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
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
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
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
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
Being a typical state of the art heterogeneous catalyst,supported noble metal catalyst often demonstrates enhanced catalytic properties.However,a facile synthetic method for realizing large-scale and low-cost supporte...Being a typical state of the art heterogeneous catalyst,supported noble metal catalyst often demonstrates enhanced catalytic properties.However,a facile synthetic method for realizing large-scale and low-cost supported noble metal catalyst is strictly indispensable.To this end,by making use of the strong metal-support interaction(SMSI)and mechanochemical reaction,we introduce an efficient synthetic route to obtain ultrafine Pt and Ir nanoclusters immobilized on diverse substrates by wet chemical milling.We further demonstrate the scaling-up effect of our approach by large-scale ball-milling production of Pt nanoclusters immobilized on TiO_(2)substrate.The synthesized Pt/Ir@Co_(3)O_(4)catalysts exhibit superior oxygen evolution reaction(OER)performance with only 230 and 290 mV overpotential to achieve current density of 10 and 100 mA·cm^(-2),beating the catalytic performance of Co_(3)O_(4)supported Pt or Ir clusters and commercial Ir/C.It is envisioned that the present work strategically directs facile ways for fabricating supported noble metal heterogeneous catalysts.展开更多
Main observation and conclusion We describe a practical and general protocol for immobilization of heterogeneous catalysts to mechanically robust porous ultra-high molecular weight polyethylene tablets using inter-fac...Main observation and conclusion We describe a practical and general protocol for immobilization of heterogeneous catalysts to mechanically robust porous ultra-high molecular weight polyethylene tablets using inter-facial Lifshitz-van der Waals Interactions.Diverse types of powderous catalysts,including Cu,Pd/C,Pd/Al2O3,Pt/C,and Rh/C have been immobilized successfully.The immobilized catalysts are mechanistically robust towards stirring in solutions,and they worked well in diverse synthetic reactions.The immobilized catalyst tablets are easy to handle and reused.Moreover,the metal leaching of immobilized catalysts was reduced significantly.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
The discharge of the antibiotic wastewater has increased dramatically in our country with the development of medical science and wide application of antibiotic,resulting in serious harm to human body and ecological en...The discharge of the antibiotic wastewater has increased dramatically in our country with the development of medical science and wide application of antibiotic,resulting in serious harm to human body and ecological environment.In this work,ciprofloxacin(CIP)was selected as one of typical antibiotics and heterogeneous Fenton-like catalysts were prepared for the treatment of ciprofloxacin wastewater.The sodium alginate(SA)gel microspheres catalysts were prepared by polymerization method using double metal ions of Fe^(3+)and Mn^(2+)as cross-linking agents.Preparation conditions such as metal ions concentration,mass fraction of SA,polymerization temperature and dual-metal ions as crosslinking agent were optimized.Moreover,the effects of operating conditions such as initial concentration of CIP,pH value and catalyst dosage on CIP removal were studied.The kinetic equation showed that the effect of the initial concentration of CIP on the degradation rate was in line with second-order kinetics,and the effects of catalyst dosage and pH value on the degradation rate of CIP were in line with first-order kinetics.The SA gel microspheres catalysts prepared by dual-metal ions exhibited a high CIP removal and showed a good reusability after six recycles.The SA gel microspheres catalysts with an easy recovery performance provided an economical and efficient method for the removal of antibiotics in the future.展开更多
Nitrate from the application of nitrogen-based fertilizers in intensive agriculture is a notorious waste product, though it lacks cost-effective solutions for its removal from potential drinking water resources. Catal...Nitrate from the application of nitrogen-based fertilizers in intensive agriculture is a notorious waste product, though it lacks cost-effective solutions for its removal from potential drinking water resources. Catalytic reduction appears to be a promising technique for converting nitrates to benign nitrogen gas. Mesoporous silica SBA-15 is a frequently used catalyst support that has large surface areas and highly ordered nanopores. In this work, mesoporous silica SBA-15 bimetallic catalysts for nitrate reduction were investigated. The catalyst was optimized for the selection