Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups(e.g.,C=C and C=O)is a promising yet challenging endeavor.In our study,we developed a Pd/CeO_(...Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups(e.g.,C=C and C=O)is a promising yet challenging endeavor.In our study,we developed a Pd/CeO_(2) catalyst by enhancing the oxygen vacancy(O V)concentration in CeO_(2) through high-temperature treatment.This process led to the formation of an interface structure ideal for supporting the hydrogenation of methyl oleate to methyl stearate.Specifi cally,metal Pd^(0) atoms bonded to the O V in defective CeO_(2) formed Pd^(0)-O v-Ce^(3+)interfacial sites,enabling strong electron transfer from CeO_(2) to Pd.The interfacial sites exhibit a synergistic adsorption eff ect on the reaction substrate.Pd^(0) sites promote the adsorption and activation of C=C bonds,while O V preferably adsorbs C=O bonds,mitigating competition with C=C bonds for Pd^(0) adsorption sites.This synergy ensures rapid C=C bond activation and accelerates the attack of active H*species on the semi-hydrogenated intermediate.As a result,our Pd/CeO_(2)-500 catalyst,enriched with Pd^(0)-O v-Ce^(3+)interfacial sites,dem-onstrated excellent hydrogenation activity at just 30℃.The catalyst achieved a Cis-C18:1 conversion rate of 99.8% and a methyl stearate formation rate of 5.7 mol/(h·g metal).This work revealed the interfacial sites for enhanced hydrogenation reactions and provided ideas for designing highly active hydrogenation catalysts.展开更多
Directional catalytic transformation of volatile organic compounds(VOCs)into value-added chemicals represents a more sustainable strategy than complete mineralization,as it simultaneously mitigates environmental pollu...Directional catalytic transformation of volatile organic compounds(VOCs)into value-added chemicals represents a more sustainable strategy than complete mineralization,as it simultaneously mitigates environmental pollution and reduces carbon emissions.The primary challenge in achieving multifunctional olefin production from alcohol-type VOCs is the lack of mechanistic clarity,which hinders the targeted synthesis of selective catalysts.Herein,we developed W-Ti hybrid metal oxide catalysts(WTiO_(x))with active Ti-O-W interfaces via a one-step hydrothermal synthesis and demonstrated their effectiveness for isopropanol conversion processes.Remarkably,WTiO_(x)-500 achieved 99.8%isopropanol conversion and 99.3% propylene yield at 140℃,significantly outperforming TiO_(2)(98.4% yield at 180℃)and WO_(3)(90.5% yield at 240℃).WTiO_(x)-500 also displayed higher thermal stability,with isopropanol conversion and propylene yield decreasing by 1.0%and 1.6% after 35 h on-stream reaction.Although impurities(e.g.,CO_(2),HCl,SO_(2))caused partial deactivation of WTiO_(x)-500,oxygen treatment regenerated the catalyst.A series of characterization techniques indicated that the controlled calcination temperature promoted the formation of an optimal Ti-O-Winterface in WTiO_(x)-500 through W substitution into the TiO_(2)lattice and WO_(3)-TiO_(2)surface interaction,where W species effectively tuned the electronic structure.This configuration endowed WTiO_(x)-500 with moderate acidity of BrФnsted(-OH)and Lewis(Ti^(4+)/W^(6+))acid sites,which synergistically facilitated charge transfer between isopropanol and catalyst,accelerated C-O bond cleavage during dehydration.This work provides mechanistic insights into isopropanol dehydration and demonstrates a potential approach for VOC valorization.展开更多
Qualitatively identifying the dominant catalytic site for each step of a semi-continuous reaction and semi-quantitatively correlating such different sites to the catalytic performance is of great significance toward t...Qualitatively identifying the dominant catalytic site for each step of a semi-continuous reaction and semi-quantitatively correlating such different sites to the catalytic performance is of great significance toward the integration of multiple well-optimized sites on a heterogeneous catalyst.Herein,a series of structurally defined TiO_(x)-based catalysts were synthesized to provide a feasible approach to investigate the aforementioned issues using the semi-continuous oxidation of glycerol as a model reaction.Detailed investigations have verified the simultaneous presence of two kinds of Pt active sites:1)Negatively charged Pt bound to the oxygen vacancies of modified TiO_(x)in the form of Pt^(δ−)-O_(v)-Ti^(3+) sites and 2)metallic Pt(Pt_(0)site)located away from the inter-face.Meanwhile,the proportion of surficial and interfacial sites varies over this series of catalysts.Combined in situ FTIR experiments revealed that the reaction network was well-tuned via a site cooperation mechanism:The surficial Pt_(0)sites dissociatively adsorb the OH group of glycerol with a monodentate bonding geometry and the Pt^(δ−)-O_(v)-Ti^(3+) sites dissociate the C=O bond of the aldehyde group in a bidentate form.Furthermore,CO-FTIR spectroscopy confirmed a correlation between the reaction rate/product selectivity and the fraction of surficial/interfacial sites.A rational proportion of surficial and interfacial sites is key to enabling a high yield of glyceric acid.The most active catalyst with 32%surface sites and 68%interfacial sites exhibited 90.0%glycerol conversion and 68.5%GLYA selectivity.These findings provide a deeper understanding of the structure-activity relationships using qualitative identification and semi-quantitative analysis.展开更多
The development of efficient photocatalytic H2-evolution materials requires both rapid electron transfer and an effective interfacial catalysis reaction for H2 production. In addition to the well-known noble metals, l...The development of efficient photocatalytic H2-evolution materials requires both rapid electron transfer and an effective interfacial catalysis reaction for H2 production. In addition to the well-known noble metals, low-cost and earth-abundant non-noble metals can also act as electron- transfer mediators to modify photocatalysts. However, as almost all non-noble metals lack the interfacial catalytic active sites required for the H2-evolution reaction, the enhancement of the photocatalytic performance is limited. Therefore, the development of new interfacial active sites on metal-modified photocatalysts is of considerable importance. In this study, to enhance the photocatalytic evolution of H2 by Ni-modified TiO2, the formation of NiSx as interfacial active sites was promoted on the surface of Ni nanoparticles. Specifically, the co-modified TiO2/Ni-NiSx photocatalysts were prepared via a two-step process involving the photoinduced deposition of Ni on the TiO2 surface and the subsequent formation of NiSx on the Ni surface by a hydrothermal reaction method. It was found that the TiO2/Ni-NiSx photocatalysts exhibited enhanced photocatalytic H2-evolution activity. In particular, TiO2/Ni-NiSx(30%) showed the highest photocatalytic rate (223.74 μmol h.1), which was greater than those of TiO2, TiO2/Ni, and TiO2/NiSx by factors of 22.2, 8.0, and 2.2, respectively. The improved H2-evolution performance of TiO2/Ni-NiSx could be attributed to the excellent synergistic effect of Ni and NiSx, where Ni nanoparticles function as effective mediators to transfer electrons from the TiO2 surface and NiSx serves as interfacial active sites to capture H+ ions from solution and promote the interfacial H2-evolution reaction. The synergistic effect of the non-noble metal cocatalyst and the interfacial active sites may provide new insights for the design of highly efficient photocatalytic materials.展开更多
