The nitrogen-coordinated metal single-atom catalysts(M−N−C SACs)with an ultra-high metal loading synthetized by direct high-temperature pyrolysis have been widely reported.However,most of metal single atoms in these c...The nitrogen-coordinated metal single-atom catalysts(M−N−C SACs)with an ultra-high metal loading synthetized by direct high-temperature pyrolysis have been widely reported.However,most of metal single atoms in these catalysts were buried in the carbon matrix,resulting in a low metal utilization and inaccessibility for adsorption of reactants during the catalytic process.Herein,we reported a facile synthesis based on the hard-soft acid-base(HSAB)theory to fabricate Co single-atom catalysts with highly exposed metal atoms ligated to the external pyridinic-N sites of a nitrogen-doped carbon support.Benefiting from the highly accessible Co active sites,the prepared Co−N−C SAC exhibited a superior oxygen reduction reactivity comparable to that of the commercial Pt/C catalyst,showing a high turnover frequency(TOF)of 0.93 e^(−)·s^(-1)·site^(-1)at 0.85 V vs.RHE,far exceeding those of some representative SACs with a ultra-high metal content.This work provides a rational strategy to design and prepare M−N−C single-atom catalysts featured with high site-accessibility and site-density.展开更多
By simplifying catalyst-product separation and reducing phosphorus waste,heterogeneous hydroformylation offers a more sustainable alternative to homogeneous processes.However,heterogeneous hydroformylation catalysts d...By simplifying catalyst-product separation and reducing phosphorus waste,heterogeneous hydroformylation offers a more sustainable alternative to homogeneous processes.However,heterogeneous hydroformylation catalysts developed thus far still suffer from the issues of much lower activity and metal leaching,which severely hinder their practical application.Here,we demonstrate that incorporating phosphorus(P)atoms into graphitic carbon nitride(PCN)supports facilitates charge transfer from Rh to the PCN support,thus largely enhancing electronic metal-support interactions(EMSIs).In the styrene hydroformylation reaction,the activity of Rh_(1)/PCN single-atom catalysts(SACs)with varying P contents exhibited a volcano-shaped relationship with P doping,where the Rh_(1)/PCN SAC with optimal P doping showed exceptional activity,approximately 5.8-and 3.3-fold greater than that of the Rh_(1)/g-C_(3)N_(4)SAC without P doping and the industrial homogeneous catalyst HRh(CO)(PPh_(3))_(3),respectively.In addition,the optimal Rh_(1)/PCN SAC catalyst also demonstrated largely enhanced multicycle stability without any visible metal aggregation owing to the increased EMSIs,which sharply differed from the severe metal aggregation of large nanoparticles on the Rh_(1)/g-C_(3)N_(4)SAC.Mechan-istic studies revealed that the enhanced catalytic performance could be attributed to electron-deficient Rh species,which reduced CO adsorption while simultaneously promoting alkene adsorption through increased EMSIs.These findings suggest that tuning EMSIs is an effective way to achieve SACs with high activity and durability.展开更多
The co-production of hydrogen and value-added biochemicals from lignocellulose utilizing solar energy has been regarded as one of the technologies most potentially able to alleviate the current energy crisis.Here,we d...The co-production of hydrogen and value-added biochemicals from lignocellulose utilizing solar energy has been regarded as one of the technologies most potentially able to alleviate the current energy crisis.Here,we demonstrate a cost-effective photoreforming strategy for lignocellulose valorization using a carbon nitride-supported platinum single-atom photocatalyst.An advanced H_(2) evolution rate of 6.34 mmol molPt^(-1) h^(-1) is achieved over the optimal catalyst,which is around 4.6 and 30.5 times higher compared with the nanosized Pt counterpart and pristine carbon nitride,respectively.Meanwhile,the monosaccharides are oxidized to value-added lactic acid with>99%conversion and extraordinary selectivity up to 97%.The theoretical calculations show that with Pt incorporation,the photogenerated holes are predominantly localized on the metal sites while the photogenerated electrons are concentrated on C_(3)N_(4),thus enhancing the effective separation of charge carriers.This work provides a promising avenue for the simultaneous production of green H2 and bio-based chemicals by biomass photorefinery.展开更多
The single-atom M-N-C(M typically being Co or Fe)is a prominent material with exceptional reactivity in areas of catalysis for sustainable energy.However,the formation of metal nanoparticles in M-N-C materials is coup...The single-atom M-N-C(M typically being Co or Fe)is a prominent material with exceptional reactivity in areas of catalysis for sustainable energy.However,the formation of metal nanoparticles in M-N-C materials is coupled with hightemperature calcination conditions,limiting the density of M-Nx active sites and thus restricting the catalytic performance of such catalysts.Herein,we describe an effective decoupling strategy to construct high-density M-Nx active sites by generating polyfurfuryl alcohol in the MOF precursor,effectively preventing the formation of metal nanoparticles even with up to 6.377%cobalt loading.This catalyst showed a high H_(2) production rate of 778mLgcat^(−1) h^(−1) when used in the dehydrogenation reaction of formic acid.In addition to the high density of the active site,a curved carbon surface in the structure is also thought to be the reason for the high performance of the catalyst.展开更多
Enhancing the corrosion resistance of carriers within Fenton-like systems and inhibiting the migration and aggregation of single atoms in reaction environments are essential for maintaining both high activity and stab...Enhancing the corrosion resistance of carriers within Fenton-like systems and inhibiting the migration and aggregation of single atoms in reaction environments are essential for maintaining both high activity and stability at catalytic sites,thus meeting fundamental requirements for practical application.The Fenton-like process of activating various strong oxidants by silicon-based single atom catalysts(SACs)prepared based on silicon-based materials(mesoporous silica,silicon-based minerals,and organosilicon materials)has unique advantages such as structural stability(especially important under strong oxidation conditions)and environmental protection.In this paper,the preparation strategies for the silicon-based SACs were assessed first,and the structural characteristics of various silicon-based SACs are systematically discussed,their application process and mechanism in Fenton-like process to achieve water purification are investigated,and the progress of Fenton-like process in density functional theory(DFT)of siliconbased derived single atom catalysts is summarized.In this paper,the preparation strategies and applications of silicon-based derived SACs are analyzed in depth,and their oxidation activities and pathways to different pollutants in water are reviewed.In addition,this paper also summarizes the device design and application of silicon-based derived SACs,and prospects the future development of silicon-based SACs in Fenton-like applications.展开更多
