The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation...The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation of CO_(2)to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce CO_(2)emissions.Although significant volumes of methanol are currently produced from CO_(2),developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process costs.An in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C coupling.Identifying these factors guides us toward developing more effective catalysts for ethanol synthesis.In this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or ethanol.The catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and presented.The following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO_(2)into ethanol.Lastly,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts.展开更多
Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active...Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active centers influencing the rate of both methanol and CO formation.The particle size and the interaction between Cu and the support materials are influenced by the coprecipitation conditions,let alone that the mechanistic divergence remains unclear.In this work,a series of Cu/ZnO/ZrO_(2) catalysts were prepared via co-precipitation at different pH value and systematically characterized.The structure has been correlated with kinetic results to establish the structure-performance relationship.Kinetic analysis demonstrates that methanol synthesis follows a single-site Langmuir-Hinshelwood(L-H)mechanism,i.e.,Cu serves as the active site where CO_(2) and H_(2) competitively adsorb and react to form methanol.In contrast,CO formation proceeds via a dual-site L-H mechanism,where CO_(2) adsorbs onto ZnO and H_(2) onto Cu,with the reaction occurring at the Cu/ZnO interface.Therefore,for the direct formation of methanol,solely reducing the particle size of Cu would not be beneficial.展开更多
The direct oxidation of methane to methanol(DOMM) has been recognized as a significant technology for efficiently utilizing low-concentration coalbed methane(LCMM) and supplying liquid fuel.Herein,the noble metals(Pt,...The direct oxidation of methane to methanol(DOMM) has been recognized as a significant technology for efficiently utilizing low-concentration coalbed methane(LCMM) and supplying liquid fuel.Herein,the noble metals(Pt,Pd and Ru) modified Cu/alkalized sepiolite(CuX/SEPA) catalysts were prepared and used for the DOMM in a gas-phase system at low temperatures.The CuRu/SEPA exhibited the highest methanol production of 53 μmol·g^(-1)·h^(-1) and methanol selectivity of 90% under the optimal reaction conditions.Various characterizations demonstrated that the addition of Ru promoted the formation of Cu^(2+)and the contraction of Cu—Si/Al bonds to reduce the distance between framework Al atoms of SEPA to further generate more Al pairs,which facilitated the formation of reactive dicopper species([Cu_(2)O]^(2+)or [Cu_(2)O_(2)]^(2+)).Investigation of the reaction mechanism revealed that [Cu_(2)O]^(2+) or [Cu_(2)O_(2)]^(2+) species could adsorb and activate methane to form CH_(3)O^(*) species and ultimately generated methanol with the assistance of water.展开更多
Iron-Vanadium(FeV)catalyst showed a unique catalytic activity for the selective oxidation of methanol to formaldehyde;however,due to its complex compositions,the identification of catalytic active sites still remains ...Iron-Vanadium(FeV)catalyst showed a unique catalytic activity for the selective oxidation of methanol to formaldehyde;however,due to its complex compositions,the identification of catalytic active sites still remains challenging,inhibiting the rational design of excellent FeV-based catalysts.Here,in this work,a series of FeV catalysts with various compositions,including FeVO_(4),isolated VO_(x),low-polymerized V_(n)O_(x),and crystalline V_(2)O_(5) were prepared by controlling the preparation conditions,and were applied to methanol oxidation to formaldehyde reaction.A FeV_(1.1) catalyst,which consisted of FeVO_(4) and low-polymerized V_(n)O_(x) species showed an excellent catalytic performance with a methanol conversion of 92.3%and a formaldehyde selectivity of 90.6%,which was comparable to that of conventional iron-molybdate catalyst.The results of CH_(3)OH-IR,O_(2) pulse and control experiments revealed a crucial synergistic effect between FeVO_(4) and low-polymerized V_(n)O_(x).It enhanced the oxygen supply capacity and suitable binding and adsorption strengths for formaldehyde intermediates,contributing to the high catalytic activity and formaldehyde selectivity.This study not only advances the understanding of FeV structure but also offers valuable guidelines for selective methanol oxidation to formaldehyde.展开更多