Designing catalysts with capable dual-active sites to drive catalytic hydrogen generation is necessary for the future hydrogen economy.Herein,the interfacial active sites consisting of Co and Co-C on Co-Co_(2)C@carbon...Designing catalysts with capable dual-active sites to drive catalytic hydrogen generation is necessary for the future hydrogen economy.Herein,the interfacial active sites consisting of Co and Co-C on Co-Co_(2)C@carbon heterostructure are designed through annealing and highpressure carbonization.The operating temperature during the high-pressure carbonization under a CO-reducing environment is responsible for the construction and regulation of Co-Co_(2)C@C heterostructure.The optimal catalyst has a high turnover frequency(TOF) of33.1 min^(-1) and low activation energy(E_a) of27.3 kJ-mol^(-1) during the hydrolysis of NH_(3)BH_(3).The catalytic stability of Co-Co_(2)C@C has no dramatic deterioration even after 5 cyclic usages.The interfacial active sites and the carbon on the catalyst surface enhance hydrogen generation kinetics and catalytic stability.The construction of interfacial active sites in Co-Co_(2)C@C prompts the dissociation of reactants(NH_(3)BH_(3) and H_(2)O molecules),leading to an enhanced catalytic hydrogen generation from NH_(3)BH_(3) hydrolysis(Co activates NH_(3)BH_(3) and Co-C activates H_(2)O).The construction of hetero-structural catalysts provides theoretical direction for the rational design of advanced transition metal carbide materials in the field of energy catalysis and conversion.展开更多
The interaction between the metal and the support of supported metal catalysts, which are widely used in industry, is the primary focus of the study of such catalysts. With the developing understanding of the metal–s...The interaction between the metal and the support of supported metal catalysts, which are widely used in industry, is the primary focus of the study of such catalysts. With the developing understanding of the metal–support interaction, the intrinsic factor that influences the catalytic performance has been determined to be the structure of interfacial sites. Layered double hydroxides(LDHs, a class of two-dimensional layered anion clay) possess several unique characteristics, such as the following:(1) tunable elemental component, homogeneous distribution of metal cations.(2) anchoring eff ect.(3) multiple layered structure for exfoliation or intercalation and special memory eff ect;and(4) internal/external confinement eff ects during topological transformation. Taking LDHs and their derivatives as precursors or supports shows superior advantages in designing interfacial active catalysts with tunable properties. Therefore, this review is mainly focused on constructing interfacial active catalysts by LDHs and revealing the interfacial eff ects(including electronic, geometric, and bifunctional eff ects) on the catalytic performance that will provide new perspectives and approaches for the development of heterogeneous catalysis.展开更多
Tuning the metal-oxide interface to achieve optimal catalytic performance represents a classic yet fast-growing area in catalysis research.This work demonstrated that the decoration of CeO_(2) clusters onto Ni particl...Tuning the metal-oxide interface to achieve optimal catalytic performance represents a classic yet fast-growing area in catalysis research.This work demonstrated that the decoration of CeO_(2) clusters onto Ni particles creates electron-enriched Ni sites at the Ni-CeO_(2) interface with highly efficient CO methanation,by kinetics,chemical titration,and a series of in situ/operando spectroscopic characterizations.These electron-enriched Ni atoms facilitate the back-donation of electrons into the orbital of CO and thus reduce the reaction barrier of CH_(4) formation,but do not alter the catalytic steps and their kinetic relevance as well as the evolution of surface intermediates during CO methanation.The amount of electron-enriched Ni atoms increases significantly to a maximum value and then decreases as the content of CeO_(2) increases,leading the formation rates of CH_(4) to increase in a volcano-type relation with CeO_(2) contents in xCeNi/Al_(2)O_(3) catalysts.These insights provide a comprehensive understanding of the nature and the role of the metal-oxide interface and could potentially guide the rational design of highly efficient oxide-supported catalysts for CO methanation.展开更多
Transforming CO_(2)into long-chain hydrocarbons that can be used in the current energy and chemical sectors is a promising pathway toward a circular carbon economy.However,the direct conversion of CO_(2)into C_(5+)hyd...Transforming CO_(2)into long-chain hydrocarbons that can be used in the current energy and chemical sectors is a promising pathway toward a circular carbon economy.However,the direct conversion of CO_(2)into C_(5+)hydrocarbons over Co-based catalysts is significantly challenging owing to the inherent high methanation activities of these catalysts.Herein,the incorporation of oxygen vacancy-containing ZrO_(2)into a Co-based catalyst is demonstrated to increase C_(5+)yields up to 26.9%by suppressing the CH_(4)selectivity at 270℃.The Na-and ZrO_(2)-promoted Co catalyst(Na-CoZrO_(x)-8)exhibited highly stable CO_(2)hydrogenation performance during a 2100 h on-stream reaction.In situ-formed Co^(0) core and ZrO_(2)shell structure inhibited Co particle agglomeration and maintained the structural integrity of the catalyst during CO_(2)hydrogenation.Preferential adsorption of CO at the ZrO_(2)-Co interfacial site facilitated CO dissociation,ultimately increasing the C_(5+)selectivity.Reaction mechanism analysis by an operando in situ study revealed a carbonate pathway for the reverse water gas shift reaction and H-assisted CO dissociation for the Fischer-Tropsch synthesis to produce C_(5+)over Na-CoZrO_(x)-8.展开更多