Metal-nitrogen-carbon(M-N-C)single-atom catalysts are widely utilized in various energy-related catalytic processes,offering a highly efficient and cost-effective catalytic system with significant potential.Recently,c...Metal-nitrogen-carbon(M-N-C)single-atom catalysts are widely utilized in various energy-related catalytic processes,offering a highly efficient and cost-effective catalytic system with significant potential.Recently,curvature-induced strain has been extensively demonstrated as a powerful tool for modulating the catalytic performance of M-N-C catalysts.However,identifying optimal strain patterns using density functional theory(DFT)is computationally intractable due to the high-dimensional search space.Here,we developed a graph neural network(GNN)integrated with an advanced topological data analysis tool-persistent homology-to predict the adsorption energy response of adsorbate under proposed curvature patterns,using nitric oxide electroreduction(NORR)as an example.Our machine learning model achieves high accuracy in predicting the adsorption energy response to curvature,with a mean absolute error(MAE)of 0.126 eV.Furthermore,we elucidate general trends in curvature-modulated adsorption energies of intermediates across various metals and coordination environments.We recommend several promising catalysts for NORR that exhibit significant potential for performance optimization via curvature modulation.This methodology can be readily extended to describe other non-bonded interactions,such as lattice strain and surface stress,providing a versatile approach for advanced catalyst design.展开更多
Lithium-sulfur batteries(LSBs)have become a favorable contender for next-generation electrochemical energy storage systems due to their outstanding features such as high energy density,low cost,and environmental frien...Lithium-sulfur batteries(LSBs)have become a favorable contender for next-generation electrochemical energy storage systems due to their outstanding features such as high energy density,low cost,and environmental friendliness.However,the commercialization of LSBs is still characterized by critical issues such as low sulfur utilization,short cycle life,and poor rate performance,which need to be resolved.Single-atom catalysts,with their outstanding features such as ultra-high atom utilization rate close to 100%and adjustable coordination configuration,have received extensive attention in the field of lithium-sulfur battery research.In this paper,the preparation and characterization of single-atom catalysts for Li-S batteries are briefly introduced,and the latest research progress of single-atom catalysts for Li-S batteries is reviewed from three aspects:cathode,separator and anode.Finally,the key technical problems and future research directions of single-atom catalysts for lithium-sulfur batteries are also prospected,with a view to promoting the further development of commercialized LSBs.展开更多
Single-atom catalysts(SACs),as the rising stars in the field of catalytic science,are leading catalytic technology into an un-precedented new era.However,the synthe-sis of high-performance SACs with well-de-fined acti...Single-atom catalysts(SACs),as the rising stars in the field of catalytic science,are leading catalytic technology into an un-precedented new era.However,the synthe-sis of high-performance SACs with well-de-fined active sites and high loadings under precise control has become a hotly debated topic in scientific research.Metal-organic frameworks(MOFs),with their exceptional properties such as ultrahigh specific surface areas,precisely controllable structural de-signs,and highly flexible functional cus-tomization capabilities,are regarded as one of the ideal matrices for supporting and sta-bilizing SACs.This review provides an in-sightful overview of the diverse preparation strategies for MOFs-derived SACs.It comprehen-sively analyzes the unique advantages and challenges of each method in achieving efficient synthesis of SACs,emphasizing the crucial role of optimized processes in unlocking the antici-pated performance of SACs.Furthermore,this review delves into a series of advanced charac-terization techniques,including aberration-corrected scanning transmission electron mi-croscopy(AC-STEM),electron energy loss spectroscopy(EELS),X-ray absorption spec-troscopy(XAS),and infrared absorption spectroscopy(IRAS),offering valuable insights into the atomic-scale fine structures and properties of SACs,significantly advancing the under-standing of SAC mechanisms.Moreover,this review focuses on exploring the potential appli-cations of MOFs-derived SACs in electrocatalysis frontier fields.This comprehensive exami-nation lays a solid theoretical foundation and provides a directional guidance for the rational design and controllable synthesis of high-performance MOFs-derived SACs.展开更多
Metal-sulfur electrochemistry represents a promising energy storage technology due to the natural abundance and unparalleled theoretical specific capacity of 1675 mAh g^(-1)of sulfur based on two-electron redox reacti...Metal-sulfur electrochemistry represents a promising energy storage technology due to the natural abundance and unparalleled theoretical specific capacity of 1675 mAh g^(-1)of sulfur based on two-electron redox reaction(S^(0)■S^(2-)).Commercially viable metal-sulfur batteries(MSBs)are hindered by sluggish sulfur conversion kinetics,which reduce the utilization efficiency of sulfur and lead to polysulfide shuttling.Single-atom catalysts(SACs)exhibit specific catalytic activity,a high atomic utilization ratio,and flexible selectivity,and are considered exceptional electrocatalysts for addressing the intractable challenges encountered by the MSBs.This review summarizes the recent progress in SACs for boosting the sulfur electrochemistry in MSBs,focusing on sulfur host materials,modified separators and functional interlayers,and analyzes the in-depth mechanisms of SACs.Moreover,the correlation between the coordination environments and the intrinsic activity of SACs is discussed.Finally,the main challenges and potential research directions of SACs for high-energy-density and long-life MSBs are outlined.This study provides significant guidance for constructing novel SACs that can accelerate the sulfur conversion kinetics in MSBs.展开更多
Single-atom catalysts(SACs)have garnered interest in designing their ligand environments,facilitating the modification of single catalytic sites toward high activity and selectivity.Despite various synthetic approache...Single-atom catalysts(SACs)have garnered interest in designing their ligand environments,facilitating the modification of single catalytic sites toward high activity and selectivity.Despite various synthetic approaches,it remains challenging to achieve a catalytically favorable coordination structure simultaneously with the feasible formation of SACs at low temperatures.Here,a new type of coordination structure for Pt SACs is introduced to offer a highly efficient hydrogen evolution reaction(HER)catalyst,where Pt SACs are readily fabricated by atomically confining PtCl_(2)on chemically driven NO_(2)sites in two-dimensional nitrogen-doped carbon nanosheets at room temperature.The resultant Pt SACs form the NO_(2)-Pt-Cl_(2)coordination structure with an atomic dispersion,as revealed by X-ray spectroscopy and transmission electron microscopy investigations.Moreover,our first-principles density functional theory(DFT)calculations show strong interactions in the coordination by computing the binding energy and charge density difference between PtCl_(2)and NO_(2).Pt SACs,established on the NO_(2)-functionalized carbon support,demonstrate the onset potential of 25 mV,Tafel slope of 40 mV dec^(-1),and high specific activity of 1.35 A mgPt^(-1).Importantly,the Pt SACs also exhibit long-term stability up to 110 h,which is a significant advance in the field of single-atom Pt catalysts.The newly developed coordination structure of Pt SACs features a single Pt active center,providing hydrogen binding ability comparable to that of Pt(111),enhanced long-term durability due to strong metal-support interactions,and the advantage of room-temperature fabrication.展开更多
