhibited remarkable versatility to different epoxides and could be completely recycled over six runs with high catalytic activity.The highly stable,easily recycle and solvent-free Zn-based MOF reported here displays eco-friendly and efficient performance to CO_(2)conversion.展开更多
Solar light-driven CO_(2)reduction to high value-added chemicals has considered as an outstanding way to solve energy crisis and climate warming.Recently,various photocatalysts have been developed to achieve this reac...Solar light-driven CO_(2)reduction to high value-added chemicals has considered as an outstanding way to solve energy crisis and climate warming.Recently,various photocatalysts have been developed to achieve this reaction.Among them,cobaltbased heterogeneous catalysts have attracted great interest because of their promising performance,product selectivity and stability.Herein,we systematically summarize the research progress of various cobalt-based heterogeneous catalysts for the photoreduction of CO_(2),such as single-atom cobalt,and cobalt-based oxides,nitrides,sulfi des,phosphides,metal-organic frameworks and covalent-organic frameworks.Meanwhile,the advantages and structure-activity relationship of these catalysts in photocatalytic CO_(2)reduction reaction are discussed.Finally,the challenges and prospects for constructing cobaltbased heterogeneous catalysts with high effi ciency are highlighted.展开更多
The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving c...The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving carbon neutrality is the utilization of CO_(2) under economic and sustainable conditions.Recently,the strong need for carbon neutrality has led to a proliferation of studies on the direct conversion of CO_(2) into carboxylic acids,which can effectively alleviate CO_(2) emissions and create high-value chemicals.The purpose of this review is to present the application prospects of carboxylic acids and the basic principles of CO_(2) conversion into carboxylic acids through photo-,electric-,and thermal catalysis.Special attention is focused on the regulation strategy of the activity of abundant catalysts at the molecular level,inspiring the preparation of high-performance catalysts.In addition,theoretical calculations,advanced technologies,and numerous typical examples are introduced to elaborate on the corresponding process and influencing factors of catalytic activity.Finally,challenges and prospects are provided for the future development of this field.It is hoped that this review will contribute to a deeper understanding of the conversion of CO_(2) into carboxylic acids and inspire more innovative breakthroughs.展开更多
Chemical fixation of carbon dioxide(CO_(2))is an energy-saving method for alleviating the greenhouse gas emissions,whereas it persists a challenge posed by the demand for efficient catalysts.Herein,four unprecedented ...Chemical fixation of carbon dioxide(CO_(2))is an energy-saving method for alleviating the greenhouse gas emissions,whereas it persists a challenge posed by the demand for efficient catalysts.Herein,four unprecedented examples of tetradecanuclear vanadium clusters,namely,[(C_(2)H_(8)N_(2))6(CH_(3)O)8(CH_(3)OH)_(2)V_(10)^(Ⅳ)V_(4)ⅤO_(26)](V_(14)-1),[(C_(3)H_(10)N_(2))_(6)(CH_(3)O)_(8)(CH_(3)OH)_(2)V_(10)^(Ⅳ)V_(4)ⅤO_(26)](V14^(-2)),[(C_(6)H_(14)N_(2))6(CH_(3)O)8(CH_(3)OH)_(2)V_(10)^(Ⅳ)V_(4)ⅤO_(26)]·5H_(2)O(V14^(-3))and[(C_(4)H_(12)N_(2)O)_(4)(C_(4)H_(11)N_(2)O)_(2)(CH_(3)O)_(2)V_(10)^(Ⅳ)V_(4)ⅤO_(28)]·6H_(2)O(V_(14)-4),have been triumphantly designed and constructed under solvothermal conditions.Among them,compounds V_(14)-1–4 are the first cases of tetradecanuclear vanadium clusters without the introduction of inorganic acid radical ions.Two main units[V_(10)^(Ⅳ)V_(4)ⅤO_(26)]8+and[V10ⅣV4ⅤO28]4+represent brand-new configurations of tetradecanuclear vanadium clusters.Given the fact that the presence of V^(Ⅳ)/V^(Ⅴ)can potentially facilitate electron transfer and consequently expedite catalytic reactions,we explored the catalytic activities of these compounds.Remarkably,V_(14)-1 was further used as a heterogeneous catalyst in the CO_(2)fixation into cyclic carbonates under milder conditions(60℃,0.5 MPa)and exhibited higher catalytic activity.Also,the experimental results indicated that V_(14)-1 could efficiently catalyze the sulfoxidation,which could fully convert most sulfides within 40 min at room temperature.Moreover,as a stable heterogeneous catalyst employed in CO_(2)fixation with epoxides and oxidation of sulfides,V_(14)-1 could be consecutively used multiple cycles without losing its catalytic activity.展开更多
Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch ...Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch procedure and continuous-flow procedure) were used to study the variations of reaction processing. The heterogeneous catalysts presented excellent reactivity and recyclability for iodobenzene and bromobenzene substrates in batch mode, which can be attributed to stabilization of Pd nanoparticles by the thiol and amino groups on the AC supports. However, significant dehalogenation in the reaction mixture and Pd leaching from the heterogeneous catalysts were observed in continuous-flow mode.This unique phenomenon in continuous-flow mode resulted in a dramatic decline in reaction selectivity and durability of heterogeneous catalysts comparing with that of batch mode. In addition, the heterogeneous Pd catalysts with thiol-and amino-modified AC supports exhibited different reactivity and durability in batch and continuous-flow mode owing to the difference of interaction between Pd species and AC supports.展开更多
Composites incorporating nanoparticles (NPs) within metal-organic frameworks (MOFs) find applications in many different fields.In particular,using MOF layers as molecular sieves built on the NPs could enable selec...Composites incorporating nanoparticles (NPs) within metal-organic frameworks (MOFs) find applications in many different fields.In particular,using MOF layers as molecular sieves built on the NPs could enable selectivity in heterogeneous catalysis.However,such composites typically exhibit low catalytic efficiency,due to the slow diffusion of the reactants in the long and narrow channels of the MOF shell.In order to improve the catalytic efficiency of these systems,here we report the fabrication of NPs incorporated in nanosized MOFs (NPs@nano-MOFs),obtained by reducing the size of the MOF crystals grown around the NPs.The crystal size of the composites was controlled by modulating the nucleation rate of the MOFs during the encapsulation of pre-synthesized and catalytically active NPs;in this way,NPs@MOF crystals smaller than 50 nm were synthesized and subsequently used as highly efficient catalysts.Due to the shorter path from the MOF surface to the active sites,the obtained Pt@nano-MOFs composites showed a higher conversion rate than their larger-sized counterparts in the synthesis of imines via cascade reaction of nitrobenzene and in the hydrogenation of olefins,while retaining the excellent size and shape selectivity associated with the molecular sieving effect of the MOF layer.The present strategy can also be applied to prepare other encapsulated nanostructures combining various types of NPs and nano-MOFs,thus highlighting the broad potential of this approach for developing optimized catalysts with high reactivity and selectivity.展开更多
TiO_2 nanoparticles(TiO_2 NPs) worked as an efficient heterogeneous catalyst in a one-pot,three-component,and solvent free Mannich reaction;producing variousβ-aminocarbonyls in good yields,and with good stereoselec...TiO_2 nanoparticles(TiO_2 NPs) worked as an efficient heterogeneous catalyst in a one-pot,three-component,and solvent free Mannich reaction;producing variousβ-aminocarbonyls in good yields,and with good stereoselectivities.The catalyst was easily separated from the reaction mixture and was recycled four times with no significant loss of its catalytic activity.展开更多
The catalytic activity ofβ-cyclodextrin immobilized on Dowex resin as an efficient solid-liquid phase transfer catalyst was developed for the synthesis of alkyl thiocyanates and phenacyl derivatives in water. The nuc...The catalytic activity ofβ-cyclodextrin immobilized on Dowex resin as an efficient solid-liquid phase transfer catalyst was developed for the synthesis of alkyl thiocyanates and phenacyl derivatives in water. The nucleophilic substitution reactions were performed under mild reaction condition and gave the products in excellent yields. Fur thermore, the catalyst could be recycled by facile separation without any loss of activity.展开更多
Functional materials are widely used in chemical industry in order to reduce the process cost while simultaneously increase the product quality.Considering their significant effects,systematic methods for the optimal ...Functional materials are widely used in chemical industry in order to reduce the process cost while simultaneously increase the product quality.Considering their significant effects,systematic methods for the optimal selection and design of materials are essential.The conventional synthesis-and-test method for materials development is inefficient and costly.Additionally,the performance of the resulting materials is usually limited by the designer’s expertise.During the past few decades,computational methods have been significantly developed and they now become a very important tool for the optimal design of functional materials for various chemical processes.This article selectively focuses on two important process functional materials,namely heterogeneous catalyst and gas separation agent.Theoretical methods and representative works for computational screening and design of these materials are reviewed.展开更多