To obtain environmentally friendly,integrated and miniaturized gas sensors for the increasing request for the Internet of Things industry and other relative areas,the ultra-thin CoO_(x)/Zn O heterogeneous film with ac...To obtain environmentally friendly,integrated and miniaturized gas sensors for the increasing request for the Internet of Things industry and other relative areas,the ultra-thin CoO_(x)/Zn O heterogeneous film with active interfacial sites was in-situ deposited on micro-electro-mechanical systems(MEMS)as H_(2)S sensor.Atomic layer deposition(ALD)was employed to in-situ fabricate the uniform Zn O thin film.ALD CoO_(x)was deposited on ZnO surface to obtain CoO_(x)/Zn O heterojunction and active interfacial sites.The ultra-thin film(20 nm)with 50 ALD Co O_(x)decorated on 250 ALD Zn O displays excellent sensing performance,including very high response(4.45@200×10^(-9))and selectivity to H_(2)S with a limit of detection(LOD)of 0.38×10^(-9),long-term sensing stability,high response/recovery performance(7.5 s/15.7 s)and mechanical strength at 230。C.Reasons for the high sensing performance of CoO_(x)/Zn O have been confirmed by series of characterizations and density functional theory(DFT)calculation.Heterojunction film thickness with Debye length,the oxygen vacancies and the synergistic effect of active interfacial sites are main reasons for the high sensing performance.The strategy by fabrication of CoO_(x)/Zn O heterogeneous film within Debye length and employing synergistic effect of active interfacial sites offers a promising route for the design of environmentally friendly gas sensors.Furthermore,the ALD technique offers a facile in-situ strategy and high-throughput fabrication of MEMS gas sensors.展开更多
The hydrogen evolution reaction(HER)of molybdenum disulfide(MoS_(2))is limited in alkaline and acid solution because the active sites are on the finite edge with extended basal plane remaining inert.Herein,we activate...The hydrogen evolution reaction(HER)of molybdenum disulfide(MoS_(2))is limited in alkaline and acid solution because the active sites are on the finite edge with extended basal plane remaining inert.Herein,we activated the interfacial S sites by coupling with Ru nanoparticles on the inert basal plane of MoS_(2)nanosheets.The density functional theory(DFT)calculation and experimental results show that the interfacial S electronic structure was modulated.And the results of∆G H*demonstrate that the adsorption of H on the MoS_(2)was also optimized.With the advantage of interfacial S sites activation,the Ru-MoS_(2)needs only overpotential of 110 and 98 mV to achieve 10 mA·cm^(–2)in both 0.5 M H_(2)SO_(4)and ^(1) M KOH solution,respectively.This strategy paves a new way for activating the basal plane of other transition metal sulfide electrocatalysts for improving the HER performance.展开更多
Silver‐modified semiconductor photocatalysts typically exhibit enhanced photocatalytic activitytoward the degradation of organic substances.In comparison,their hydrogen‐evolution rates arerelatively low owing to poo...Silver‐modified semiconductor photocatalysts typically exhibit enhanced photocatalytic activitytoward the degradation of organic substances.In comparison,their hydrogen‐evolution rates arerelatively low owing to poor interfacial catalytic reactions to producing hydrogen.In the presentstudy,thiocyanate anions(SCN–)as interfacial catalytic active sites were selectively adsorbed ontothe Ag surface of g‐C3N4/Ag photocatalyst to promote interfacial H2‐evolution reactions.The thiocyanate‐modified g‐C3N4/Ag(g‐C3N4/Ag‐SCN)photocatalysts were synthesized via photodepositionof metallic Ag on g‐C3N4and subsequent selective adsorption of SCN– ions on the Ag surface by animpregnation method.The resulting g‐C3N4/Ag‐SCN photocatalysts exhibited considerably higherphotocatalytic H2‐evolution activity than the g‐C3N4,g‐C3N4/Ag,and g‐C3N4/SCN photocatalysts.Furthermore,the g‐C3N4/Ag‐SCN photocatalyst displayed the highest H2‐evolution rate(3.9μmolh?1)when the concentration of the SCN– ions was adjusted to0.3mmol L?1.The H2‐evolution rateobtained was higher than those of g‐C3N4(0.15μmol h?1)and g‐C3N4/Ag(0.71μmol h?1).Consideringthe enhanced performance of g‐C3N4/Ag upon minimal addition of SCN– ions,a synergistic effectof metallic Ag and SCN– ions is proposed―the Ag nanoparticles act as an effective electron‐transfermediator for the steady capture and rapid transportation of photogenerated electrons,while theadsorbed SCN– ions serve as an interfacial active site to effectively absorb protons from solution andpromote rapid interfacial H2‐evolution reactions.Considering the present facile synthesis and itshigh efficacy,the present work may provide new insights into preparing high‐performance photocatalytic materials展开更多
Interfacial engineering is a promising approach for enhancing electrochemical performance,but rich and efficient interfacial active sites remain a challenge in fabrication.Herein,RuO_(2)-PdO heterostructure nanowire n...Interfacial engineering is a promising approach for enhancing electrochemical performance,but rich and efficient interfacial active sites remain a challenge in fabrication.Herein,RuO_(2)-PdO heterostructure nanowire networks(NWs) with rich interfaces and defects supported on carbon(RuO_(2)-PdO NWs/C) for alkaline hydrogen oxidation reaction(HOR) was formed by a seed induction-oriented attachment-thermal treatment method for the first time.As expected,the RuO_(2)-PdO NWs/C(72.8% Ru atomic content in metal) exhibits an excellent activity in alkaline HOR with a mass specific exchange current density(jo,m) of 1061 A gRuPd-1,which is 3.1 times of commercial Pt/C and better than most of the reported nonPt noble metal HOR electrocatalysts.Even at the high potential(~0.5 V vs.RHE) or the presence of CO(5 vol%),the RuO_(2)-PdO NWs/C still effectively catalyzes the alkaline HOR.Structure/electrochemical analysis and theoretical calculations reveal that the interfaces between RuO_(2) and PdO act as the active sites.The electronic interactions between the two species and the rich defects for the interfacial active sites weaken the adsorption of Had,also strengthen the adsorption of OHad,and accelerate the alkaline HOR process.Moreover,OHadon RuO_(2) can spillover to the interfaces,keeping the RuO_(2)-PdO NWs/C with the stable current density at higher potential and high resistance to CO poisoning.展开更多
Cu-based catalysts have been extensively used in methanol steam reforming(MSR)reactions because of their low cost and high effi ciency.ZnO is often used in commercial Cu-based catalysts as both a structural and an ele...Cu-based catalysts have been extensively used in methanol steam reforming(MSR)reactions because of their low cost and high effi ciency.ZnO is often used in commercial Cu-based catalysts as both a structural and an electronic promoter to stabilize metal Cu nanoparticles and modify metal–support interfaces.Still,the further addition of chemical promoters is essential to further enhance the MSR reaction performance of the Cu/ZnO catalyst.In this work,CeO_(2)-doped Cu/ZnO catalysts were prepared using the coprecipitation method,and the eff ects of CeO_(2)on Cu-based catalysts were systematically investigated.Doping with appropriate CeO_(2)amounts could stabilize small Cu nanoparticles through a strong interaction between CeO_(2)and Cu,leading to the formation of more Cu+–ZnO x interfacial sites.However,higher CeO_(2)contents resulted in the formation of larger Cu nanoparticles and an excess of Cu+–CeO x interfacial sites.Consequently,the Cu/5CeO_(2)/ZnO catalyst with maximal Cu–ZnO interfaces exhibited the highest H 2 production rate of 94.6 mmolH2/(gcat·h),which was 1.5 and 10.2 times higher than those of Cu/ZnO and Cu/CeO_(2),respectively.展开更多