Metal oxides as support for constructing precious metal single-atom catalysts hold great promise for a wide range of industrial applications,but achieving a high-loading of thermally stable metal single atoms on such ...Metal oxides as support for constructing precious metal single-atom catalysts hold great promise for a wide range of industrial applications,but achieving a high-loading of thermally stable metal single atoms on such supports has been challenging.Herein,we report an innovative strategy for the fabrication of high-density single-atoms(Rh,Ru,Pd)catalysts on CaAl-layered double hydroxides(CaAl-LDH)via isomorphous substitution.The Rh species have occupied Ca^(2+)vacancies within CaAl-LDH laminate by ion-exchange,facilitating a substantial loading of isolated Rh single-atoms.Such catalysts displayed superior performance in the selective hydrogenation to quinoline,pivotal for liquid organic hydrogen storage,and the universality for the hydrogenation of N-heterocyclic aromatic hydrocarbons was also verified.Combining the experimental results and density functional theory calculations,the pathway of quinoline hydrogenation over Rh1CaAl-LDH was proposed.This synthetic strategy marks a significant advancement in the field of single-atom catalysts,expanding their horizons in green chemical processes.展开更多
Single-atom catalysts(SACs)offer a promising approach for maximizing noble metals utilization in catalytic processes.However,their performance in CO_(2)hydrogenation is often constrained by the nature of metal-support...Single-atom catalysts(SACs)offer a promising approach for maximizing noble metals utilization in catalytic processes.However,their performance in CO_(2)hydrogenation is often constrained by the nature of metal-support interactions.In this study,we synthesized TiO_(2)supported Pt SACs(Pt1/TiO_(2)),with Pt single atoms dispersed on rutile(Pt1/R)and anatase(Pt1/A)phases of TiO_(2)for the reverse water-gas shift(RWGS)reaction.While both catalysts maintained 100%CO selectivity over time,Pt1/A achieved a CO_(2)conversion of 7.5%,significantly outperforming Pt1/R(3.6%).In situ diffuse reflectance infrared Fourier-transform spectroscopy and X-ray photoelectron spectroscopy revealed distinct reaction pathways:the COOH pathway was dominant on Pt1/A,whereas the–OH+HCO pathway was more competitive on Pt1/R.Analysis of electron metal-support interactions and energy barrier calculations indicated that Pt1/A better stabilized metallic Pt species and facilitates more favorable reaction pathways with lower energy barriers.These findings provide valuable insights for the design of more efficient SAC systems in CO_(2)hydrogenation processes.展开更多
Hydrogen is a highly promising energy carrier because of its renewable and clean qualities.Among the different methods for H_(2) production,photoelectrocatalysis(PEC)water splitting has garnered significant interest,t...Hydrogen is a highly promising energy carrier because of its renewable and clean qualities.Among the different methods for H_(2) production,photoelectrocatalysis(PEC)water splitting has garnered significant interest,thanks to the abundant and perennial solar energy.Single-atom catalysts(SACs),which feature well-distributed atoms anchored on supports,have gained great attention in PEC water splitting for their unique advantages in overcoming the limitations of conventional PEC reactions.Herein,we comprehensively review SAC-incorporated photoelectrocatalysts for efficient PEC water splitting.We begin by highlighting the benefits of SACs in improving charge transfer,catalytic selectivity,and catalytic activity,which address the limitations of conventional PEC reactions.Next,we provide a comprehensive overview of established synthetic techniques for optimizing the properties of SACs,along with modern characterization methods to confirm their unique structures.Finally,we discuss the challenges and future directions in basic research and advancements,providing insights and guidance for this developing field.展开更多
The Ni single-atom catalyst dispersed on nitrogen doped graphene support has attracted much interest due to the high selectivity in electro-catalyzing CO_(2)reduction to CO,yet the chemical inertness of the metal cent...The Ni single-atom catalyst dispersed on nitrogen doped graphene support has attracted much interest due to the high selectivity in electro-catalyzing CO_(2)reduction to CO,yet the chemical inertness of the metal center renders it to exhibit electrochemical activity only under high overpotentials.Herein,we report P-and S-doped Ni single-atom catalysts,i.e.symmetric Ni_(1)/PN_(4)and asymmetric Ni1/SN_(3)C can exhibit high catalytic activity of CO_(2)reduction with stable potential windows.It is revealed that the key intermediate*COOH in CO_(2)electroreduction is stabilized by heteroatom doping,which stems from the upward shift of the axial d_(z2)orbital of the active metal Ni atom.Furthermore,we investigate the potential-dependent free energetics and dynamic properties at the electrochemical interface on the Ni1/SN3C catalyst using ab initio molecular dynamics simulations with a full explicit solvent model.Based on the potential-dependent microkinetic model,we predict that S-atom doped Ni SAC shifts the onset potential of CO_(2)electroreduction from–0.88 to–0.80 V vs.RHE,exhibiting better activity.Overall,this work provides an in-depth understanding of structure-activity relationships and atomic-level electrochemical interfaces of catalytic systems,and offers insights into the rational design of heteroatom-doped catalysts for targeted catalysis.展开更多
The reduction of N2 to NH_(3) is an important reaction for the industrial production of ammonia gas.Here,we theoretically study the thermal synthesis of ammonia catalyzed by Ru1@Mo_(2)CO_(x)single-atom catalyst(SAC),w...The reduction of N2 to NH_(3) is an important reaction for the industrial production of ammonia gas.Here,we theoretically study the thermal synthesis of ammonia catalyzed by Ru1@Mo_(2)CO_(x)single-atom catalyst(SAC),where Ru atoms are anchored on the oxygen vacancy of the defective Mo2COx.The results show that Ru1@Mo_(2)CO_(x)exhibits excellent stability,and can effectively adsorb and activate N2,owing to up to0.87|e|charge transfer from it to N2.The optimal pathway of N2-to-NH_(3) conversion is association pathway I,of which the rate-determining step is*NH_(2)→*NH_(3) with the barrier energy of 1.26 eV.Especially,the Mo_(2)CO_(x)center functions as an electron reservoir,donating electrons to the NxHy species,while the Ru single atom serves as a charge transfer pathway,thereby enhancing the reaction activity.This finding provides a theoretical foundation for the rational design of MXene-based SACs for thermal catalytic NH_(3) synthesis.展开更多