This work investigates the potential of low-pressure,medium-speed dual-fuel engines for cleaner maritime transportation.The thermodynamic performance of these engines is explored using three alternative fuels:liquefie...This work investigates the potential of low-pressure,medium-speed dual-fuel engines for cleaner maritime transportation.The thermodynamic performance of these engines is explored using three alternative fuels:liquefied natural gas(LNG),methanol,and ammonia.A parametric analysis examines the effect of adjustments to key engine parameters(compression ratio,boost pressure,and air-fuel ratio)on performance.Results show an initial improvement in performance with an increase in compression ratio,which reaches a peak and then declines.Similarly,increases in boost pressure and air-fuel ratio lead to linear performance gains.However,insufficient cooling reduces the amount of fuel burned,which hinders performance.Exergy analysis reveals significant exergy destruction within the engine,which ranges from 69.96%(methanol)to 78.48%(LNG).Notably,the combustion process is the leading cause of exergy loss.Among the fuels tested,methanol exhibits the lowest combustion-related exergy destruction(56.41%),followed by ammonia(62.12%)and LNG(73.77%).These findings suggest that methanol is a promising near-term alternative to LNG for marine fuel applications.展开更多
CuZn-based catalyst is an attractive catalyst for methanol synthesis from CO_(2)hydrogenation,but it early deactivates and its methanol yield still needs to improve.In this study,Y_(2)O_(3)was introduced to Cu/ZnO usi...CuZn-based catalyst is an attractive catalyst for methanol synthesis from CO_(2)hydrogenation,but it early deactivates and its methanol yield still needs to improve.In this study,Y_(2)O_(3)was introduced to Cu/ZnO using a one-pot hydrothermal method,and exhibits a synergistic effect of ZnO and Y_(2)O_(3)on enhancing methanol yield and the stability.We found that the interaction between Y_(2)O_(3)and ZnO results in abundant oxygen vacancies formation,thereby enhancing CO_(2)adsorption and activation.Kinetic analysis and in situ DRIFTS suggest that RWGS forming CO and methanol formation compete for a mutual intermediate HCOO^(*),and the introduction of Y_(2)O_(3)to Cu/ZnO raises the energy barrier for the CO formation but lowers that for methanol formation,thus enhancing the methanol yield on Cu/ZnO/Y_(2)O_(3).展开更多
Designing advanced electrocatalysts with high methanol tolerance in the oxygen reduction reaction process is crucial for the sustainable implementation of direct methanol fuel cells.Herein,we present a Pt/C catalyst m...Designing advanced electrocatalysts with high methanol tolerance in the oxygen reduction reaction process is crucial for the sustainable implementation of direct methanol fuel cells.Herein,we present a Pt/C catalyst modified with black phosphorus(BP)nanodots(BPNDs-Pt/C)by using a facile ultrasonic mixing method.Experimental and computational investigations reveal that the electron transfer from BP to Pt leads to weak adsorption of hydroxyl groups on the Pt surface.As a result,the BPNDs-Pt/C catalyst exhibits efficient activity and anti-methanol ability for cathodic oxygen reduction electrocatalysis in an acidic medium.Additionally,it demonstrates high activity for oxygen reduction reaction(ORR)in an alternative alkaline system with cation exchange membrane and eliminable methanol penetration.This work highlights the feasibility of using non-metallic elements to regulate the electronic structure and surface properties of Pt-based nanomaterials.Furthermore,the designed BPNDs-Pt/C electrocatalyst,with controllable ORR performance,can be applied across various scenarios based on demand.展开更多
ITR zeolite could be potentially used as catalysts in methanol to propylene(MTP),where their performance is strongly related to its Al distribution.However,the control of Al distribution in ITR zeolite poses a signifi...ITR zeolite could be potentially used as catalysts in methanol to propylene(MTP),where their performance is strongly related to its Al distribution.However,the control of Al distribution in ITR zeolite poses a significant synthetic challenge.Herein,we demonstrate the possibility to control the Al distribution in ITR zeolites using zeolite A as an aluminum source(A-ITR).The A-ITR exhibited similar crystallinity,nanosheet morphology,textual parameters,and acidic concentration with those of conventional ITR made zeolites using aluminum isopropoxide as an aluminum source(C-ITR).Characterizations of the zeolite product with^(27)Al MQ.MAS NMR spectra,^(27)Al MAS NMR spectra,and 1-hexene cracking reveal that the A-ITR zeolites have more Al species distributed in T6 and T8 sites located in relatively smaller micropores of the framework than C-ITR.As a result,the A-ITR gave enhanced catalyst lifetime and propylene selectivity due to the suppression of the aromatic cycle in the MTP reaction,compared with the C-ITR.This work provides an alternative approach to prepare efficient ITR zeolites for MTP reaction.展开更多