of promoter metal (Sn and Cu), noble metal (Pd and Pt) and loading ratios of these metals at different temperatures and reduction conditions. The catalysts prepared were characterized by FT-IR, N2 physisorption, XRD, SEM, and ICP. All catalysts showed the presence of cylindrical mesoporous channels and uniform pore structures that remained even after metals loading. In the presence of a CO<sub>2</sub> buffer, the catalysts 4Pd-1Cu/SBA-15 and 1Pt-1Cu/SBA-15 reduced at 100?C under H2 and 1Pd-1Cu/SBA-15 reduced at 200°C under H2 demonstrated very high nitrate conversion. Furthermore, the forementioned Pd catalysts had higher N2 selectivity (88% - 87%) compared to Pt catalyst (80%). Nitrate conversion by the 4Pd-1Cu/SBA-15 catalyst was significantly decreased to 81% in the absence of CO<sub>2</sub>.展开更多
Heterogeneous catalysts are the most important catalysts in industrial reactions. Nanocatalysts, with size ranging from hundreds of nanometers to the atomic scale, possess activities that are closely connected to thei...Heterogeneous catalysts are the most important catalysts in industrial reactions. Nanocatalysts, with size ranging from hundreds of nanometers to the atomic scale, possess activities that are closely connected to their structural characteristics such as particle size, surface morphology, and three-dimensional topography. Recently, the development of advanced analytical transmission electron microscopy(TEM) techniques, especially quantitative high-angle annular darkfield(HAADF) imaging and high-energy resolution spectroscopy analysis in scanning transmission electron microscopy(STEM) at the atomic scale, strengthens the power of(S)TEM in analyzing the structural/chemical information of heterogeneous catalysts. Three-dimensional reconstruction from two-dimensional projected images and the real-time recording of structural evolution during catalytic reactions using in-situ(S)TEM methods further broaden the scope of(S)TEM observation. The atomic-scale structural information obtained from high-resolution(S)TEM has proven to be of significance for better understanding and designing of new catalysts with enhanced performance.展开更多
Energy obtained from a variety of non-renewable sources is considered unsustainable. Various fossil fuels, such as petroleum, coal, and natural gas, are among these sources. The combustion of fossil fuels resulted in ...Energy obtained from a variety of non-renewable sources is considered unsustainable. Various fossil fuels, such as petroleum, coal, and natural gas, are among these sources. The combustion of fossil fuels resulted in the generation of greenhouse gases, which increased the amount of carbon dioxide in the atmosphere. Global warming and ozone layer degradation are the negative consequences. In a country like India, where consumable oils are still imported, it is sense to look at the possibility of using such unpalatable oils in CI engines that aren’t often utilized as cooking oil. Palm oil is a vegetable oil obtained from the monocarp of the oil palm’s crop. The main goal is to provide a low-cost, high-performance alternative to diesel. The possibility of palm oil as a realistic, modest, and effective hotspot for the generation of biodiesel is investigated in this research. The article is focused on the comparison of palm oil and diesel in terms of characteristics.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
Pure metal-doped(Cu,Zn)Fe2O4 was synthesized from Zn-containing electric arc furnace dust(EAFD)by solid-state reaction using copper salt as additive.The effects of pretreated EAFD-to-Cu2(OH)2CO3·6H2O mass ratio,c...Pure metal-doped(Cu,Zn)Fe2O4 was synthesized from Zn-containing electric arc furnace dust(EAFD)by solid-state reaction using copper salt as additive.The effects of pretreated EAFD-to-Cu2(OH)2CO3·6H2O mass ratio,calcination time,and calcination temperature on the structure and catalytic ability were systematically studied.Under the optimum conditions,the decolorization efficiency and total organic carbon(TOC)removal efficiency of the as-prepared ferrite for treating a Rhodamine B solution were approximately 90.0%and 45.0%,respectively,and the decolorization efficiency remained 83.0%after five recycles,suggesting that the as-prepared(Cu,Zn)Fe2O4 was an efficient heterogeneous Fenton-like catalyst with high stability.The high catalytic activity mainly depended on the synergistic effect of iron and copper ions occupying octahedral positions.More importantly,the toxicity characteristic leaching procedure(TCLP)analysis illustrated that the toxic Zncontaining EAFD was transformed into harmless(Cu,Zn)Fe2O4 and that the concentrations of toxic ions in the degraded solution were all lower than the national emission standard(GB/31574-2015),further confirming that the as obtained sample is an environment-friendly heterogeneous Fenton-like catalyst.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.