In the field of catalytic hydro-genation,two primary mecha-nistic pathways,namely the Ho-riuti-Polanyi(HP)mechanism and the non-HP mechanism,have been extensively investi-gated.Current understandings suggested that th...In the field of catalytic hydro-genation,two primary mecha-nistic pathways,namely the Ho-riuti-Polanyi(HP)mechanism and the non-HP mechanism,have been extensively investi-gated.Current understandings suggested that the non-HP mechanism preferred to occur on the coinage metal surfaces,such as copper,silver,and gold,which exhibited low activity towards H_(2) dissociation.Herein,we offered a detailed theoretical investigation into the mechanisms of CO_(2)hydrogenation to formic acid on M_(1)-In_(2)O_(3)(111)surfaces,using density functional theory calculations.Our calculations provided novel in-sights into the preference of the non-HP mechanism on reduced single-atom noble metal cata-lysts,such as r-Rh_(1)-In_(2)O_(3)(111)and r-Ir_(1)-In_(2)O_(3)(111).In these cases,molecularly adsorbed H_(2) would be polarized into H^(δ−)-H^(δ+),thus facilitating the electrophilic attack to the O in CO_(2).Conversely,the H^(δ+)species,derived from heterolytically dissociated H_(2),exhibited a strong affinity on the adjacent oxygen site at the M-O-In interface.This strong adsorption resulted in a higher energy barrier for CO_(2)hydrogenation,thereby rendering the HP mechanism less viable than the non-HP one.Our results were anticipated to provide a deeper understanding of hydrogenation reactions on oxide-supported noble single-atom catalysts and theoretical guidance for the development of novel high-performance catalysts for catalytic hydrogena-tion reactions.展开更多
Lithium-sulfur(Li-S)batteries are regarded as the most formidable competitor to lithium-ion batteries due to their superior theoretical capacity.However,the negative impact of soluble lithium polysulfide(LiPSs)and slo...Lithium-sulfur(Li-S)batteries are regarded as the most formidable competitor to lithium-ion batteries due to their superior theoretical capacity.However,the negative impact of soluble lithium polysulfide(LiPSs)and slow redox reaction kinetics seriously hamper the commercialization of Li-S batteries.In this study,a defect-rich single-atom catalyst with an oversaturated asymmetric Fe-N_(5)coordination structure anchored in defective g-C_(3)N_(4)(C_(3)N_(4)-Fe@rGO)is designed via an absorption-pyrolysis strategy.The two-dimensional(2D)conducting C_(3)N_(4)@graphene structure with abundant defect sites accelerates the trans-fer and transportation of lithium ions and electrons.The oversaturated asymmetric Fe-N_(5)coordination structure effectively improves the adsorbility of LiPSs and accelerates the redox kinetics of sulfur species.Hence,the Li-S cell with a C_(3)N_(4)-Fe@rGO modified separator reveals a high initial capacity(1197.1 mAh g^(-1) at 0.2 C)and a low capacity decay rate(0.037%per cycle after 900 cycles at 1 C).Even at high sulfur loading and extreme temperatures of 0℃,it also shows good cycling performance.This work creates ideas for synthesizing oversaturated single-atom coordination environments and an efficient route to the practical realization of the Li-S batteries.展开更多
Metallic single-atom catalysts(SACs)have demonstrated high activity and potential in enhancing the hydrogen storage properties of MgH_(2).However,previous reports primarily focus on supported SACs,which often suffer f...Metallic single-atom catalysts(SACs)have demonstrated high activity and potential in enhancing the hydrogen storage properties of MgH_(2).However,previous reports primarily focus on supported SACs,which often suffer from insufficient co ntact between single-atom active sites and hydrogen storage materials.In this study,the precursor Mo(CO)_(6)is uniformly dispersed on the surface of MgH_(2)via impregnation adsorption,leading to the formation of alloy-type Mo single atoms after hydrogenation/dehydrogenation activation.This alloy structure enables zero-distance contact between catalytic sites and the hydrogen storage material,facilitating electron exchange and hydrogen transfer between the Mo sites and MgH_(2).The MgH_(2)loaded with Mo single atoms(Mo_(1)-MgH_(2))exhibits excellent hydrogen absorption and desorption properties,with the initial hydrogen release temperature lowered from 323 to 218℃.At 250℃,Mo_(1)-MgH_(2)absorbs over 6.77 wt% of hydrogen within 1 min and releases over 5.85 wt% within 4 h.During 10 cycles of hydrogenation and dehydrogenation reactions,Mo_(1)-MgH_(2)maintains nearly 100% capacity and shows stable kinetics.This work provides new insights into the design and fabrication of catalysts for hydrogen storage materials.展开更多
Hydroisomerization of n-alkanes plays an important role in fuel and lubricants processing.Bifunctional catalysts with ultralow platinum loading have recently been reported successively for hydroisomerisation.Herein,th...Hydroisomerization of n-alkanes plays an important role in fuel and lubricants processing.Bifunctional catalysts with ultralow platinum loading have recently been reported successively for hydroisomerisation.Herein,the catalysts were prepared successfully with different methods to improve the catalytic performance.The conversion of 0.01%Pt1@CeOx/SAPO-11 prepared by co-calcination method(0.01%Pt1@CS-c)is 71.4%,25%higher than the other prepared by precipitation method.The turnover frequency per active surface platinum site(TOFPt)of 0.01%Ptl@CS-c is as high as 13115 h^(-1).Revealed by the X-ray photoelectron spectroscopy(XPS)results,the quality of phase boundary/intersurface between ceria and zeolite is found significantly different.The conjunction quality of phase boundary directly affects the spillover rate of intermediate species,which further leads to an apparent activity difference.In addition,the possible role of ceria in the reaction is discussed,rather than just as a carrier for the active metal atoms.展开更多
Electrocatalytic reduction of carbon dioxide(CO_(2))to carbon monoxide(CO)is an effective strategy to achieve carbon neutrality.High selective and low-cost catalysts for the electrocatalytic reduction of CO_(2)have re...Electrocatalytic reduction of carbon dioxide(CO_(2))to carbon monoxide(CO)is an effective strategy to achieve carbon neutrality.High selective and low-cost catalysts for the electrocatalytic reduction of CO_(2)have received increasing attention.In contrast to the conventional tube furnace method,the high-temperature shock(HTS)method enables ultra-fast thermal processing,superior atomic efficiency,and a streamlined synthesis protocol,offering a simplified method for the preparation of high-performance single-atom catalysts(SACs).The reports have shown that nickel-based SACs can be synthesized quickly and conveniently using the HTS method,making their application in CO_(2)reduction reactions(CO_(2)RR)a viable and promising avenue for further exploration.In this study,the effect of heating temperature,metal loading and different nitrogen(N)sources on the catalyst morphology,coordination environment and electrocatalytic performance were investigated.Under optimal conditions,0.05Ni-DCD-C-1050 showed excellent performance in reducing CO_(2)to CO,with CO selectivity close to 100%(−0.7 to−1.0 V vs RHE)and current density as high as 130 mA/cm^(2)(−1.1 V vs RHE)in a flow cell under alkaline environment.展开更多
基金supported by Shanxi Province Science Foundation for Youths(202203021212300)Taiyuan University of Science and Technology Scientific Research Initial Funding(20212064)Outstanding Doctoral Award Fund in Shanxi Province(20222060).