Reusable solid fluorination reagents and heterogeneous catalysts are ideally suited for late-stage fluorination with fast and clean conversion and simplified work-up.Here we report Pd-functionalized two-dimensional me...Reusable solid fluorination reagents and heterogeneous catalysts are ideally suited for late-stage fluorination with fast and clean conversion and simplified work-up.Here we report Pd-functionalized two-dimensional metal-organic layers(MOLs)as solid reagents and heterogeneous catalysts to efficiently fluorinate a broad scope of aromatic compounds.Site isolation in the MOLs provides a unique opportunity to stabilize highly active F-containing species for the chemical conversion.A terpyridine(TPY)-based ligand on the MOL,together with a 2-chloro-1,10-phenanthroline(phenCl)as a co-ligand,chelates Pd^(Ⅱ)toform a reactive center.After treatment with Selectfluor/H_(2)0,an(N-fluoroxy)-(2-chloro)-phenanthrolinium[N-(FO)-phenCl^(+)]moiety is produced from the co-ligand on the Pd center.This active species serves as a stochiometric solid fluorination reagent,which shows different regioselectivities and reactivities as compared to homogeneous catalysts that involves Pd^(Ⅲ/Ⅳ)-F intermediates in catalytic cycles.The MOLs can also be used as heterogeneous catalysts for fluorination using Selectfluor.This work highlights opportunities in using MOLs to stabilize unique active sites for late-stage fluorination.展开更多
Fe(HSO4)3 has been used as an efficient and recyclable catalyst for the one-pot synthesis of 14-aryl- or alkyl-14Hdibenzo[aj]xanthene derivatives by the reaction of 2-naphtol and aldehydes. Different types of aromat...Fe(HSO4)3 has been used as an efficient and recyclable catalyst for the one-pot synthesis of 14-aryl- or alkyl-14Hdibenzo[aj]xanthene derivatives by the reaction of 2-naphtol and aldehydes. Different types of aromatic and aliphatic aldehydes are used in the reaction and in all cases the products were obtained in good to excellent yields.展开更多
A Pt/γ-Al2O3-C heterogeneous catalyst with improved catalytic performance was successfully prepared. Bayberry talmin(BT), an abundant natural plant polyphenol, was utilized to modifiy the surface of the Pt/γ-Al2O3...A Pt/γ-Al2O3-C heterogeneous catalyst with improved catalytic performance was successfully prepared. Bayberry talmin(BT), an abundant natural plant polyphenol, was utilized to modifiy the surface of the Pt/γ-Al2O3 matrix and then stabilize Pt nanoparticles(NPs). The catalyst was systematically and specifically characterized by a collec- tion of analytic tools including XRD, XPS, FTIR, TEM, and TG. It was found that the Pt NPs were envenly dispered on the γ-Al2O3-C matrix. Meanwhile, when the catalyst was applied for selective hydrogenation of cilmamalde- hyde(CMA) in the presence of KOH promoter in solvent, excellent catalytic performance was obtained. The selecti- vity to cinnamyl alcohol(CMO) reached 97.88% with 88.45% CMA conversion within 30 min in the presence of 0.037 mol/L KOH, without significant loss of catalytic activity even under cyclic measurements for 5 times. The excelleut catalytic performances should be ascribed predominantly to the uniform and stable dispersion ofPt NPs on the γ-Al2O3-C matrix and the excellent heat stability of BT.展开更多
α, α'-Benzylidene bis(4-hydroxycoumarin) derivatives were readily prepared in a few minutes with good yields through the reaction of an aromatic aldehyde and 4-hydroxycoumarin in aqueous media in the presence of ...α, α'-Benzylidene bis(4-hydroxycoumarin) derivatives were readily prepared in a few minutes with good yields through the reaction of an aromatic aldehyde and 4-hydroxycoumarin in aqueous media in the presence of catalytic tris(hydrogensulfato) boron [B(HSO_4)_3].展开更多
基金supported by the National Natural Science Foundation of China(52272194)Liaoning Revitalization Talents Program(XLYC2007155)。
文摘Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical capacity.Toward the broader implementation,the primary obstacle lies in the intricate multi-electron,multi-step redox reaction associated with sluggish conversion kinetics,subsequently giving rise to a cascade of parasitic issues.In order to smooth reaction kinetics,catalysts are widely introduced to accelerate reaction rate via modulating the energy barrier.Over past decades,a large amount of research has been devoted to the catalyst design and catalytic mechanism exploration,and thus the great progress in electrochemical performance has been realized.Therefore,it is necessary to make a comprehensive review toward key progress in catalyst design and future development pathway.In this review,the basic mechanism of lithium metal batteries is provided along with corresponding advantages and existing challenges detailly described.The main catalysts employed to accelerate cathode reaction with emphasis on their catalytic mechanism are summarized as well.Finally,the rational design and innovative direction toward efficient catalysts are suggested for future application in metal-sulfur/gas battery and beyond.This review is expected to drive and benefit future research on rational catalyst design with multi-parameter synergistic impacts on the activity and stability of next-generation metal battery,thus opening new avenue for sustainable solution to climate change,energy and environmental issues,and the potential industrial economy.