The use of non-equilibrium plasmas for the synthesis of heterogeneous catalysts is a field that has not been explored intensively. The main reasons for the recent increase of research activity in this field are relate...The use of non-equilibrium plasmas for the synthesis of heterogeneous catalysts is a field that has not been explored intensively. The main reasons for the recent increase of research activity in this field are related to the advantages that go with the technique of plasma enhanced chemical vapor deposition (PECVD). The most principal of these advantages are the possibility to avoid the use of environmentally harmful solvents and the one-step nature of the procedure, making it very time and labor efficient. Non-equilibrium plasma technology, more in particular dielectric barrier discharge (DBD) technology, has been applied in this work for the synthesis of hybrid tin-silicate materials to be used as a heterogeneous catalyst in the isomerization of glucose into fructose. Atomizers, innovative devices which make it possible to inject nanosized precursor liquids into the plasma zone, are used instead of applying vapor phase techniques, where the amount of precursor is limited by the vapor pressure of the liquid. A design of experiments approach has been employed to investigate the effect of the plasma parameters, namely gas flow, frequency and power density, on the catalytic properties of the catalysts within a well-defined parameter field. It has been found that indeed these parameters, together with the molar ratio of Si/Sn, have an important influence on the activity, selectivity, and thus yield of the produced chemicals.展开更多
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.
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.
基金This study was supported by the National Natural Science Foundations of China(Nos.51902027,61874014,61874013,51788104,61974011 and 61976025)the Basic Science Center Program of the National Natural Science Foundation of China(No.51788104)+2 种基金National Basic Research of China(Nos.2016YFE0102200 and 2018YFB0104404)Beijing Natural Science Foundation(No.JQ19005)Fund of State Key Laboratory of Information Photonics and Optical Communications(Beijing University of Posts and Telecommunications,China).
文摘Being a typical state of the art heterogeneous catalyst,supported noble metal catalyst often demonstrates enhanced catalytic properties.However,a facile synthetic method for realizing large-scale and low-cost supported noble metal catalyst is strictly indispensable.To this end,by making use of the strong metal-support interaction(SMSI)and mechanochemical reaction,we introduce an efficient synthetic route to obtain ultrafine Pt and Ir nanoclusters immobilized on diverse substrates by wet chemical milling.We further demonstrate the scaling-up effect of our approach by large-scale ball-milling production of Pt nanoclusters immobilized on TiO_(2)substrate.The synthesized Pt/Ir@Co_(3)O_(4)catalysts exhibit superior oxygen evolution reaction(OER)performance with only 230 and 290 mV overpotential to achieve current density of 10 and 100 mA·cm^(-2),beating the catalytic performance of Co_(3)O_(4)supported Pt or Ir clusters and commercial Ir/C.It is envisioned that the present work strategically directs facile ways for fabricating supported noble metal heterogeneous catalysts.
基金National Natural Science Foundation of China(NSFC-21871046)Fundamental Research Funds for the Central Universities and Graduate Student Innovation Fund of Donghua University.