文摘The nitrogen-coordinated metal single-atom catalysts(M−N−C SACs)with an ultra-high metal loading synthetized by direct high-temperature pyrolysis have been widely reported.However,most of metal single atoms in these catalysts were buried in the carbon matrix,resulting in a low metal utilization and inaccessibility for adsorption of reactants during the catalytic process.Herein,we reported a facile synthesis based on the hard-soft acid-base(HSAB)theory to fabricate Co single-atom catalysts with highly exposed metal atoms ligated to the external pyridinic-N sites of a nitrogen-doped carbon support.Benefiting from the highly accessible Co active sites,the prepared Co−N−C SAC exhibited a superior oxygen reduction reactivity comparable to that of the commercial Pt/C catalyst,showing a high turnover frequency(TOF)of 0.93 e^(−)·s^(-1)·site^(-1)at 0.85 V vs.RHE,far exceeding those of some representative SACs with a ultra-high metal content.This work provides a rational strategy to design and prepare M−N−C single-atom catalysts featured with high site-accessibility and site-density.
基金supported by the Petrochemical Research Institute Foundation(21-CB-09-01)the National Natural Science Foundation of China(22302186,22025205)+1 种基金the China Postdoctoral Science Foundation(2022M713030,2023T160618)the Fundamental Research Funds for the Central Universities(WK2060000058,WK2060000038).
文摘By simplifying catalyst-product separation and reducing phosphorus waste,heterogeneous hydroformylation offers a more sustainable alternative to homogeneous processes.However,heterogeneous hydroformylation catalysts developed thus far still suffer from the issues of much lower activity and metal leaching,which severely hinder their practical application.Here,we demonstrate that incorporating phosphorus(P)atoms into graphitic carbon nitride(PCN)supports facilitates charge transfer from Rh to the PCN support,thus largely enhancing electronic metal-support interactions(EMSIs).In the styrene hydroformylation reaction,the activity of Rh_(1)/PCN single-atom catalysts(SACs)with varying P contents exhibited a volcano-shaped relationship with P doping,where the Rh_(1)/PCN SAC with optimal P doping showed exceptional activity,approximately 5.8-and 3.3-fold greater than that of the Rh_(1)/g-C_(3)N_(4)SAC without P doping and the industrial homogeneous catalyst HRh(CO)(PPh_(3))_(3),respectively.In addition,the optimal Rh_(1)/PCN SAC catalyst also demonstrated largely enhanced multicycle stability without any visible metal aggregation owing to the increased EMSIs,which sharply differed from the severe metal aggregation of large nanoparticles on the Rh_(1)/g-C_(3)N_(4)SAC.Mechan-istic studies revealed that the enhanced catalytic performance could be attributed to electron-deficient Rh species,which reduced CO adsorption while simultaneously promoting alkene adsorption through increased EMSIs.These findings suggest that tuning EMSIs is an effective way to achieve SACs with high activity and durability.
文摘The co-production of hydrogen and value-added biochemicals from lignocellulose utilizing solar energy has been regarded as one of the technologies most potentially able to alleviate the current energy crisis.Here,we demonstrate a cost-effective photoreforming strategy for lignocellulose valorization using a carbon nitride-supported platinum single-atom photocatalyst.An advanced H_(2) evolution rate of 6.34 mmol molPt^(-1) h^(-1) is achieved over the optimal catalyst,which is around 4.6 and 30.5 times higher compared with the nanosized Pt counterpart and pristine carbon nitride,respectively.Meanwhile,the monosaccharides are oxidized to value-added lactic acid with>99%conversion and extraordinary selectivity up to 97%.The theoretical calculations show that with Pt incorporation,the photogenerated holes are predominantly localized on the metal sites while the photogenerated electrons are concentrated on C_(3)N_(4),thus enhancing the effective separation of charge carriers.This work provides a promising avenue for the simultaneous production of green H2 and bio-based chemicals by biomass photorefinery.
基金National Natural Science Foundation of China,Grant/Award Numbers:21603054,31671930Innovation and entrepreneurship training program for college students of Hebei Agricultural University,Grant/Award Numbers:2019085,s202010086046+2 种基金Scientific Research Development Fund project of Hebei Agricultural University,Grant/Award Number:JY2020028the Natural Science Foundation of Hebei Province,Grant/Award Numbers:B2016204131,B2016204136Young Topnotch Talents Foundation of Hebei Provincial Universities,Grant/Award Number:BJ2016027.
文摘The single-atom M-N-C(M typically being Co or Fe)is a prominent material with exceptional reactivity in areas of catalysis for sustainable energy.However,the formation of metal nanoparticles in M-N-C materials is coupled with hightemperature calcination conditions,limiting the density of M-Nx active sites and thus restricting the catalytic performance of such catalysts.Herein,we describe an effective decoupling strategy to construct high-density M-Nx active sites by generating polyfurfuryl alcohol in the MOF precursor,effectively preventing the formation of metal nanoparticles even with up to 6.377%cobalt loading.This catalyst showed a high H_(2) production rate of 778mLgcat^(−1) h^(−1) when used in the dehydrogenation reaction of formic acid.In addition to the high density of the active site,a curved carbon surface in the structure is also thought to be the reason for the high performance of the catalyst.
基金supported by National Natural Science Foundation of China(No.52170086)Natural Science Foundation of Shandong Province(No.ZR2021ME013)+1 种基金Natural science Foundation of Shaanxi province(No.2024JC-YBQN-0252)Special Scientific Research Project of Hanzhong City-Shaanxi University of Technology Co-construction State Key Laboratory(No.SXJ2106)。
文摘Enhancing the corrosion resistance of carriers within Fenton-like systems and inhibiting the migration and aggregation of single atoms in reaction environments are essential for maintaining both high activity and stability at catalytic sites,thus meeting fundamental requirements for practical application.The Fenton-like process of activating various strong oxidants by silicon-based single atom catalysts(SACs)prepared based on silicon-based materials(mesoporous silica,silicon-based minerals,and organosilicon materials)has unique advantages such as structural stability(especially important under strong oxidation conditions)and environmental protection.In this paper,the preparation strategies for the silicon-based SACs were assessed first,and the structural characteristics of various silicon-based SACs are systematically discussed,their application process and mechanism in Fenton-like process to achieve water purification are investigated,and the progress of Fenton-like process in density functional theory(DFT)of siliconbased derived single atom catalysts is summarized.In this paper,the preparation strategies and applications of silicon-based derived SACs are analyzed in depth,and their oxidation activities and pathways to different pollutants in water are reviewed.In addition,this paper also summarizes the device design and application of silicon-based derived SACs,and prospects the future development of silicon-based SACs in Fenton-like applications.