Based upon the thiophene-2,5-dicarboxylic acid(H_(2)Tdc),a novel[Sc_(3)(μ_(2)-OH)_(3)(CO_(2))_(4)O_(6)]n inorganic chain-based Sc-MOF with decorated nitrate ions,{[Sc_(3)(OH)_(2)(Tdc)_(3)(NO_(3))]⋅H_(2)O}_(∞)(AEU-1;...Based upon the thiophene-2,5-dicarboxylic acid(H_(2)Tdc),a novel[Sc_(3)(μ_(2)-OH)_(3)(CO_(2))_(4)O_(6)]n inorganic chain-based Sc-MOF with decorated nitrate ions,{[Sc_(3)(OH)_(2)(Tdc)_(3)(NO_(3))]⋅H_(2)O}_(∞)(AEU-1;AEU for Army Engineering University of PLA),was synthesized,which shows good water and chemical stabilities.Significantly,due to channel constriction accompanied by the polar window caused by introducing nitrate ions,AEU-1 exhibits high C_(2)H_(6)/C_(2)H_(4)adsorption selectivity comparable to many famous C_(2)H_(6)-selective MOFs,making it a promising candidate for the purification of methanol-to-olefin(MTO)products.Furthermore,theoretical investigations reveal that the introduced nitrate ions in AEU-1 as the main adsorption sites could provide strong interactions between the framework and C2H6/C3H6 in the full-contacting mode,leading to an increase in the adsorption enthalpies(Qst)of C_(2)H_(6)and C_(3)H_(6),and thus further improving the C_(2)H_(6)/C_(2)H_(4)and C_(3)H_(6)/C_(2)H_(4)adsorption selectivity.Our work could open up a new avenue for constructing MOFs with inorganic polar moieties as adsorption sites for one-step C_(2)H_(4)purification and C3H6 recovery from MTO mixtures with high selectivity.展开更多
One-step direct production of methanol from methane and water(PMMW)under mild conditions is challenging in heterogeneous catalysis owing to the absence of highly effective catalysts.Herein,we designed a series of“Sin...One-step direct production of methanol from methane and water(PMMW)under mild conditions is challenging in heterogeneous catalysis owing to the absence of highly effective catalysts.Herein,we designed a series of“Single-Atom”-“Frustrated Lewis Pair”(SA-FLP)dual active sites for the direct PMMW via density functional theory(DFT)calculations combined with a machine learning(ML)approach.The results indicate that the nine designed SA-FLP catalysts are capable of efficiently activate CH4 and H_(2)O and facilitate the coupling of OH^(*)and CH_(3)^(*)into methanol.The DFT-based microkinetic simulation(MKM)results indicate that CH_(3)OH production on Co1-FLP and Pt1-FLP catalysts can reach the turnover frequencies(TOFs)of 1.01×10^(−3)s^(-1)and 8.80×10^(−4)s^(-1),respectively,which exceed the experimentally reported values by three orders of magnitude.ML results unveil that the gradient boosted regression model with 13 simple features could give satisfactory predictions for the TOFs of CH_(3)OH production with RMSE and R^(2)of 0.009 s^(-1)and 1.00,respectively.The ML-predicted MKM results indicate that four catalysts including V_(1-),Fe_(1-),Ti_(1-),and Mn_(1)-FLP exhibit higher TOFs of CH_(3)OH production than the value that the most relevant experiments reported,indicating that the four catalysts are also promising catalysts for the PMMW.This study not only develops a simple and efficient approach for design and screening SA-FLP catalysts but also provides mechanistic insights into the direct PMMW.展开更多
The increasingly serious climate issue compels urgent greenhouse gas mitigation strategies.As a budget,plentiful,renewable feedstock and major contributor to global warming,the large-scale catalytic transformation of ...The increasingly serious climate issue compels urgent greenhouse gas mitigation strategies.As a budget,plentiful,renewable feedstock and major contributor to global warming,the large-scale catalytic transformation of CO_(2)has attracted widespread attention from society due to its potential as a solution to the environment and energy crises.At present,catalytic hydrogenation of carbon dioxide to organic chemicals is the primary approach in its industrial applications.In recent decades,various materials containing Cu-,precious metal-,In-,Zn-,and Ga-based catalysts have been designed for CO_(2)hydrogenation to methanol.Likewise,great advances have been made in CO_(2)-to-chemicals,such as olefins,aromatics,and gasoline by combining CO_(2)-to-CH3OH with methanol transformation or tandem reaction of reverse water-gas shift and Fischer-Tropsch(FT)synthesis.This review exhibits the recent advances in the hydrogenation of CO_(2)-to-CH3OH including the catalyst system,CO_(2)activation,nature of active sites,intermediate species(formate or carboxyl),structure-activity relationship,and reaction mechanism.Finally,challenges and outlooks in CO_(2)hydrogenation to methanol are summarized.展开更多