文摘An efficient and direct procedure has been developed for the preparation of amidoalkyl naphthols by a one-pot condensation of aryl aldehydes, 2-naphthol and urea or amides, in the presence of HClO4-SiO2 as a heterogeneous catalyst. The reactions were carried out under reflux and solvent-free conditions. The present methodology offers several advantages such as excellent yields, simple procedure, easy work-up and ecofriendly reaction condition. The catalyst is easily prepared, stable, reusable and efficient under the reaction conditions.
基金supported by the National Key Projects for Fundamental R&D Program of China(2016YFB0600902)the NFSC of Tianjin(16JCZDJC36700 and 14JCQNJC03000)
文摘A double active center system, namely Salen-Cu(Ⅱ)@MIL-101(Cr), was successfully synthesized via the"ship in a bottle" approach, which acted as a bifunctional material for both capture and conversion of COin a single process. For the first time, Salen-Cu(Ⅱ)@MIL-101(Cr) catalyst was developed for the synthesis of propylene carbonate from COand propylene oxide under room temperature and ambient pressure with a yield of 87.8% over 60 h. Furthermore, the reaction mechanism was also discussed.
基金DBT(Grant No.BT/235/NE/TBP/2011 Dated April 30,2012),India,for financial support
文摘Safe, sustainable, and green production of hydro gen peroxide is an exciting proposition due to the role of hydrogen peroxide as a green oxidant and energy carrier for fuel cells. The current work reports the development of carbon dot-impregnated waterborne hyperbranched polyurethane as a heterogeneous photo-catalyst for solar-driven production of hydrogen peroxide. The results reveal that the carbon dots possess a suitable band-gap of 2.98 eV,which facilitates effective splitting of both water and ethanol under solar irradiation. Inclusion of the carbon dots within the eco-friendly polymeric material ensures their catalytic activity and also provides a facile route for easy catalyst separation, especially from a solubilizing medium.The overall process was performed in accordance with the principles of green chemistry using bio-based precursorsand aqueous medium. This work highlights the potential of carbon dots as an effective photo-catalyst.
文摘catalyst for the synthesis of 14-aryl- 14-H-dibenzo[aj]xanthenes Silica supported ammonium dihydrogen phosphate (NH4H2PO4/SiO2) is found to be a recyclable heterogeneous catalyst for a rapid and efficient synthesis of various aryl-14-H-dibenzo[a,j]xanthenes with excellent yields under solvent-free conditions. The present methodology offers several advantages such as excellent yields, simple procedure, short reaction times and milder conditions. 2009 Shahnaz Rostamizadeh. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
基金the National Natural Science Foundation of China(20973079 and U1162201)Graduate Innovation Fund of Jilin University(20121051)
文摘Co-salen functionalized on graphene with an average pore size of 27.7 nm as a heterogeneous catalyst exhibited good catalytic activity and recyclability in cyclohexene oxidation.
文摘A cheap and recyclable ZnO-beta zeolite was used as catalyst for the synthesis of benzothiazole derivatives.This method provides several advantages such as environmental friendliness,short reaction times,high yields,simple work-up procedure and catalyst was successfully reused for four cycles without significant loss of activity.
基金the National Natural Science Foundation of China(21972034,21673060)the State Key Lab of Urban Water Resource and Environment of Harbin Institute of Technology(HIT2019DX12).