文摘Main observation and conclusion We describe a practical and general protocol for immobilization of heterogeneous catalysts to mechanically robust porous ultra-high molecular weight polyethylene tablets using inter-facial Lifshitz-van der Waals Interactions.Diverse types of powderous catalysts,including Cu,Pd/C,Pd/Al2O3,Pt/C,and Rh/C have been immobilized successfully.The immobilized catalysts are mechanistically robust towards stirring in solutions,and they worked well in diverse synthetic reactions.The immobilized catalyst tablets are easy to handle and reused.Moreover,the metal leaching of immobilized catalysts was reduced significantly.
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.
基金supported by the National Natural Science Foundation of China(22125802 and 22108012)Natural Science Foundation of Beijing Municipality(2222017)Fundamental Research Funds for the Central Universities(BUCTRC-202109)。
文摘The discharge of the antibiotic wastewater has increased dramatically in our country with the development of medical science and wide application of antibiotic,resulting in serious harm to human body and ecological environment.In this work,ciprofloxacin(CIP)was selected as one of typical antibiotics and heterogeneous Fenton-like catalysts were prepared for the treatment of ciprofloxacin wastewater.The sodium alginate(SA)gel microspheres catalysts were prepared by polymerization method using double metal ions of Fe^(3+)and Mn^(2+)as cross-linking agents.Preparation conditions such as metal ions concentration,mass fraction of SA,polymerization temperature and dual-metal ions as crosslinking agent were optimized.Moreover,the effects of operating conditions such as initial concentration of CIP,pH value and catalyst dosage on CIP removal were studied.The kinetic equation showed that the effect of the initial concentration of CIP on the degradation rate was in line with second-order kinetics,and the effects of catalyst dosage and pH value on the degradation rate of CIP were in line with first-order kinetics.The SA gel microspheres catalysts prepared by dual-metal ions exhibited a high CIP removal and showed a good reusability after six recycles.The SA gel microspheres catalysts with an easy recovery performance provided an economical and efficient method for the removal of antibiotics in the future.
文摘Nitrate from the application of nitrogen-based fertilizers in intensive agriculture is a notorious waste product, though it lacks cost-effective solutions for its removal from potential drinking water resources. Catalytic reduction appears to be a promising technique for converting nitrates to benign nitrogen gas. Mesoporous silica SBA-15 is a frequently used catalyst support that has large surface areas and highly ordered nanopores. In this work, mesoporous silica SBA-15 bimetallic catalysts for nitrate reduction were investigated. The catalyst was optimized for the selection of promoter metal (Sn and Cu), noble metal (Pd and Pt) and loading ratios of these metals at different temperatures and reduction conditions. The catalysts prepared were characterized by FT-IR, N2 physisorption, XRD, SEM, and ICP. All catalysts showed the presence of cylindrical mesoporous channels and uniform pore structures that remained even after metals loading. In the presence of a CO<sub>2</sub> buffer, the catalysts 4Pd-1Cu/SBA-15 and 1Pt-1Cu/SBA-15 reduced at 100?C under H2 and 1Pd-1Cu/SBA-15 reduced at 200°C under H2 demonstrated very high nitrate conversion. Furthermore, the forementioned Pd catalysts had higher N2 selectivity (88% - 87%) compared to Pt catalyst (80%). Nitrate conversion by the 4Pd-1Cu/SBA-15 catalyst was significantly decreased to 81% in the absence of CO<sub>2</sub>.
基金Project supported by the Natural Science Foundation of China(Grant No.51622211)the Pioneer Hundred Talents Program of Chinese Academy of Sciences
文摘Heterogeneous catalysts are the most important catalysts in industrial reactions. Nanocatalysts, with size ranging from hundreds of nanometers to the atomic scale, possess activities that are closely connected to their structural characteristics such as particle size, surface morphology, and three-dimensional topography. Recently, the development of advanced analytical transmission electron microscopy(TEM) techniques, especially quantitative high-angle annular darkfield(HAADF) imaging and high-energy resolution spectroscopy analysis in scanning transmission electron microscopy(STEM) at the atomic scale, strengthens the power of(S)TEM in analyzing the structural/chemical information of heterogeneous catalysts. Three-dimensional reconstruction from two-dimensional projected images and the real-time recording of structural evolution during catalytic reactions using in-situ(S)TEM methods further broaden the scope of(S)TEM observation. The atomic-scale structural information obtained from high-resolution(S)TEM has proven to be of significance for better understanding and designing of new catalysts with enhanced performance.