The sluggish reaction kinetics of the oxygen evolution reaction(OER)and methanol oxidation reaction(MOR)remain obstacles to the commercial promotion of water splitting and direct methanol fuel cells.Considering the vi...The sluggish reaction kinetics of the oxygen evolution reaction(OER)and methanol oxidation reaction(MOR)remain obstacles to the commercial promotion of water splitting and direct methanol fuel cells.Considering the vital role of noble metals in electrocatalytic activity,this work focuses on the rational synthesis of Ni-noble metal composite nanocatalysts for overcoming the drawbacks of high cost and susceptible oxidized surfaces of noble metals.The inherent catalytic activity is improved by the altered electronic structure and effective active sites of the catalyst induced by the size effect of noble metal clusters.In particular,a series of Ni-noble metal nanocomposites are successfully synthesized by partially introducing noble metal into Ni with porous interfacial defects derived from Ni-Al layered double hydroxide(LDH).The Ni_(10)Pd_(1)nanocomposite exhibits high OER catalytic activity with an overpotential of 0.279 V at 10 m A/cm^(2),surpassing Ni_(10)Ag_(1)and Ni_(10)Au_(1)counterparts.Furthermore,the average diameter of Pd clusters gradually increases from 5.57 nm to 44.44 nm with the increased proportion of doped Pd,leading to the passivation of catalytic activity due to the exacerbated surface oxidation of Pd in the form of Pd^(2+).After optimization,Ni_(10)Pd_(1)delivers significantly enhanced OER and MOR electroactivities and long-term stability compared to that of Ni_(2)Pd_(1),Ni_(1)Pd_(1)and Ni_(1)Pd_(2),which is conducive to the effective utilization of Pd and alleviation of surface oxidation.展开更多
Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride he...Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures(denoted PtPdAu/BiTe)were synthesized using a visible-light-assisted strategy.The coupling alloy and interfacial effects of PtPdAu/BiTe significantly improved the performance and stability of both the ethanol oxidation reaction(EOR)and methanol oxidation reaction(MOR).Introducing a small amount of Au effectively enhanced the CO tolerance of PtPdAu/BiTe compared to dendritic platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures.PtPdAu/BiTe exhibited mass activities of 31.5 and 13.3 A·mg_(Pt)^(-1)in EOR and MOR,respectively,which were 34.4 and 13.2 times higher than those of commercial Pt black,revealing efficient Pt atom utilization.In-situ Fourier transform infrared spectroscopy demonstrated complete 12e^(-)and 6e^(-)oxidation of ethanol and methanol on PtPdAu/BiTe.The PtPdAu/BiTe/C achieved mass peak power densities of 131 and 156 mW·mg_(Pt)^(-1),which were 2.4 and 2.2 times higher than those of Pt/C in practical direct ethanol fuel cell(DEFC)and direct methanol fuel cell(DMFC),respectively,highlighting their potential application in DEFC and DMFC.This study introduces an effective strategy for designing efficient and highly CO tolerant anodic electrocatalysts for practical DEFC and DMFC applications.展开更多
Against the backdrop of global energy and environmental crises,the technology of CO_(2)hydrogenation to produce methanol is garnering widespread attention as an innovative carbon capture and utilization solution.Bimet...Against the backdrop of global energy and environmental crises,the technology of CO_(2)hydrogenation to produce methanol is garnering widespread attention as an innovative carbon capture and utilization solution.Bimetallic oxide catalysts have emerged as the most promising research subject in the field due to their exceptional catalytic performance and stability.The performance of bimetallic oxide catalysts is influenced by multiple factors,including the selection of carrier materials,the addition of promoters,and the synthesis process.Different types of bimetallic oxide catalysts exhibit significant differences in microstructure,surface active sites,and electronic structure,which directly determine the yield and selectivity of methanol.Although bimetallic oxide catalysts offer significant advantages over traditional copper-based catalysts,they still encounter challenges related to activity and cost.In order to enhance catalyst performance,future investigations must delve into microstructure control,surface modification,and reaction kinetics.展开更多
基金the Canadian NRCan OERD Energy Innovation Programthe Natural Sciences and Engineering Research Council of Canada,and the Carbon Solution Program for their financial support.