The reverse water−gas shift(RWGS)reaction is a key process for CO_(2) conversion and sustainable fuel production,yet the nature of the active sites on Pt/TiO_(2) cluster catalysts remains elusive.Using first-principle...The reverse water−gas shift(RWGS)reaction is a key process for CO_(2) conversion and sustainable fuel production,yet the nature of the active sites on Pt/TiO_(2) cluster catalysts remains elusive.Using first-principles microkinetic simulations,we systematically investigated the catalytic behavior of Pt clusters on TiO_(2) under operational reaction conditions.We studied three distinct catalytic sites-Pt cluster surfaces,oxygen vacancies(O_(V))on TiO_(2),and Pt−O_(V)−Ti interfaces-and revealed that the Pt−O_(V)−Ti interface exhibited the highest RWGS activity via a redox mechanism.This synergy enhances CO_(2) activation and facilitates oxygen reduction more effectively than the isolated O_(V) on TiO_(2),which show 4-fold lower activity.In contrast,CO-covered Pt clusters show minimal CO_(2) activation but serve as H2 dissociation sites,enabling hydrogen spillover to adjacent O_(V) on TiO_(2),thereby sustaining the RWGS process.Kinetic analysis revealed OH reduction to H2O as the rate-determining step on both interfacial Pt−O_(V)−Ti and at the O_(V) on the TiO_(2)−X support.These findings highlight the pivotal role of the Pt−O_(V)−Ti interface in driving the RWGS and offer a design strategy for optimizing high-temperature CO_(2) hydrogenation catalysts by maximizing the number of interfacial active sites.展开更多
Metal oxide supported metal catalysts show promising catalytic performance in many industry-relevant reactions.However,the enhancement of performance is often limited by the insufficient metal/metal oxide interface.In...Metal oxide supported metal catalysts show promising catalytic performance in many industry-relevant reactions.However,the enhancement of performance is often limited by the insufficient metal/metal oxide interface.In this work,we demonstrate a general synthesis of Pt-early transition metal oxide(Pt-MO_(x),M=Ti,Zr,V,and Y)catalysts with rich interfacial sites,which is based on the air-induced surface segregation and oxidation of M in the supported Pt-M alloy catalysts.Systematic characterizations verify the dynamic structural response of Pt-M alloy catalysts to air and the formation of Pt-MO_(x) catalysts with abundant interfacial sites.The prepared Pt-TiO_(x) interfacial catalysts exhibit improved performance in hydrogenation reactions of benzaldehyde,nitrobenzene,styrene,and furfural,as a result of the heterolytic dissociation of H_(2) at Pt-metal oxide interfacial sites.展开更多
Metal oxide-promoted Rh-based catalysts have been widely used for CO2hydrogenation,especially for the ethanol synthesis.However,this reaction usually suffers low CO2conversion and alcohols selectivity due to the forma...Metal oxide-promoted Rh-based catalysts have been widely used for CO2hydrogenation,especially for the ethanol synthesis.However,this reaction usually suffers low CO2conversion and alcohols selectivity due to the formation of byproducts methane and CO.This paper describes an efficient vanadium oxide promoted Rh-based catalysts confined in mesopore MCM-41.The Rh-0.3VOx/MCM-41 catalyst shows superior conversion(~12%)and ethanol selectivity(~24%)for CO2hydrogenation.The promoting effect can be attributed to the synergism of high Rh dispersion by the confinement effect of MCM-41 and the formation of VOx-Rh interface sites.Experimental and theoretical results indicate the formation of til-CO at VOx-Rh interface sites is easily dissociated into*CHx,and then*CHxcan be inserted by CO to form CH3CO*,followed by CH3CO*hydrogenation to ethanol.展开更多
One-dimensional titanium dioxide nanorod(TNR)-supported Cu catalysts(2.5 wt.%-12.5 wt.%)were synthesized using deposition-precipitation.X-ray photoelectron spectroscopy,temperature programmed reduction and CO chemisor...One-dimensional titanium dioxide nanorod(TNR)-supported Cu catalysts(2.5 wt.%-12.5 wt.%)were synthesized using deposition-precipitation.X-ray photoelectron spectroscopy,temperature programmed reduction and CO chemisorption measurements showed that Cu doping over TNR offered metal-support interactions and interfacial active sites that had a profound impact on the catalytic performance.The role of the Cu-TNR interface was investigated by comparing the catalytic activity of Cu-TNR catalysts with that of pure CuO nanoparticles in CO oxidation.The presence of highly dispersed copper species,a high number of interfacial active sites,CO adsorption capacity and surface/lattice oxygen were found to be responsible for the excellent activity of 7.5CU-TNR(ie,Cu loading of 7.5 wt.%on TNR).Moreover,the Cu-TNR catalysts followed the Langmuir-Hinshelwood reaction mechanism with 7.5CU-TNR,exhibiting an apparent activation energy of 44.7 kJ/mol.The TNR-supported Cu catalyst gave the highest interfacial catalytic activity in medium-temperature CO oxidation(120-240℃)compared to other commonly used supports,including titanium dioxide nanoparticles(TiO2-P25),silica(SiO2)and alumina(Al20g)in which copper species were nonhomogeneously dispersed.This study confirms that medium-temperature CO oxidation is highly sensitive to the morphology and structure of the supporting material.展开更多
The strong metal-support interaction(SMSI)in supported catalysts plays a dominant role in catalytic degradation,upgrading,and remanufacturing of environmental pollutants.Previous studies have shown that SMSI is crucia...The strong metal-support interaction(SMSI)in supported catalysts plays a dominant role in catalytic degradation,upgrading,and remanufacturing of environmental pollutants.Previous studies have shown that SMSI is crucial in supported catalysts'activity and stability.However,for redox reactions catalyzed in environmental catalysis,the enhancement mechanism of SMSI-induced oxygen vacancy and electron transfer needs to be clarified.Additionally,the precise control of SMSI interface sites remains to be fully understood.Here we provide a systematic review of SMSI's catalytic mechanisms and control strategies in purifying gaseous pollutants,treating organic wastewater,and valorizing biomass solid waste.We explore the adsorption and activation mechanisms of SMSI in redox reactions by examining interfacial electron transfer,interfacial oxygen vacancy,and interfacial acidic sites.Furthermore,we develop a precise regulation strategy of SMSI from systematical perspectives of interface effect,crystal facet effect,size effect,vip ion doping,and modification effect.Importantly,we point out the drawbacks and breakthrough directions for SMSI regulation in environmental catalysis,including partial encapsulation strategy,size optimization strategy,interface oxygen vacancy strategy,and multi-component strategy.This review article provides the potential applications of SMSI and offers guidance for its controlled regulation in environmental catalysis.展开更多
基金This work was supported by the National Key Research and Development Program of China(No.2023YFB4203800).