基金supported by the Natural Science Foundation of Xiamen,China(3502Z202472001)the National Natural Science Foundation of China(22402163,22021001,21925404,T2293692,and 22361132532)。
文摘Metal-nitrogen-carbon(M-N-C)single-atom catalysts are widely utilized in various energy-related catalytic processes,offering a highly efficient and cost-effective catalytic system with significant potential.Recently,curvature-induced strain has been extensively demonstrated as a powerful tool for modulating the catalytic performance of M-N-C catalysts.However,identifying optimal strain patterns using density functional theory(DFT)is computationally intractable due to the high-dimensional search space.Here,we developed a graph neural network(GNN)integrated with an advanced topological data analysis tool-persistent homology-to predict the adsorption energy response of adsorbate under proposed curvature patterns,using nitric oxide electroreduction(NORR)as an example.Our machine learning model achieves high accuracy in predicting the adsorption energy response to curvature,with a mean absolute error(MAE)of 0.126 eV.Furthermore,we elucidate general trends in curvature-modulated adsorption energies of intermediates across various metals and coordination environments.We recommend several promising catalysts for NORR that exhibit significant potential for performance optimization via curvature modulation.This methodology can be readily extended to describe other non-bonded interactions,such as lattice strain and surface stress,providing a versatile approach for advanced catalyst design.
基金supported by the Shenzhen Key Basic Research Project:Ionic Liquid-Assisted Synthesis of Single Catalyst and Its Applications in Lithium Sulfur Batteries(GXWD20220817125846003)Major Instrument Project of National Natural Science Foundation of China(62127807)Shenzhen Sustainable Development Special Project(KCXFZ20201221173000001).
文摘Lithium-sulfur batteries(LSBs)have become a favorable contender for next-generation electrochemical energy storage systems due to their outstanding features such as high energy density,low cost,and environmental friendliness.However,the commercialization of LSBs is still characterized by critical issues such as low sulfur utilization,short cycle life,and poor rate performance,which need to be resolved.Single-atom catalysts,with their outstanding features such as ultra-high atom utilization rate close to 100%and adjustable coordination configuration,have received extensive attention in the field of lithium-sulfur battery research.In this paper,the preparation and characterization of single-atom catalysts for Li-S batteries are briefly introduced,and the latest research progress of single-atom catalysts for Li-S batteries is reviewed from three aspects:cathode,separator and anode.Finally,the key technical problems and future research directions of single-atom catalysts for lithium-sulfur batteries are also prospected,with a view to promoting the further development of commercialized LSBs.
基金supported by Henan Province Key Research and Development and Promotion of Science and Technology Project(No.25A150001)the National Natural Science Foundation of China(Nos.22409171,22125303,92361302,and 92061203).
文摘Single-atom catalysts(SACs),as the rising stars in the field of catalytic science,are leading catalytic technology into an un-precedented new era.However,the synthe-sis of high-performance SACs with well-de-fined active sites and high loadings under precise control has become a hotly debated topic in scientific research.Metal-organic frameworks(MOFs),with their exceptional properties such as ultrahigh specific surface areas,precisely controllable structural de-signs,and highly flexible functional cus-tomization capabilities,are regarded as one of the ideal matrices for supporting and sta-bilizing SACs.This review provides an in-sightful overview of the diverse preparation strategies for MOFs-derived SACs.It comprehen-sively analyzes the unique advantages and challenges of each method in achieving efficient synthesis of SACs,emphasizing the crucial role of optimized processes in unlocking the antici-pated performance of SACs.Furthermore,this review delves into a series of advanced charac-terization techniques,including aberration-corrected scanning transmission electron mi-croscopy(AC-STEM),electron energy loss spectroscopy(EELS),X-ray absorption spec-troscopy(XAS),and infrared absorption spectroscopy(IRAS),offering valuable insights into the atomic-scale fine structures and properties of SACs,significantly advancing the under-standing of SAC mechanisms.Moreover,this review focuses on exploring the potential appli-cations of MOFs-derived SACs in electrocatalysis frontier fields.This comprehensive exami-nation lays a solid theoretical foundation and provides a directional guidance for the rational design and controllable synthesis of high-performance MOFs-derived SACs.
基金financial support from the National Natural Science Foundation of China(No.22379001 and 22309003)the Natural Science Research Project of Anhui Province Education department(No.2022AH030046)the Top Young Talents of Anhui University of Technology,the Young Scholars of the Introduction and Education of Talents in Anhui Province,and the Scientific Research Foundation of Anhui University of Technology for Talent Introduction。
文摘Metal-sulfur electrochemistry represents a promising energy storage technology due to the natural abundance and unparalleled theoretical specific capacity of 1675 mAh g^(-1)of sulfur based on two-electron redox reaction(S^(0)■S^(2-)).Commercially viable metal-sulfur batteries(MSBs)are hindered by sluggish sulfur conversion kinetics,which reduce the utilization efficiency of sulfur and lead to polysulfide shuttling.Single-atom catalysts(SACs)exhibit specific catalytic activity,a high atomic utilization ratio,and flexible selectivity,and are considered exceptional electrocatalysts for addressing the intractable challenges encountered by the MSBs.This review summarizes the recent progress in SACs for boosting the sulfur electrochemistry in MSBs,focusing on sulfur host materials,modified separators and functional interlayers,and analyzes the in-depth mechanisms of SACs.Moreover,the correlation between the coordination environments and the intrinsic activity of SACs is discussed.Finally,the main challenges and potential research directions of SACs for high-energy-density and long-life MSBs are outlined.This study provides significant guidance for constructing novel SACs that can accelerate the sulfur conversion kinetics in MSBs.
基金supported by the National Research Foundation of Korea(NRF)(NRF-2020M3H4A3106354,NRF-2021M3I3A1083946,and NRF-2021R1A6A3A01087461)the Korea Institute of Science and Technology,and the KISTI Supercomputing Center(KSC-2023-CRE-0492).
文摘Single-atom catalysts(SACs)have garnered interest in designing their ligand environments,facilitating the modification of single catalytic sites toward high activity and selectivity.Despite various synthetic approaches,it remains challenging to achieve a catalytically favorable coordination structure simultaneously with the feasible formation of SACs at low temperatures.Here,a new type of coordination structure for Pt SACs is introduced to offer a highly efficient hydrogen evolution reaction(HER)catalyst,where Pt SACs are readily fabricated by atomically confining PtCl_(2)on chemically driven NO_(2)sites in two-dimensional nitrogen-doped carbon nanosheets at room temperature.The resultant Pt SACs form the NO_(2)-Pt-Cl_(2)coordination structure with an atomic dispersion,as revealed by X-ray spectroscopy and transmission electron microscopy investigations.Moreover,our first-principles density functional theory(DFT)calculations show strong interactions in the coordination by computing the binding energy and charge density difference between PtCl_(2)and NO_(2).Pt SACs,established on the NO_(2)-functionalized carbon support,demonstrate the onset potential of 25 mV,Tafel slope of 40 mV dec^(-1),and high specific activity of 1.35 A mgPt^(-1).Importantly,the Pt SACs also exhibit long-term stability up to 110 h,which is a significant advance in the field of single-atom Pt catalysts.The newly developed coordination structure of Pt SACs features a single Pt active center,providing hydrogen binding ability comparable to that of Pt(111),enhanced long-term durability due to strong metal-support interactions,and the advantage of room-temperature fabrication.