文摘The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation of CO_(2)to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce CO_(2)emissions.Although significant volumes of methanol are currently produced from CO_(2),developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process costs.An in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C coupling.Identifying these factors guides us toward developing more effective catalysts for ethanol synthesis.In this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or ethanol.The catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and presented.The following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO_(2)into ethanol.Lastly,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts.
基金supported by Research Grant from China Petroleum and Chemical Corp。
文摘Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active centers influencing the rate of both methanol and CO formation.The particle size and the interaction between Cu and the support materials are influenced by the coprecipitation conditions,let alone that the mechanistic divergence remains unclear.In this work,a series of Cu/ZnO/ZrO_(2) catalysts were prepared via co-precipitation at different pH value and systematically characterized.The structure has been correlated with kinetic results to establish the structure-performance relationship.Kinetic analysis demonstrates that methanol synthesis follows a single-site Langmuir-Hinshelwood(L-H)mechanism,i.e.,Cu serves as the active site where CO_(2) and H_(2) competitively adsorb and react to form methanol.In contrast,CO formation proceeds via a dual-site L-H mechanism,where CO_(2) adsorbs onto ZnO and H_(2) onto Cu,with the reaction occurring at the Cu/ZnO interface.Therefore,for the direct formation of methanol,solely reducing the particle size of Cu would not be beneficial.
基金financial assistance from the Anhui Provincial Major Science and Technology Project(202003a05020022)the Institute of Energy,Hefei Comprehensive National Science Center(21KZS219)。
文摘The direct oxidation of methane to methanol(DOMM) has been recognized as a significant technology for efficiently utilizing low-concentration coalbed methane(LCMM) and supplying liquid fuel.Herein,the noble metals(Pt,Pd and Ru) modified Cu/alkalized sepiolite(CuX/SEPA) catalysts were prepared and used for the DOMM in a gas-phase system at low temperatures.The CuRu/SEPA exhibited the highest methanol production of 53 μmol·g^(-1)·h^(-1) and methanol selectivity of 90% under the optimal reaction conditions.Various characterizations demonstrated that the addition of Ru promoted the formation of Cu^(2+)and the contraction of Cu—Si/Al bonds to reduce the distance between framework Al atoms of SEPA to further generate more Al pairs,which facilitated the formation of reactive dicopper species([Cu_(2)O]^(2+)or [Cu_(2)O_(2)]^(2+)).Investigation of the reaction mechanism revealed that [Cu_(2)O]^(2+) or [Cu_(2)O_(2)]^(2+) species could adsorb and activate methane to form CH_(3)O^(*) species and ultimately generated methanol with the assistance of water.
文摘Iron-Vanadium(FeV)catalyst showed a unique catalytic activity for the selective oxidation of methanol to formaldehyde;however,due to its complex compositions,the identification of catalytic active sites still remains challenging,inhibiting the rational design of excellent FeV-based catalysts.Here,in this work,a series of FeV catalysts with various compositions,including FeVO_(4),isolated VO_(x),low-polymerized V_(n)O_(x),and crystalline V_(2)O_(5) were prepared by controlling the preparation conditions,and were applied to methanol oxidation to formaldehyde reaction.A FeV_(1.1) catalyst,which consisted of FeVO_(4) and low-polymerized V_(n)O_(x) species showed an excellent catalytic performance with a methanol conversion of 92.3%and a formaldehyde selectivity of 90.6%,which was comparable to that of conventional iron-molybdate catalyst.The results of CH_(3)OH-IR,O_(2) pulse and control experiments revealed a crucial synergistic effect between FeVO_(4) and low-polymerized V_(n)O_(x).It enhanced the oxygen supply capacity and suitable binding and adsorption strengths for formaldehyde intermediates,contributing to the high catalytic activity and formaldehyde selectivity.This study not only advances the understanding of FeV structure but also offers valuable guidelines for selective methanol oxidation to formaldehyde.