文摘A novel Zn-based metal–organic framework Zn(dobdc)(datz)[Zn_(2)(H2dobdc)(datz)2$1.5DMF]with plentiful hydrogen bond donors(HBD)groups was facilely synthesized from mixed ligands.The dual activation of metal Zn sites and HBD groups for epoxides by forming Zn–O adduct and hydrogen bonds facilitated the ring-opening of epoxide substrate,which is critical for the subsequent CO_(2) fixation.Also,the existence of micropores and N-rich units in Zn(dobdc)(datz)afforded affinity towards CO_(2),which is beneficial to further improvement on catalytic CO_(2) conversion performance.Satisfactorily,Zn(dobdc)(datz)/Bu4NBr system was proved efficient heterogeneous catalyst for the CO_(2) cycloaddition with epoxides,and 98%propylene carbonate yield was obtained under mild conditions(80C,1.5 MPa and solvent-free).In addition,Zn(dobdc)(datz)/Bu4NBr exhibited remarkable versatility to different epoxides and could be completely recycled over six runs with high catalytic activity.The highly stable,easily recycle and solvent-free Zn-based MOF reported here displays eco-friendly and efficient performance to CO_(2)conversion.
基金supported by National Key R&D Program of China(2022YFA1502902,2017YFA0700104)the National Natural Science Foundation of China(22271218,22071182,22001043,21931007)+1 种基金the 111 Project of China(D17003)the Science&Technology Development Fund of Tianjin Education Commission for Higher Education(2018KJ129).
文摘Solar light-driven CO_(2)reduction to high value-added chemicals has considered as an outstanding way to solve energy crisis and climate warming.Recently,various photocatalysts have been developed to achieve this reaction.Among them,cobaltbased heterogeneous catalysts have attracted great interest because of their promising performance,product selectivity and stability.Herein,we systematically summarize the research progress of various cobalt-based heterogeneous catalysts for the photoreduction of CO_(2),such as single-atom cobalt,and cobalt-based oxides,nitrides,sulfi des,phosphides,metal-organic frameworks and covalent-organic frameworks.Meanwhile,the advantages and structure-activity relationship of these catalysts in photocatalytic CO_(2)reduction reaction are discussed.Finally,the challenges and prospects for constructing cobaltbased heterogeneous catalysts with high effi ciency are highlighted.
基金financial support from the King Abdullah University of Science and Technology(KAUST).
文摘The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving carbon neutrality is the utilization of CO_(2) under economic and sustainable conditions.Recently,the strong need for carbon neutrality has led to a proliferation of studies on the direct conversion of CO_(2) into carboxylic acids,which can effectively alleviate CO_(2) emissions and create high-value chemicals.The purpose of this review is to present the application prospects of carboxylic acids and the basic principles of CO_(2) conversion into carboxylic acids through photo-,electric-,and thermal catalysis.Special attention is focused on the regulation strategy of the activity of abundant catalysts at the molecular level,inspiring the preparation of high-performance catalysts.In addition,theoretical calculations,advanced technologies,and numerous typical examples are introduced to elaborate on the corresponding process and influencing factors of catalytic activity.Finally,challenges and prospects are provided for the future development of this field.It is hoped that this review will contribute to a deeper understanding of the conversion of CO_(2) into carboxylic acids and inspire more innovative breakthroughs.