文摘Energy obtained from a variety of non-renewable sources is considered unsustainable. Various fossil fuels, such as petroleum, coal, and natural gas, are among these sources. The combustion of fossil fuels resulted in the generation of greenhouse gases, which increased the amount of carbon dioxide in the atmosphere. Global warming and ozone layer degradation are the negative consequences. In a country like India, where consumable oils are still imported, it is sense to look at the possibility of using such unpalatable oils in CI engines that aren’t often utilized as cooking oil. Palm oil is a vegetable oil obtained from the monocarp of the oil palm’s crop. The main goal is to provide a low-cost, high-performance alternative to diesel. The possibility of palm oil as a realistic, modest, and effective hotspot for the generation of biodiesel is investigated in this research. The article is focused on the comparison of palm oil and diesel in terms of characteristics.
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financially supported by the National Natural Science Foundation of China(No.U1810205)the National Basic Research Program of China(No.2014CB 643401)Shanxi Collaborative Innovation Center of High Value-added Utilization of Coal-related Wastes。
文摘Pure metal-doped(Cu,Zn)Fe2O4 was synthesized from Zn-containing electric arc furnace dust(EAFD)by solid-state reaction using copper salt as additive.The effects of pretreated EAFD-to-Cu2(OH)2CO3·6H2O mass ratio,calcination time,and calcination temperature on the structure and catalytic ability were systematically studied.Under the optimum conditions,the decolorization efficiency and total organic carbon(TOC)removal efficiency of the as-prepared ferrite for treating a Rhodamine B solution were approximately 90.0%and 45.0%,respectively,and the decolorization efficiency remained 83.0%after five recycles,suggesting that the as-prepared(Cu,Zn)Fe2O4 was an efficient heterogeneous Fenton-like catalyst with high stability.The high catalytic activity mainly depended on the synergistic effect of iron and copper ions occupying octahedral positions.More importantly,the toxicity characteristic leaching procedure(TCLP)analysis illustrated that the toxic Zncontaining EAFD was transformed into harmless(Cu,Zn)Fe2O4 and that the concentrations of toxic ions in the degraded solution were all lower than the national emission standard(GB/31574-2015),further confirming that the as obtained sample is an environment-friendly heterogeneous Fenton-like catalyst.
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.
基金the PhD scholarship,awarded by VITO,and the funding granted by SBO-IWT,IAP(Belspo)the Methusalem long-term financing of the Flemish government
文摘The use of non-equilibrium plasmas for the synthesis of heterogeneous catalysts is a field that has not been explored intensively. The main reasons for the recent increase of research activity in this field are related to the advantages that go with the technique of plasma enhanced chemical vapor deposition (PECVD). The most principal of these advantages are the possibility to avoid the use of environmentally harmful solvents and the one-step nature of the procedure, making it very time and labor efficient. Non-equilibrium plasma technology, more in particular dielectric barrier discharge (DBD) technology, has been applied in this work for the synthesis of hybrid tin-silicate materials to be used as a heterogeneous catalyst in the isomerization of glucose into fructose. Atomizers, innovative devices which make it possible to inject nanosized precursor liquids into the plasma zone, are used instead of applying vapor phase techniques, where the amount of precursor is limited by the vapor pressure of the liquid. A design of experiments approach has been employed to investigate the effect of the plasma parameters, namely gas flow, frequency and power density, on the catalytic properties of the catalysts within a well-defined parameter field. It has been found that indeed these parameters, together with the molar ratio of Si/Sn, have an important influence on the activity, selectivity, and thus yield of the produced chemicals.