文摘This work investigates the potential of low-pressure,medium-speed dual-fuel engines for cleaner maritime transportation.The thermodynamic performance of these engines is explored using three alternative fuels:liquefied natural gas(LNG),methanol,and ammonia.A parametric analysis examines the effect of adjustments to key engine parameters(compression ratio,boost pressure,and air-fuel ratio)on performance.Results show an initial improvement in performance with an increase in compression ratio,which reaches a peak and then declines.Similarly,increases in boost pressure and air-fuel ratio lead to linear performance gains.However,insufficient cooling reduces the amount of fuel burned,which hinders performance.Exergy analysis reveals significant exergy destruction within the engine,which ranges from 69.96%(methanol)to 78.48%(LNG).Notably,the combustion process is the leading cause of exergy loss.Among the fuels tested,methanol exhibits the lowest combustion-related exergy destruction(56.41%),followed by ammonia(62.12%)and LNG(73.77%).These findings suggest that methanol is a promising near-term alternative to LNG for marine fuel applications.
文摘CuZn-based catalyst is an attractive catalyst for methanol synthesis from CO_(2)hydrogenation,but it early deactivates and its methanol yield still needs to improve.In this study,Y_(2)O_(3)was introduced to Cu/ZnO using a one-pot hydrothermal method,and exhibits a synergistic effect of ZnO and Y_(2)O_(3)on enhancing methanol yield and the stability.We found that the interaction between Y_(2)O_(3)and ZnO results in abundant oxygen vacancies formation,thereby enhancing CO_(2)adsorption and activation.Kinetic analysis and in situ DRIFTS suggest that RWGS forming CO and methanol formation compete for a mutual intermediate HCOO^(*),and the introduction of Y_(2)O_(3)to Cu/ZnO raises the energy barrier for the CO formation but lowers that for methanol formation,thus enhancing the methanol yield on Cu/ZnO/Y_(2)O_(3).
基金supported by the National Natural Science Foundation of China(No.22208322)the Natural Science Foundation of Henan(No.242300421230)+1 种基金the Key Research Projects of Higher Education Institutions of Henan Province(No.24A530009)the Special Fund for Young Teachers from Zhengzhou University(No.JC23257011).
文摘Designing advanced electrocatalysts with high methanol tolerance in the oxygen reduction reaction process is crucial for the sustainable implementation of direct methanol fuel cells.Herein,we present a Pt/C catalyst modified with black phosphorus(BP)nanodots(BPNDs-Pt/C)by using a facile ultrasonic mixing method.Experimental and computational investigations reveal that the electron transfer from BP to Pt leads to weak adsorption of hydroxyl groups on the Pt surface.As a result,the BPNDs-Pt/C catalyst exhibits efficient activity and anti-methanol ability for cathodic oxygen reduction electrocatalysis in an acidic medium.Additionally,it demonstrates high activity for oxygen reduction reaction(ORR)in an alternative alkaline system with cation exchange membrane and eliminable methanol penetration.This work highlights the feasibility of using non-metallic elements to regulate the electronic structure and surface properties of Pt-based nanomaterials.Furthermore,the designed BPNDs-Pt/C electrocatalyst,with controllable ORR performance,can be applied across various scenarios based on demand.
基金supported by the National Key Research and Development Program of China(2022YFA1503602)the National Natural Science Foundation of China(22288101,U21B20101 and 22172141)+1 种基金the BASF International Network of Centers of Excellence projectthe Zhejiang Provincial Natural Science Foundation of China(LR24B030001)。
文摘ITR zeolite could be potentially used as catalysts in methanol to propylene(MTP),where their performance is strongly related to its Al distribution.However,the control of Al distribution in ITR zeolite poses a significant synthetic challenge.Herein,we demonstrate the possibility to control the Al distribution in ITR zeolites using zeolite A as an aluminum source(A-ITR).The A-ITR exhibited similar crystallinity,nanosheet morphology,textual parameters,and acidic concentration with those of conventional ITR made zeolites using aluminum isopropoxide as an aluminum source(C-ITR).Characterizations of the zeolite product with^(27)Al MQ.MAS NMR spectra,^(27)Al MAS NMR spectra,and 1-hexene cracking reveal that the A-ITR zeolites have more Al species distributed in T6 and T8 sites located in relatively smaller micropores of the framework than C-ITR.As a result,the A-ITR gave enhanced catalyst lifetime and propylene selectivity due to the suppression of the aromatic cycle in the MTP reaction,compared with the C-ITR.This work provides an alternative approach to prepare efficient ITR zeolites for MTP reaction.