文摘Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups(e.g.,C=C and C=O)is a promising yet challenging endeavor.In our study,we developed a Pd/CeO_(2) catalyst by enhancing the oxygen vacancy(O V)concentration in CeO_(2) through high-temperature treatment.This process led to the formation of an interface structure ideal for supporting the hydrogenation of methyl oleate to methyl stearate.Specifi cally,metal Pd^(0) atoms bonded to the O V in defective CeO_(2) formed Pd^(0)-O v-Ce^(3+)interfacial sites,enabling strong electron transfer from CeO_(2) to Pd.The interfacial sites exhibit a synergistic adsorption eff ect on the reaction substrate.Pd^(0) sites promote the adsorption and activation of C=C bonds,while O V preferably adsorbs C=O bonds,mitigating competition with C=C bonds for Pd^(0) adsorption sites.This synergy ensures rapid C=C bond activation and accelerates the attack of active H*species on the semi-hydrogenated intermediate.As a result,our Pd/CeO_(2)-500 catalyst,enriched with Pd^(0)-O v-Ce^(3+)interfacial sites,dem-onstrated excellent hydrogenation activity at just 30℃.The catalyst achieved a Cis-C18:1 conversion rate of 99.8% and a methyl stearate formation rate of 5.7 mol/(h·g metal).This work revealed the interfacial sites for enhanced hydrogenation reactions and provided ideas for designing highly active hydrogenation catalysts.
基金supported by the National Natural Science Foundation of China(U23A20120 and 22425601)National Key R&D Program of China(2023YFB3810801)+2 种基金Natural Science Foundation of Hebei Province(B2021208033)Beijing Nova Program(20240484659)R&D Program of Beijing Municipal Education Commission(KZ202210005011).
文摘Directional catalytic transformation of volatile organic compounds(VOCs)into value-added chemicals represents a more sustainable strategy than complete mineralization,as it simultaneously mitigates environmental pollution and reduces carbon emissions.The primary challenge in achieving multifunctional olefin production from alcohol-type VOCs is the lack of mechanistic clarity,which hinders the targeted synthesis of selective catalysts.Herein,we developed W-Ti hybrid metal oxide catalysts(WTiO_(x))with active Ti-O-W interfaces via a one-step hydrothermal synthesis and demonstrated their effectiveness for isopropanol conversion processes.Remarkably,WTiO_(x)-500 achieved 99.8%isopropanol conversion and 99.3% propylene yield at 140℃,significantly outperforming TiO_(2)(98.4% yield at 180℃)and WO_(3)(90.5% yield at 240℃).WTiO_(x)-500 also displayed higher thermal stability,with isopropanol conversion and propylene yield decreasing by 1.0%and 1.6% after 35 h on-stream reaction.Although impurities(e.g.,CO_(2),HCl,SO_(2))caused partial deactivation of WTiO_(x)-500,oxygen treatment regenerated the catalyst.A series of characterization techniques indicated that the controlled calcination temperature promoted the formation of an optimal Ti-O-Winterface in WTiO_(x)-500 through W substitution into the TiO_(2)lattice and WO_(3)-TiO_(2)surface interaction,where W species effectively tuned the electronic structure.This configuration endowed WTiO_(x)-500 with moderate acidity of BrФnsted(-OH)and Lewis(Ti^(4+)/W^(6+))acid sites,which synergistically facilitated charge transfer between isopropanol and catalyst,accelerated C-O bond cleavage during dehydration.This work provides mechanistic insights into isopropanol dehydration and demonstrates a potential approach for VOC valorization.
基金This work was supported by the National Natural Science Foundation(Grants No.22022801,21878016)the National Key Research and Development Program of China(Grant No.2017YFA0206804)Fundamental Research Funds for the Central Universities.
文摘Qualitatively identifying the dominant catalytic site for each step of a semi-continuous reaction and semi-quantitatively correlating such different sites to the catalytic performance is of great significance toward the integration of multiple well-optimized sites on a heterogeneous catalyst.Herein,a series of structurally defined TiO_(x)-based catalysts were synthesized to provide a feasible approach to investigate the aforementioned issues using the semi-continuous oxidation of glycerol as a model reaction.Detailed investigations have verified the simultaneous presence of two kinds of Pt active sites:1)Negatively charged Pt bound to the oxygen vacancies of modified TiO_(x)in the form of Pt^(δ−)-O_(v)-Ti^(3+) sites and 2)metallic Pt(Pt_(0)site)located away from the inter-face.Meanwhile,the proportion of surficial and interfacial sites varies over this series of catalysts.Combined in situ FTIR experiments revealed that the reaction network was well-tuned via a site cooperation mechanism:The surficial Pt_(0)sites dissociatively adsorb the OH group of glycerol with a monodentate bonding geometry and the Pt^(δ−)-O_(v)-Ti^(3+) sites dissociate the C=O bond of the aldehyde group in a bidentate form.Furthermore,CO-FTIR spectroscopy confirmed a correlation between the reaction rate/product selectivity and the fraction of surficial/interfacial sites.A rational proportion of surficial and interfacial sites is key to enabling a high yield of glyceric acid.The most active catalyst with 32%surface sites and 68%interfacial sites exhibited 90.0%glycerol conversion and 68.5%GLYA selectivity.These findings provide a deeper understanding of the structure-activity relationships using qualitative identification and semi-quantitative analysis.
基金supported by the National Natural Science Foundation of China(21477094)the Fundamental Research Funds for the Central Universities(WUT 2017IB002)~~
文摘The development of efficient photocatalytic H2-evolution materials requires both rapid electron transfer and an effective interfacial catalysis reaction for H2 production. In addition to the well-known noble metals, low-cost and earth-abundant non-noble metals can also act as electron- transfer mediators to modify photocatalysts. However, as almost all non-noble metals lack the interfacial catalytic active sites required for the H2-evolution reaction, the enhancement of the photocatalytic performance is limited. Therefore, the development of new interfacial active sites on metal-modified photocatalysts is of considerable importance. In this study, to enhance the photocatalytic evolution of H2 by Ni-modified TiO2, the formation of NiSx as interfacial active sites was promoted on the surface of Ni nanoparticles. Specifically, the co-modified TiO2/Ni-NiSx photocatalysts were prepared via a two-step process involving the photoinduced deposition of Ni on the TiO2 surface and the subsequent formation of NiSx on the Ni surface by a hydrothermal reaction method. It was found that the TiO2/Ni-NiSx photocatalysts exhibited enhanced photocatalytic H2-evolution activity. In particular, TiO2/Ni-NiSx(30%) showed the highest photocatalytic rate (223.74 μmol h.1), which was greater than those of TiO2, TiO2/Ni, and TiO2/NiSx by factors of 22.2, 8.0, and 2.2, respectively. The improved H2-evolution performance of TiO2/Ni-NiSx could be attributed to the excellent synergistic effect of Ni and NiSx, where Ni nanoparticles function as effective mediators to transfer electrons from the TiO2 surface and NiSx serves as interfacial active sites to capture H+ ions from solution and promote the interfacial H2-evolution reaction. The synergistic effect of the non-noble metal cocatalyst and the interfacial active sites may provide new insights for the design of highly efficient photocatalytic materials.