文摘Metal oxides as support for constructing precious metal single-atom catalysts hold great promise for a wide range of industrial applications,but achieving a high-loading of thermally stable metal single atoms on such supports has been challenging.Herein,we report an innovative strategy for the fabrication of high-density single-atoms(Rh,Ru,Pd)catalysts on CaAl-layered double hydroxides(CaAl-LDH)via isomorphous substitution.The Rh species have occupied Ca^(2+)vacancies within CaAl-LDH laminate by ion-exchange,facilitating a substantial loading of isolated Rh single-atoms.Such catalysts displayed superior performance in the selective hydrogenation to quinoline,pivotal for liquid organic hydrogen storage,and the universality for the hydrogenation of N-heterocyclic aromatic hydrocarbons was also verified.Combining the experimental results and density functional theory calculations,the pathway of quinoline hydrogenation over Rh1CaAl-LDH was proposed.This synthetic strategy marks a significant advancement in the field of single-atom catalysts,expanding their horizons in green chemical processes.
文摘Single-atom catalysts(SACs)offer a promising approach for maximizing noble metals utilization in catalytic processes.However,their performance in CO_(2)hydrogenation is often constrained by the nature of metal-support interactions.In this study,we synthesized TiO_(2)supported Pt SACs(Pt1/TiO_(2)),with Pt single atoms dispersed on rutile(Pt1/R)and anatase(Pt1/A)phases of TiO_(2)for the reverse water-gas shift(RWGS)reaction.While both catalysts maintained 100%CO selectivity over time,Pt1/A achieved a CO_(2)conversion of 7.5%,significantly outperforming Pt1/R(3.6%).In situ diffuse reflectance infrared Fourier-transform spectroscopy and X-ray photoelectron spectroscopy revealed distinct reaction pathways:the COOH pathway was dominant on Pt1/A,whereas the–OH+HCO pathway was more competitive on Pt1/R.Analysis of electron metal-support interactions and energy barrier calculations indicated that Pt1/A better stabilized metallic Pt species and facilitates more favorable reaction pathways with lower energy barriers.These findings provide valuable insights for the design of more efficient SAC systems in CO_(2)hydrogenation processes.
基金supported by the National Natural Science Foundation of China(Nos.22209186,22479149)Self-deployed Projects of Ganjiang Innovation Academy,CAS(No.E355F006)+2 种基金Natural Science Foundation of Jiangxi Province(No.20242BAB23016)Key Research and Development Program of Jiangxi Province(Nos.20223BBG74004,20232BBG70003)Youth Innovation Promotion Association,Chinese Academy of Sciences(No.2023343).
文摘Hydrogen is a highly promising energy carrier because of its renewable and clean qualities.Among the different methods for H_(2) production,photoelectrocatalysis(PEC)water splitting has garnered significant interest,thanks to the abundant and perennial solar energy.Single-atom catalysts(SACs),which feature well-distributed atoms anchored on supports,have gained great attention in PEC water splitting for their unique advantages in overcoming the limitations of conventional PEC reactions.Herein,we comprehensively review SAC-incorporated photoelectrocatalysts for efficient PEC water splitting.We begin by highlighting the benefits of SACs in improving charge transfer,catalytic selectivity,and catalytic activity,which address the limitations of conventional PEC reactions.Next,we provide a comprehensive overview of established synthetic techniques for optimizing the properties of SACs,along with modern characterization methods to confirm their unique structures.Finally,we discuss the challenges and future directions in basic research and advancements,providing insights and guidance for this developing field.
文摘The Ni single-atom catalyst dispersed on nitrogen doped graphene support has attracted much interest due to the high selectivity in electro-catalyzing CO_(2)reduction to CO,yet the chemical inertness of the metal center renders it to exhibit electrochemical activity only under high overpotentials.Herein,we report P-and S-doped Ni single-atom catalysts,i.e.symmetric Ni_(1)/PN_(4)and asymmetric Ni1/SN_(3)C can exhibit high catalytic activity of CO_(2)reduction with stable potential windows.It is revealed that the key intermediate*COOH in CO_(2)electroreduction is stabilized by heteroatom doping,which stems from the upward shift of the axial d_(z2)orbital of the active metal Ni atom.Furthermore,we investigate the potential-dependent free energetics and dynamic properties at the electrochemical interface on the Ni1/SN3C catalyst using ab initio molecular dynamics simulations with a full explicit solvent model.Based on the potential-dependent microkinetic model,we predict that S-atom doped Ni SAC shifts the onset potential of CO_(2)electroreduction from–0.88 to–0.80 V vs.RHE,exhibiting better activity.Overall,this work provides an in-depth understanding of structure-activity relationships and atomic-level electrochemical interfaces of catalytic systems,and offers insights into the rational design of heteroatom-doped catalysts for targeted catalysis.
基金the financial support from National Natural Science Foundation of China(22479032,22363001 and 22250710677)the NSFC Center for Single-Atom Catalysis(22388102)+2 种基金the National Key R&D Project(2022YFA1503900)the Natural Science Special Foundation of Guizhou University(No.202140)Guizhou Provincial Key Laboratory Platform Project(ZSYS[2025]008).
文摘The reduction of N2 to NH_(3) is an important reaction for the industrial production of ammonia gas.Here,we theoretically study the thermal synthesis of ammonia catalyzed by Ru1@Mo_(2)CO_(x)single-atom catalyst(SAC),where Ru atoms are anchored on the oxygen vacancy of the defective Mo2COx.The results show that Ru1@Mo_(2)CO_(x)exhibits excellent stability,and can effectively adsorb and activate N2,owing to up to0.87|e|charge transfer from it to N2.The optimal pathway of N2-to-NH_(3) conversion is association pathway I,of which the rate-determining step is*NH_(2)→*NH_(3) with the barrier energy of 1.26 eV.Especially,the Mo_(2)CO_(x)center functions as an electron reservoir,donating electrons to the NxHy species,while the Ru single atom serves as a charge transfer pathway,thereby enhancing the reaction activity.This finding provides a theoretical foundation for the rational design of MXene-based SACs for thermal catalytic NH_(3) synthesis.
基金supported by the National Key Research and Development Program of Ministry of Sci-ence and Technology of China(No.2022YFA1504601)the National Natural Science Foundation of China(Nos.92045303,22132004,22121001,22072116,22072117,and 21773192).