基金supported by the Youth Autonomous Innovation Funding from Army Engineering University of PLA(KYJBJKQTZQ23005)the Basic Discipline Incubation Funding from Army Engineering University of PLA(KYJBJKQTZK23011).
文摘Based upon the thiophene-2,5-dicarboxylic acid(H_(2)Tdc),a novel[Sc_(3)(μ_(2)-OH)_(3)(CO_(2))_(4)O_(6)]n inorganic chain-based Sc-MOF with decorated nitrate ions,{[Sc_(3)(OH)_(2)(Tdc)_(3)(NO_(3))]⋅H_(2)O}_(∞)(AEU-1;AEU for Army Engineering University of PLA),was synthesized,which shows good water and chemical stabilities.Significantly,due to channel constriction accompanied by the polar window caused by introducing nitrate ions,AEU-1 exhibits high C_(2)H_(6)/C_(2)H_(4)adsorption selectivity comparable to many famous C_(2)H_(6)-selective MOFs,making it a promising candidate for the purification of methanol-to-olefin(MTO)products.Furthermore,theoretical investigations reveal that the introduced nitrate ions in AEU-1 as the main adsorption sites could provide strong interactions between the framework and C2H6/C3H6 in the full-contacting mode,leading to an increase in the adsorption enthalpies(Qst)of C_(2)H_(6)and C_(3)H_(6),and thus further improving the C_(2)H_(6)/C_(2)H_(4)and C_(3)H_(6)/C_(2)H_(4)adsorption selectivity.Our work could open up a new avenue for constructing MOFs with inorganic polar moieties as adsorption sites for one-step C_(2)H_(4)purification and C3H6 recovery from MTO mixtures with high selectivity.
文摘One-step direct production of methanol from methane and water(PMMW)under mild conditions is challenging in heterogeneous catalysis owing to the absence of highly effective catalysts.Herein,we designed a series of“Single-Atom”-“Frustrated Lewis Pair”(SA-FLP)dual active sites for the direct PMMW via density functional theory(DFT)calculations combined with a machine learning(ML)approach.The results indicate that the nine designed SA-FLP catalysts are capable of efficiently activate CH4 and H_(2)O and facilitate the coupling of OH^(*)and CH_(3)^(*)into methanol.The DFT-based microkinetic simulation(MKM)results indicate that CH_(3)OH production on Co1-FLP and Pt1-FLP catalysts can reach the turnover frequencies(TOFs)of 1.01×10^(−3)s^(-1)and 8.80×10^(−4)s^(-1),respectively,which exceed the experimentally reported values by three orders of magnitude.ML results unveil that the gradient boosted regression model with 13 simple features could give satisfactory predictions for the TOFs of CH_(3)OH production with RMSE and R^(2)of 0.009 s^(-1)and 1.00,respectively.The ML-predicted MKM results indicate that four catalysts including V_(1-),Fe_(1-),Ti_(1-),and Mn_(1)-FLP exhibit higher TOFs of CH_(3)OH production than the value that the most relevant experiments reported,indicating that the four catalysts are also promising catalysts for the PMMW.This study not only develops a simple and efficient approach for design and screening SA-FLP catalysts but also provides mechanistic insights into the direct PMMW.
基金supported by the National Key R&D Program of China(2022YFA1504500,2022YFB4003100)the National Natural Science Foundation of China(U21B2092,22072162,22202213,22402210)+1 种基金the International Partnership Program of Chinese Academy of Sciences(172GJHZ2022028MI)Hua Dian Liaoning Energy Development CO.,LTD.(CHDKJ24-04-02-223).
文摘The increasingly serious climate issue compels urgent greenhouse gas mitigation strategies.As a budget,plentiful,renewable feedstock and major contributor to global warming,the large-scale catalytic transformation of CO_(2)has attracted widespread attention from society due to its potential as a solution to the environment and energy crises.At present,catalytic hydrogenation of carbon dioxide to organic chemicals is the primary approach in its industrial applications.In recent decades,various materials containing Cu-,precious metal-,In-,Zn-,and Ga-based catalysts have been designed for CO_(2)hydrogenation to methanol.Likewise,great advances have been made in CO_(2)-to-chemicals,such as olefins,aromatics,and gasoline by combining CO_(2)-to-CH3OH with methanol transformation or tandem reaction of reverse water-gas shift and Fischer-Tropsch(FT)synthesis.This review exhibits the recent advances in the hydrogenation of CO_(2)-to-CH3OH including the catalyst system,CO_(2)activation,nature of active sites,intermediate species(formate or carboxyl),structure-activity relationship,and reaction mechanism.Finally,challenges and outlooks in CO_(2)hydrogenation to methanol are summarized.