基金financially supported by the National Natural Science Foundation of China (Nos.52071135, 51871090 and U1804135)the Fundamental Research Funds for the Universities of Henan Province (Nos.NSFRF220201 and NSFRF200402)。
文摘Designing catalysts with capable dual-active sites to drive catalytic hydrogen generation is necessary for the future hydrogen economy.Herein,the interfacial active sites consisting of Co and Co-C on Co-Co_(2)C@carbon heterostructure are designed through annealing and highpressure carbonization.The operating temperature during the high-pressure carbonization under a CO-reducing environment is responsible for the construction and regulation of Co-Co_(2)C@C heterostructure.The optimal catalyst has a high turnover frequency(TOF) of33.1 min^(-1) and low activation energy(E_a) of27.3 kJ-mol^(-1) during the hydrolysis of NH_(3)BH_(3).The catalytic stability of Co-Co_(2)C@C has no dramatic deterioration even after 5 cyclic usages.The interfacial active sites and the carbon on the catalyst surface enhance hydrogen generation kinetics and catalytic stability.The construction of interfacial active sites in Co-Co_(2)C@C prompts the dissociation of reactants(NH_(3)BH_(3) and H_(2)O molecules),leading to an enhanced catalytic hydrogen generation from NH_(3)BH_(3) hydrolysis(Co activates NH_(3)BH_(3) and Co-C activates H_(2)O).The construction of hetero-structural catalysts provides theoretical direction for the rational design of advanced transition metal carbide materials in the field of energy catalysis and conversion.
基金supported by the National Natural Science Foundation(Nos.22022801,21878016)National Key Research and Development Program of China(No.2016YFB0301601)the Fundamental Research Funds for the Central Universities(Nos.BHYC1701B,JD2004)。
文摘The interaction between the metal and the support of supported metal catalysts, which are widely used in industry, is the primary focus of the study of such catalysts. With the developing understanding of the metal–support interaction, the intrinsic factor that influences the catalytic performance has been determined to be the structure of interfacial sites. Layered double hydroxides(LDHs, a class of two-dimensional layered anion clay) possess several unique characteristics, such as the following:(1) tunable elemental component, homogeneous distribution of metal cations.(2) anchoring eff ect.(3) multiple layered structure for exfoliation or intercalation and special memory eff ect;and(4) internal/external confinement eff ects during topological transformation. Taking LDHs and their derivatives as precursors or supports shows superior advantages in designing interfacial active catalysts with tunable properties. Therefore, this review is mainly focused on constructing interfacial active catalysts by LDHs and revealing the interfacial eff ects(including electronic, geometric, and bifunctional eff ects) on the catalytic performance that will provide new perspectives and approaches for the development of heterogeneous catalysis.
文摘Tuning the metal-oxide interface to achieve optimal catalytic performance represents a classic yet fast-growing area in catalysis research.This work demonstrated that the decoration of CeO_(2) clusters onto Ni particles creates electron-enriched Ni sites at the Ni-CeO_(2) interface with highly efficient CO methanation,by kinetics,chemical titration,and a series of in situ/operando spectroscopic characterizations.These electron-enriched Ni atoms facilitate the back-donation of electrons into the orbital of CO and thus reduce the reaction barrier of CH_(4) formation,but do not alter the catalytic steps and their kinetic relevance as well as the evolution of surface intermediates during CO methanation.The amount of electron-enriched Ni atoms increases significantly to a maximum value and then decreases as the content of CeO_(2) increases,leading the formation rates of CH_(4) to increase in a volcano-type relation with CeO_(2) contents in xCeNi/Al_(2)O_(3) catalysts.These insights provide a comprehensive understanding of the nature and the role of the metal-oxide interface and could potentially guide the rational design of highly efficient oxide-supported catalysts for CO methanation.
基金funded by the National Research Council of Science&Technology(NST)grant from the Ministry of Science and ICT(MSIT),Republic of Korea(No.CAP21012-100)Korea Institute of Energy Technology Evaluation and Planning(KETEP)under the Ministry of Trade,Industry&Energy(MOTIE),Republic of Korea(No.20224C10300010)additional funding from the KETEP grant,MOTIE(20224000000440,Sector Coupling Energy Industry Advancement Manpower Training Program)。
文摘Transforming CO_(2)into long-chain hydrocarbons that can be used in the current energy and chemical sectors is a promising pathway toward a circular carbon economy.However,the direct conversion of CO_(2)into C_(5+)hydrocarbons over Co-based catalysts is significantly challenging owing to the inherent high methanation activities of these catalysts.Herein,the incorporation of oxygen vacancy-containing ZrO_(2)into a Co-based catalyst is demonstrated to increase C_(5+)yields up to 26.9%by suppressing the CH_(4)selectivity at 270℃.The Na-and ZrO_(2)-promoted Co catalyst(Na-CoZrO_(x)-8)exhibited highly stable CO_(2)hydrogenation performance during a 2100 h on-stream reaction.In situ-formed Co^(0) core and ZrO_(2)shell structure inhibited Co particle agglomeration and maintained the structural integrity of the catalyst during CO_(2)hydrogenation.Preferential adsorption of CO at the ZrO_(2)-Co interfacial site facilitated CO dissociation,ultimately increasing the C_(5+)selectivity.Reaction mechanism analysis by an operando in situ study revealed a carbonate pathway for the reverse water gas shift reaction and H-assisted CO dissociation for the Fischer-Tropsch synthesis to produce C_(5+)over Na-CoZrO_(x)-8.
基金financially supported by the National Key Research and Development Program of China(No.2020YFB2008600)the financial support from China Scholarship Council(CSC)。
文摘To obtain environmentally friendly,integrated and miniaturized gas sensors for the increasing request for the Internet of Things industry and other relative areas,the ultra-thin CoO_(x)/Zn O heterogeneous film with active interfacial sites was in-situ deposited on micro-electro-mechanical systems(MEMS)as H_(2)S sensor.Atomic layer deposition(ALD)was employed to in-situ fabricate the uniform Zn O thin film.ALD CoO_(x)was deposited on ZnO surface to obtain CoO_(x)/Zn O heterojunction and active interfacial sites.The ultra-thin film(20 nm)with 50 ALD Co O_(x)decorated on 250 ALD Zn O displays excellent sensing performance,including very high response(4.45@200×10^(-9))and selectivity to H_(2)S with a limit of detection(LOD)of 0.38×10^(-9),long-term sensing stability,high response/recovery performance(7.5 s/15.7 s)and mechanical strength at 230。C.Reasons for the high sensing performance of CoO_(x)/Zn O have been confirmed by series of characterizations and density functional theory(DFT)calculation.Heterojunction film thickness with Debye length,the oxygen vacancies and the synergistic effect of active interfacial sites are main reasons for the high sensing performance.The strategy by fabrication of CoO_(x)/Zn O heterogeneous film within Debye length and employing synergistic effect of active interfacial sites offers a promising route for the design of environmentally friendly gas sensors.Furthermore,the ALD technique offers a facile in-situ strategy and high-throughput fabrication of MEMS gas sensors.