文摘In the field of catalytic hydro-genation,two primary mecha-nistic pathways,namely the Ho-riuti-Polanyi(HP)mechanism and the non-HP mechanism,have been extensively investi-gated.Current understandings suggested that the non-HP mechanism preferred to occur on the coinage metal surfaces,such as copper,silver,and gold,which exhibited low activity towards H_(2) dissociation.Herein,we offered a detailed theoretical investigation into the mechanisms of CO_(2)hydrogenation to formic acid on M_(1)-In_(2)O_(3)(111)surfaces,using density functional theory calculations.Our calculations provided novel in-sights into the preference of the non-HP mechanism on reduced single-atom noble metal cata-lysts,such as r-Rh_(1)-In_(2)O_(3)(111)and r-Ir_(1)-In_(2)O_(3)(111).In these cases,molecularly adsorbed H_(2) would be polarized into H^(δ−)-H^(δ+),thus facilitating the electrophilic attack to the O in CO_(2).Conversely,the H^(δ+)species,derived from heterolytically dissociated H_(2),exhibited a strong affinity on the adjacent oxygen site at the M-O-In interface.This strong adsorption resulted in a higher energy barrier for CO_(2)hydrogenation,thereby rendering the HP mechanism less viable than the non-HP one.Our results were anticipated to provide a deeper understanding of hydrogenation reactions on oxide-supported noble single-atom catalysts and theoretical guidance for the development of novel high-performance catalysts for catalytic hydrogena-tion reactions.
基金supported by the National Natural Science Foundation of China(Nos.U21A2060 and 22178116)the Natural Science Foundation of Shanghai(No.22ZR1417400)the Fundamental Research Funds for the Central Universities(Nos.222201817001,50321041918013,JKA01221601,JKD01241701).
文摘Lithium-sulfur(Li-S)batteries are regarded as the most formidable competitor to lithium-ion batteries due to their superior theoretical capacity.However,the negative impact of soluble lithium polysulfide(LiPSs)and slow redox reaction kinetics seriously hamper the commercialization of Li-S batteries.In this study,a defect-rich single-atom catalyst with an oversaturated asymmetric Fe-N_(5)coordination structure anchored in defective g-C_(3)N_(4)(C_(3)N_(4)-Fe@rGO)is designed via an absorption-pyrolysis strategy.The two-dimensional(2D)conducting C_(3)N_(4)@graphene structure with abundant defect sites accelerates the trans-fer and transportation of lithium ions and electrons.The oversaturated asymmetric Fe-N_(5)coordination structure effectively improves the adsorbility of LiPSs and accelerates the redox kinetics of sulfur species.Hence,the Li-S cell with a C_(3)N_(4)-Fe@rGO modified separator reveals a high initial capacity(1197.1 mAh g^(-1) at 0.2 C)and a low capacity decay rate(0.037%per cycle after 900 cycles at 1 C).Even at high sulfur loading and extreme temperatures of 0℃,it also shows good cycling performance.This work creates ideas for synthesizing oversaturated single-atom coordination environments and an efficient route to the practical realization of the Li-S batteries.
基金supported by the Science and Technology Foundation of China Electric Power Research Institute(Development of high-energy-density alloy solid hydrogen storage materials,DG8323-002)。
文摘Metallic single-atom catalysts(SACs)have demonstrated high activity and potential in enhancing the hydrogen storage properties of MgH_(2).However,previous reports primarily focus on supported SACs,which often suffer from insufficient co ntact between single-atom active sites and hydrogen storage materials.In this study,the precursor Mo(CO)_(6)is uniformly dispersed on the surface of MgH_(2)via impregnation adsorption,leading to the formation of alloy-type Mo single atoms after hydrogenation/dehydrogenation activation.This alloy structure enables zero-distance contact between catalytic sites and the hydrogen storage material,facilitating electron exchange and hydrogen transfer between the Mo sites and MgH_(2).The MgH_(2)loaded with Mo single atoms(Mo_(1)-MgH_(2))exhibits excellent hydrogen absorption and desorption properties,with the initial hydrogen release temperature lowered from 323 to 218℃.At 250℃,Mo_(1)-MgH_(2)absorbs over 6.77 wt% of hydrogen within 1 min and releases over 5.85 wt% within 4 h.During 10 cycles of hydrogenation and dehydrogenation reactions,Mo_(1)-MgH_(2)maintains nearly 100% capacity and shows stable kinetics.This work provides new insights into the design and fabrication of catalysts for hydrogen storage materials.
基金Project supported by National Natural Science Foundation of China(22078159,U19B2001)。
文摘Hydroisomerization of n-alkanes plays an important role in fuel and lubricants processing.Bifunctional catalysts with ultralow platinum loading have recently been reported successively for hydroisomerisation.Herein,the catalysts were prepared successfully with different methods to improve the catalytic performance.The conversion of 0.01%Pt1@CeOx/SAPO-11 prepared by co-calcination method(0.01%Pt1@CS-c)is 71.4%,25%higher than the other prepared by precipitation method.The turnover frequency per active surface platinum site(TOFPt)of 0.01%Ptl@CS-c is as high as 13115 h^(-1).Revealed by the X-ray photoelectron spectroscopy(XPS)results,the quality of phase boundary/intersurface between ceria and zeolite is found significantly different.The conjunction quality of phase boundary directly affects the spillover rate of intermediate species,which further leads to an apparent activity difference.In addition,the possible role of ceria in the reaction is discussed,rather than just as a carrier for the active metal atoms.
基金supported by the National Key R&D Program of China(2024YFB4106400)National Natural Science Foundation of China(22209200,52302331)。
文摘Electrocatalytic reduction of carbon dioxide(CO_(2))to carbon monoxide(CO)is an effective strategy to achieve carbon neutrality.High selective and low-cost catalysts for the electrocatalytic reduction of CO_(2)have received increasing attention.In contrast to the conventional tube furnace method,the high-temperature shock(HTS)method enables ultra-fast thermal processing,superior atomic efficiency,and a streamlined synthesis protocol,offering a simplified method for the preparation of high-performance single-atom catalysts(SACs).The reports have shown that nickel-based SACs can be synthesized quickly and conveniently using the HTS method,making their application in CO_(2)reduction reactions(CO_(2)RR)a viable and promising avenue for further exploration.In this study,the effect of heating temperature,metal loading and different nitrogen(N)sources on the catalyst morphology,coordination environment and electrocatalytic performance were investigated.Under optimal conditions,0.05Ni-DCD-C-1050 showed excellent performance in reducing CO_(2)to CO,with CO selectivity close to 100%(−0.7 to−1.0 V vs RHE)and current density as high as 130 mA/cm^(2)(−1.1 V vs RHE)in a flow cell under alkaline environment.