基金support by the National Natural Science Foundation of China(Nos.U20A20123,51874357,22379166)Natural Science Foundation for Distinguished Young Scholars of Hunan Province(No.2022JJ10089)。
文摘The sluggish reaction kinetics of the oxygen evolution reaction(OER)and methanol oxidation reaction(MOR)remain obstacles to the commercial promotion of water splitting and direct methanol fuel cells.Considering the vital role of noble metals in electrocatalytic activity,this work focuses on the rational synthesis of Ni-noble metal composite nanocatalysts for overcoming the drawbacks of high cost and susceptible oxidized surfaces of noble metals.The inherent catalytic activity is improved by the altered electronic structure and effective active sites of the catalyst induced by the size effect of noble metal clusters.In particular,a series of Ni-noble metal nanocomposites are successfully synthesized by partially introducing noble metal into Ni with porous interfacial defects derived from Ni-Al layered double hydroxide(LDH).The Ni_(10)Pd_(1)nanocomposite exhibits high OER catalytic activity with an overpotential of 0.279 V at 10 m A/cm^(2),surpassing Ni_(10)Ag_(1)and Ni_(10)Au_(1)counterparts.Furthermore,the average diameter of Pd clusters gradually increases from 5.57 nm to 44.44 nm with the increased proportion of doped Pd,leading to the passivation of catalytic activity due to the exacerbated surface oxidation of Pd in the form of Pd^(2+).After optimization,Ni_(10)Pd_(1)delivers significantly enhanced OER and MOR electroactivities and long-term stability compared to that of Ni_(2)Pd_(1),Ni_(1)Pd_(1)and Ni_(1)Pd_(2),which is conducive to the effective utilization of Pd and alleviation of surface oxidation.
基金supported by the National Natural Science Foundation of China(No.22465009)the Education Department of Guizhou Province(No.2021312)the Foundation of Guizhou Province(No.2019-5666).
文摘Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures(denoted PtPdAu/BiTe)were synthesized using a visible-light-assisted strategy.The coupling alloy and interfacial effects of PtPdAu/BiTe significantly improved the performance and stability of both the ethanol oxidation reaction(EOR)and methanol oxidation reaction(MOR).Introducing a small amount of Au effectively enhanced the CO tolerance of PtPdAu/BiTe compared to dendritic platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures.PtPdAu/BiTe exhibited mass activities of 31.5 and 13.3 A·mg_(Pt)^(-1)in EOR and MOR,respectively,which were 34.4 and 13.2 times higher than those of commercial Pt black,revealing efficient Pt atom utilization.In-situ Fourier transform infrared spectroscopy demonstrated complete 12e^(-)and 6e^(-)oxidation of ethanol and methanol on PtPdAu/BiTe.The PtPdAu/BiTe/C achieved mass peak power densities of 131 and 156 mW·mg_(Pt)^(-1),which were 2.4 and 2.2 times higher than those of Pt/C in practical direct ethanol fuel cell(DEFC)and direct methanol fuel cell(DMFC),respectively,highlighting their potential application in DEFC and DMFC.This study introduces an effective strategy for designing efficient and highly CO tolerant anodic electrocatalysts for practical DEFC and DMFC applications.
文摘Against the backdrop of global energy and environmental crises,the technology of CO_(2)hydrogenation to produce methanol is garnering widespread attention as an innovative carbon capture and utilization solution.Bimetallic oxide catalysts have emerged as the most promising research subject in the field due to their exceptional catalytic performance and stability.The performance of bimetallic oxide catalysts is influenced by multiple factors,including the selection of carrier materials,the addition of promoters,and the synthesis process.Different types of bimetallic oxide catalysts exhibit significant differences in microstructure,surface active sites,and electronic structure,which directly determine the yield and selectivity of methanol.Although bimetallic oxide catalysts offer significant advantages over traditional copper-based catalysts,they still encounter challenges related to activity and cost.In order to enhance catalyst performance,future investigations must delve into microstructure control,surface modification,and reaction kinetics.