基金the National Natural Science Foundation of China(Nos.51871078 and 52071119)Heilongjiang Science Foundation(No.E201808).
文摘The hydrogen evolution reaction(HER)of molybdenum disulfide(MoS_(2))is limited in alkaline and acid solution because the active sites are on the finite edge with extended basal plane remaining inert.Herein,we activated the interfacial S sites by coupling with Ru nanoparticles on the inert basal plane of MoS_(2)nanosheets.The density functional theory(DFT)calculation and experimental results show that the interfacial S electronic structure was modulated.And the results of∆G H*demonstrate that the adsorption of H on the MoS_(2)was also optimized.With the advantage of interfacial S sites activation,the Ru-MoS_(2)needs only overpotential of 110 and 98 mV to achieve 10 mA·cm^(–2)in both 0.5 M H_(2)SO_(4)and ^(1) M KOH solution,respectively.This strategy paves a new way for activating the basal plane of other transition metal sulfide electrocatalysts for improving the HER performance.
基金supported by the National Natural Science Foundation of China(51472192,21477094,21771142)the Fundamental Research Funds for the Central Universities(WUT 2017IB002)~~
文摘Silver‐modified semiconductor photocatalysts typically exhibit enhanced photocatalytic activitytoward the degradation of organic substances.In comparison,their hydrogen‐evolution rates arerelatively low owing to poor interfacial catalytic reactions to producing hydrogen.In the presentstudy,thiocyanate anions(SCN–)as interfacial catalytic active sites were selectively adsorbed ontothe Ag surface of g‐C3N4/Ag photocatalyst to promote interfacial H2‐evolution reactions.The thiocyanate‐modified g‐C3N4/Ag(g‐C3N4/Ag‐SCN)photocatalysts were synthesized via photodepositionof metallic Ag on g‐C3N4and subsequent selective adsorption of SCN– ions on the Ag surface by animpregnation method.The resulting g‐C3N4/Ag‐SCN photocatalysts exhibited considerably higherphotocatalytic H2‐evolution activity than the g‐C3N4,g‐C3N4/Ag,and g‐C3N4/SCN photocatalysts.Furthermore,the g‐C3N4/Ag‐SCN photocatalyst displayed the highest H2‐evolution rate(3.9μmolh?1)when the concentration of the SCN– ions was adjusted to0.3mmol L?1.The H2‐evolution rateobtained was higher than those of g‐C3N4(0.15μmol h?1)and g‐C3N4/Ag(0.71μmol h?1).Consideringthe enhanced performance of g‐C3N4/Ag upon minimal addition of SCN– ions,a synergistic effectof metallic Ag and SCN– ions is proposed―the Ag nanoparticles act as an effective electron‐transfermediator for the steady capture and rapid transportation of photogenerated electrons,while theadsorbed SCN– ions serve as an interfacial active site to effectively absorb protons from solution andpromote rapid interfacial H2‐evolution reactions.Considering the present facile synthesis and itshigh efficacy,the present work may provide new insights into preparing high‐performance photocatalytic materials
基金supported by the National Natural Science Foundation of China (22262018)Young Science and Technology Fund in Gansu Province of China (21JR7RA252)+2 种基金Natural Research Fund of Gansu Province (20JR5RA441)Lanzhou Open Competition Mechanism,Merit Based Admission Project Major Fund (2021-JB-6)National Engineering&Fund for National Nickel and Cobalt Advanced Materials Engineering Research Center(GCZX2021JSKF001)。
文摘Interfacial engineering is a promising approach for enhancing electrochemical performance,but rich and efficient interfacial active sites remain a challenge in fabrication.Herein,RuO_(2)-PdO heterostructure nanowire networks(NWs) with rich interfaces and defects supported on carbon(RuO_(2)-PdO NWs/C) for alkaline hydrogen oxidation reaction(HOR) was formed by a seed induction-oriented attachment-thermal treatment method for the first time.As expected,the RuO_(2)-PdO NWs/C(72.8% Ru atomic content in metal) exhibits an excellent activity in alkaline HOR with a mass specific exchange current density(jo,m) of 1061 A gRuPd-1,which is 3.1 times of commercial Pt/C and better than most of the reported nonPt noble metal HOR electrocatalysts.Even at the high potential(~0.5 V vs.RHE) or the presence of CO(5 vol%),the RuO_(2)-PdO NWs/C still effectively catalyzes the alkaline HOR.Structure/electrochemical analysis and theoretical calculations reveal that the interfaces between RuO_(2) and PdO act as the active sites.The electronic interactions between the two species and the rich defects for the interfacial active sites weaken the adsorption of Had,also strengthen the adsorption of OHad,and accelerate the alkaline HOR process.Moreover,OHadon RuO_(2) can spillover to the interfaces,keeping the RuO_(2)-PdO NWs/C with the stable current density at higher potential and high resistance to CO poisoning.
基金This work was supported by the National Key R&D Program of China(2022YFB3805504),National Natural Science Foundation of China(22078089)China Postdoctoral Science Foundation(2023M731081)+3 种基金Shanghai Pilot Program for Basic Research(22TQ1400100-7)the Basic Research Program of Science and Technology Commission of Shanghai Municipality(22JC1400600)Open Foundation of Shanghai Jiao Tong University Shaoxing Research Institute of Renewable Energy and Molecular Engineering(Grant No.JDSX2022046)Shanghai Super Postdoctoral Fellow.
文摘Cu-based catalysts have been extensively used in methanol steam reforming(MSR)reactions because of their low cost and high effi ciency.ZnO is often used in commercial Cu-based catalysts as both a structural and an electronic promoter to stabilize metal Cu nanoparticles and modify metal–support interfaces.Still,the further addition of chemical promoters is essential to further enhance the MSR reaction performance of the Cu/ZnO catalyst.In this work,CeO_(2)-doped Cu/ZnO catalysts were prepared using the coprecipitation method,and the eff ects of CeO_(2)on Cu-based catalysts were systematically investigated.Doping with appropriate CeO_(2)amounts could stabilize small Cu nanoparticles through a strong interaction between CeO_(2)and Cu,leading to the formation of more Cu+–ZnO x interfacial sites.However,higher CeO_(2)contents resulted in the formation of larger Cu nanoparticles and an excess of Cu+–CeO x interfacial sites.Consequently,the Cu/5CeO_(2)/ZnO catalyst with maximal Cu–ZnO interfaces exhibited the highest H 2 production rate of 94.6 mmolH2/(gcat·h),which was 1.5 and 10.2 times higher than those of Cu/ZnO and Cu/CeO_(2),respectively.