基金supported by the Natural Science Foundation of Jiangsu(BK20191359)the National Natural Science Foundation of China(92161109)+1 种基金the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX22_1343)the Social Science Foundation of Jiangsu(19TQB002)。
文摘Chemical fixation of carbon dioxide(CO_(2))is an energy-saving method for alleviating the greenhouse gas emissions,whereas it persists a challenge posed by the demand for efficient catalysts.Herein,four unprecedented examples of tetradecanuclear vanadium clusters,namely,[(C_(2)H_(8)N_(2))6(CH_(3)O)8(CH_(3)OH)_(2)V_(10)^(Ⅳ)V_(4)ⅤO_(26)](V_(14)-1),[(C_(3)H_(10)N_(2))_(6)(CH_(3)O)_(8)(CH_(3)OH)_(2)V_(10)^(Ⅳ)V_(4)ⅤO_(26)](V14^(-2)),[(C_(6)H_(14)N_(2))6(CH_(3)O)8(CH_(3)OH)_(2)V_(10)^(Ⅳ)V_(4)ⅤO_(26)]·5H_(2)O(V14^(-3))and[(C_(4)H_(12)N_(2)O)_(4)(C_(4)H_(11)N_(2)O)_(2)(CH_(3)O)_(2)V_(10)^(Ⅳ)V_(4)ⅤO_(28)]·6H_(2)O(V_(14)-4),have been triumphantly designed and constructed under solvothermal conditions.Among them,compounds V_(14)-1–4 are the first cases of tetradecanuclear vanadium clusters without the introduction of inorganic acid radical ions.Two main units[V_(10)^(Ⅳ)V_(4)ⅤO_(26)]8+and[V10ⅣV4ⅤO28]4+represent brand-new configurations of tetradecanuclear vanadium clusters.Given the fact that the presence of V^(Ⅳ)/V^(Ⅴ)can potentially facilitate electron transfer and consequently expedite catalytic reactions,we explored the catalytic activities of these compounds.Remarkably,V_(14)-1 was further used as a heterogeneous catalyst in the CO_(2)fixation into cyclic carbonates under milder conditions(60℃,0.5 MPa)and exhibited higher catalytic activity.Also,the experimental results indicated that V_(14)-1 could efficiently catalyze the sulfoxidation,which could fully convert most sulfides within 40 min at room temperature.Moreover,as a stable heterogeneous catalyst employed in CO_(2)fixation with epoxides and oxidation of sulfides,V_(14)-1 could be consecutively used multiple cycles without losing its catalytic activity.
基金the support of the National Natural Science Foundation of China (20222809, 21978146)TsinghuaFoshan Innovation Special Fund (2021THFS0214)。
文摘Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch procedure and continuous-flow procedure) were used to study the variations of reaction processing. The heterogeneous catalysts presented excellent reactivity and recyclability for iodobenzene and bromobenzene substrates in batch mode, which can be attributed to stabilization of Pd nanoparticles by the thiol and amino groups on the AC supports. However, significant dehalogenation in the reaction mixture and Pd leaching from the heterogeneous catalysts were observed in continuous-flow mode.This unique phenomenon in continuous-flow mode resulted in a dramatic decline in reaction selectivity and durability of heterogeneous catalysts comparing with that of batch mode. In addition, the heterogeneous Pd catalysts with thiol-and amino-modified AC supports exhibited different reactivity and durability in batch and continuous-flow mode owing to the difference of interaction between Pd species and AC supports.
基金This work was financially supported by the National Natural Science Foundation of China (Nos. 21641005 and 21604038), the Beijing Engineering Center for Hierarchical Catalysts, the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT1205), the Jiangsu Provindal Founds for Natural Science Foundation (No. BK20160975), the Program for Outstanding Young Scholars from the Organization Department of the CPC Central Committee, and the National Basic Research Program of China (973 Program) (Nos. 2014CB932104 and 2015CB932200).
文摘Composites incorporating nanoparticles (NPs) within metal-organic frameworks (MOFs) find applications in many different fields.In particular,using MOF layers as molecular sieves built on the NPs could enable selectivity in heterogeneous catalysis.However,such composites typically exhibit low catalytic efficiency,due to the slow diffusion of the reactants in the long and narrow channels of the MOF shell.In order to improve the catalytic efficiency of these systems,here we report the fabrication of NPs incorporated in nanosized MOFs (NPs@nano-MOFs),obtained by reducing the size of the MOF crystals grown around the NPs.The crystal size of the composites was controlled by modulating the nucleation rate of the MOFs during the encapsulation of pre-synthesized and catalytically active NPs;in this way,NPs@MOF crystals smaller than 50 nm were synthesized and subsequently used as highly efficient catalysts.Due to the shorter path from the MOF surface to the active sites,the obtained Pt@nano-MOFs composites showed a higher conversion rate than their larger-sized counterparts in the synthesis of imines via cascade reaction of nitrobenzene and in the hydrogenation of olefins,while retaining the excellent size and shape selectivity associated with the molecular sieving effect of the MOF layer.The present strategy can also be applied to prepare other encapsulated nanostructures combining various types of NPs and nano-MOFs,thus highlighting the broad potential of this approach for developing optimized catalysts with high reactivity and selectivity.
文摘TiO_2 nanoparticles(TiO_2 NPs) worked as an efficient heterogeneous catalyst in a one-pot,three-component,and solvent free Mannich reaction;producing variousβ-aminocarbonyls in good yields,and with good stereoselectivities.The catalyst was easily separated from the reaction mixture and was recycled four times with no significant loss of its catalytic activity.
文摘The catalytic activity ofβ-cyclodextrin immobilized on Dowex resin as an efficient solid-liquid phase transfer catalyst was developed for the synthesis of alkyl thiocyanates and phenacyl derivatives in water. The nucleophilic substitution reactions were performed under mild reaction condition and gave the products in excellent yields. Fur thermore, the catalyst could be recycled by facile separation without any loss of activity.
文摘Functional materials are widely used in chemical industry in order to reduce the process cost while simultaneously increase the product quality.Considering their significant effects,systematic methods for the optimal selection and design of materials are essential.The conventional synthesis-and-test method for materials development is inefficient and costly.Additionally,the performance of the resulting materials is usually limited by the designer’s expertise.During the past few decades,computational methods have been significantly developed and they now become a very important tool for the optimal design of functional materials for various chemical processes.This article selectively focuses on two important process functional materials,namely heterogeneous catalyst and gas separation agent.Theoretical methods and representative works for computational screening and design of these materials are reviewed.
基金the National Natural Science Foundation of China(NSFC)(Nos.21671162,21721001)the Ministry of Science and Technology of China(No.2016YFA0200702).
文摘Reusable solid fluorination reagents and heterogeneous catalysts are ideally suited for late-stage fluorination with fast and clean conversion and simplified work-up.Here we report Pd-functionalized two-dimensional metal-organic layers(MOLs)as solid reagents and heterogeneous catalysts to efficiently fluorinate a broad scope of aromatic compounds.Site isolation in the MOLs provides a unique opportunity to stabilize highly active F-containing species for the chemical conversion.A terpyridine(TPY)-based ligand on the MOL,together with a 2-chloro-1,10-phenanthroline(phenCl)as a co-ligand,chelates Pd^(Ⅱ)toform a reactive center.After treatment with Selectfluor/H_(2)0,an(N-fluoroxy)-(2-chloro)-phenanthrolinium[N-(FO)-phenCl^(+)]moiety is produced from the co-ligand on the Pd center.This active species serves as a stochiometric solid fluorination reagent,which shows different regioselectivities and reactivities as compared to homogeneous catalysts that involves Pd^(Ⅲ/Ⅳ)-F intermediates in catalytic cycles.The MOLs can also be used as heterogeneous catalysts for fluorination using Selectfluor.This work highlights opportunities in using MOLs to stabilize unique active sites for late-stage fluorination.
文摘Fe(HSO4)3 has been used as an efficient and recyclable catalyst for the one-pot synthesis of 14-aryl- or alkyl-14Hdibenzo[aj]xanthene derivatives by the reaction of 2-naphtol and aldehydes. Different types of aromatic and aliphatic aldehydes are used in the reaction and in all cases the products were obtained in good to excellent yields.
基金Supported by the National Natural Science Foundation of China(No. 51173122), the Foundation of the Education Department of Sichnan Province, China(No. 16ZA0049) and the Foundation of the Science and Technology Commission of Sichuan Province, China(No.2016JY0259).
文摘A Pt/γ-Al2O3-C heterogeneous catalyst with improved catalytic performance was successfully prepared. Bayberry talmin(BT), an abundant natural plant polyphenol, was utilized to modifiy the surface of the Pt/γ-Al2O3 matrix and then stabilize Pt nanoparticles(NPs). The catalyst was systematically and specifically characterized by a collec- tion of analytic tools including XRD, XPS, FTIR, TEM, and TG. It was found that the Pt NPs were envenly dispered on the γ-Al2O3-C matrix. Meanwhile, when the catalyst was applied for selective hydrogenation of cilmamalde- hyde(CMA) in the presence of KOH promoter in solvent, excellent catalytic performance was obtained. The selecti- vity to cinnamyl alcohol(CMO) reached 97.88% with 88.45% CMA conversion within 30 min in the presence of 0.037 mol/L KOH, without significant loss of catalytic activity even under cyclic measurements for 5 times. The excelleut catalytic performances should be ascribed predominantly to the uniform and stable dispersion ofPt NPs on the γ-Al2O3-C matrix and the excellent heat stability of BT.
文摘α, α'-Benzylidene bis(4-hydroxycoumarin) derivatives were readily prepared in a few minutes with good yields through the reaction of an aromatic aldehyde and 4-hydroxycoumarin in aqueous media in the presence of catalytic tris(hydrogensulfato) boron [B(HSO_4)_3].