基金supported by the Key Technologies R&D Program of China(2021YFA1502804)the Strategic Priority Research Program of the Chinese Academy of Science(XDB0450102)+2 种基金the National Natural Science Foundation of China(22172150,22222306,22221003,and 22432004)the Innovation Program for Quantum Science and Technology(2021ZD0303302)the high-performance computational resources provided by the University of Science and Technology of China and Hefei Advanced Computing Center。
文摘The reverse water−gas shift(RWGS)reaction is a key process for CO_(2) conversion and sustainable fuel production,yet the nature of the active sites on Pt/TiO_(2) cluster catalysts remains elusive.Using first-principles microkinetic simulations,we systematically investigated the catalytic behavior of Pt clusters on TiO_(2) under operational reaction conditions.We studied three distinct catalytic sites-Pt cluster surfaces,oxygen vacancies(O_(V))on TiO_(2),and Pt−O_(V)−Ti interfaces-and revealed that the Pt−O_(V)−Ti interface exhibited the highest RWGS activity via a redox mechanism.This synergy enhances CO_(2) activation and facilitates oxygen reduction more effectively than the isolated O_(V) on TiO_(2),which show 4-fold lower activity.In contrast,CO-covered Pt clusters show minimal CO_(2) activation but serve as H2 dissociation sites,enabling hydrogen spillover to adjacent O_(V) on TiO_(2),thereby sustaining the RWGS process.Kinetic analysis revealed OH reduction to H2O as the rate-determining step on both interfacial Pt−O_(V)−Ti and at the O_(V) on the TiO_(2)−X support.These findings highlight the pivotal role of the Pt−O_(V)−Ti interface in driving the RWGS and offer a design strategy for optimizing high-temperature CO_(2) hydrogenation catalysts by maximizing the number of interfacial active sites.
基金support from the National Natural Science Foundation of China(Nos.22221003 and 22071225)the Plan for Anhui Major Provincial Science&Technology Project(Nos.202203a0520013 and 2021d05050006)the fellowship of China Postdoctoral Science Foundation(No.2022M712179).
文摘Metal oxide supported metal catalysts show promising catalytic performance in many industry-relevant reactions.However,the enhancement of performance is often limited by the insufficient metal/metal oxide interface.In this work,we demonstrate a general synthesis of Pt-early transition metal oxide(Pt-MO_(x),M=Ti,Zr,V,and Y)catalysts with rich interfacial sites,which is based on the air-induced surface segregation and oxidation of M in the supported Pt-M alloy catalysts.Systematic characterizations verify the dynamic structural response of Pt-M alloy catalysts to air and the formation of Pt-MO_(x) catalysts with abundant interfacial sites.The prepared Pt-TiO_(x) interfacial catalysts exhibit improved performance in hydrogenation reactions of benzaldehyde,nitrobenzene,styrene,and furfural,as a result of the heterolytic dissociation of H_(2) at Pt-metal oxide interfacial sites.
基金supported by the National Key R&D Program of China (2016YFB0600901)the National Natural Science Foundation of China (21525626, 21603159, 21676181)the Program of Introducing Talents of Discipline to Universities (B06006)
文摘Metal oxide-promoted Rh-based catalysts have been widely used for CO2hydrogenation,especially for the ethanol synthesis.However,this reaction usually suffers low CO2conversion and alcohols selectivity due to the formation of byproducts methane and CO.This paper describes an efficient vanadium oxide promoted Rh-based catalysts confined in mesopore MCM-41.The Rh-0.3VOx/MCM-41 catalyst shows superior conversion(~12%)and ethanol selectivity(~24%)for CO2hydrogenation.The promoting effect can be attributed to the synergism of high Rh dispersion by the confinement effect of MCM-41 and the formation of VOx-Rh interface sites.Experimental and theoretical results indicate the formation of til-CO at VOx-Rh interface sites is easily dissociated into*CHx,and then*CHxcan be inserted by CO to form CH3CO*,followed by CH3CO*hydrogenation to ethanol.
基金The authors would like to thank the financial support from the Ministry of Business,Innovation&Employment in New Zealand under the MBIE Endeavour"Smart Ideas"grant(UOCX1905).
文摘One-dimensional titanium dioxide nanorod(TNR)-supported Cu catalysts(2.5 wt.%-12.5 wt.%)were synthesized using deposition-precipitation.X-ray photoelectron spectroscopy,temperature programmed reduction and CO chemisorption measurements showed that Cu doping over TNR offered metal-support interactions and interfacial active sites that had a profound impact on the catalytic performance.The role of the Cu-TNR interface was investigated by comparing the catalytic activity of Cu-TNR catalysts with that of pure CuO nanoparticles in CO oxidation.The presence of highly dispersed copper species,a high number of interfacial active sites,CO adsorption capacity and surface/lattice oxygen were found to be responsible for the excellent activity of 7.5CU-TNR(ie,Cu loading of 7.5 wt.%on TNR).Moreover,the Cu-TNR catalysts followed the Langmuir-Hinshelwood reaction mechanism with 7.5CU-TNR,exhibiting an apparent activation energy of 44.7 kJ/mol.The TNR-supported Cu catalyst gave the highest interfacial catalytic activity in medium-temperature CO oxidation(120-240℃)compared to other commonly used supports,including titanium dioxide nanoparticles(TiO2-P25),silica(SiO2)and alumina(Al20g)in which copper species were nonhomogeneously dispersed.This study confirms that medium-temperature CO oxidation is highly sensitive to the morphology and structure of the supporting material.
基金National Key Research and Development Program of China(2022YFE0135000)National Natural Science Foundation of China(42175123、42107125)Fundamental Research Funds for the Central Universities,Nankai University(63231205).
文摘The strong metal-support interaction(SMSI)in supported catalysts plays a dominant role in catalytic degradation,upgrading,and remanufacturing of environmental pollutants.Previous studies have shown that SMSI is crucial in supported catalysts'activity and stability.However,for redox reactions catalyzed in environmental catalysis,the enhancement mechanism of SMSI-induced oxygen vacancy and electron transfer needs to be clarified.Additionally,the precise control of SMSI interface sites remains to be fully understood.Here we provide a systematic review of SMSI's catalytic mechanisms and control strategies in purifying gaseous pollutants,treating organic wastewater,and valorizing biomass solid waste.We explore the adsorption and activation mechanisms of SMSI in redox reactions by examining interfacial electron transfer,interfacial oxygen vacancy,and interfacial acidic sites.Furthermore,we develop a precise regulation strategy of SMSI from systematical perspectives of interface effect,crystal facet effect,size effect,vip ion doping,and modification effect.Importantly,we point out the drawbacks and breakthrough directions for SMSI regulation in environmental catalysis,including partial encapsulation strategy,size optimization strategy,interface oxygen vacancy strategy,and multi-component strategy.This review article provides the potential applications of SMSI and offers guidance for its controlled regulation in environmental catalysis.