The susceptibility of Pt catalyst surfaces to carbon monoxide(CO)poisoning in anodic hydrogen oxidation reaction(HOR)has been a critical constraint on the development of proton exchange membrane fuel cells(PEMFCs).Eff...The susceptibility of Pt catalyst surfaces to carbon monoxide(CO)poisoning in anodic hydrogen oxidation reaction(HOR)has been a critical constraint on the development of proton exchange membrane fuel cells(PEMFCs).Effectively regulating the electronic structure of Pt to enhance CO resistance is crucial for developing high-performance catalysts with robust anti-poisoning capabilities.Herein,the Pt/W@NCNF featured by Pt nanoparticles and atomical dispersed tungsten(W)sites on N-doped carbon nanofibers is developed for CO tolerance HOR catalyst.The presence of W enables the electron transfer from Pt,which promotes electron rearrangement in the Pt-5d orbitals.It not only optimizes the adsorption of H^(*) and CO^(*)on Pt,but also the OH^(*) intermediates adsorbed on the W sites oxidize the CO*adsorbed on Pt,thereby retaining more active sites for H_(2) adsorption and oxidation.The HOR exchange current density of Pt/W@NCNF reaches 1.35 times that of commercial Pt/C,and the limiting current density decreases by only 3.4%after introducing 1000 ppm CO in H_(2).Notably,the Pt/W@NCNF-based PEMFCs deliver markedly superior performance across a range of CO concentrations.The present study demonstrates that electronic modulation of Pt is an effective strategy for simultaneously achieving resistance to CO and promoted HOR activity.展开更多
Metal nanoclusters with well-defined atomic structures offer significant promise in the field of catalysis due to their sub-nanometer size and tunable organic-inorganic hybrid structural features.Herein,we successfull...Metal nanoclusters with well-defined atomic structures offer significant promise in the field of catalysis due to their sub-nanometer size and tunable organic-inorganic hybrid structural features.Herein,we successfully synthesized an 11-core copper(Ⅰ)-alkynyl nanocluster(Cu11),which is stabilized by alkynyl ligands derived from a photosensitive rhodamine dye molecule.Notably,this Cu11cluster exhibited excellent photocatalytic hydrogen evolution activity(8.13 mmol g-1h-1)even in the absence of a mediator and noble metal co-catalyst.Furthermore,when Cu11clusters were loaded onto the surface of TiO_(2)nanosheets,the resultant Cu11@TiO_(2)nanocomposites exhibited a significant enhancement in hydrogen evolution efficiency,which is 60 times higher than that of pure TiO_(2)nanosheets.The incorporation of Cu11clusters within the Cu11@TiO_(2)effectively inhibits the recombination of photogenerated electrons and holes,thereby accelerating the charge separation and migration in the composite material.This work introduces a novel perspective for designing highly active copper cluster-based photocatalysts.展开更多
Single-atom catalysts(SACs)have demonstrated exceptional performance in electrocatalytic water splitting,owing to their maximized atomic utilization efficiency and superior reaction kinetics.The incorporation of SACs ...Single-atom catalysts(SACs)have demonstrated exceptional performance in electrocatalytic water splitting,owing to their maximized atomic utilization efficiency and superior reaction kinetics.The incorporation of SACs typically depends on robust metal-support interactions,which stabilize the single atoms on the support through various unsaturated chemical sites or spatial confinement.A critical challenge lies in precisely modulating the electronic structure and coordination environment of metal atoms.However,current research primarily focuses on single-atom metals,often neglecting the significant role of support materials in SACs.Two-dimensional(2D)atomically thin materials(ATMs)possess unique physicochemical properties and tunable reaction environments,which can modulate catalytic performance via metal-support interactions,positioning them as promising platforms for SAC loading.This paper reviews the recent advancements and the current status of SACs supported on 2D ATMs(SACs@ATMs).The structural design theory and synthesis strategies of SACs@ATMs are systematically discussed.The significance of advanced characterization techniques in elucidating the coordination environment and metal-support interactions is highlighted.Additionally,the reaction mechanisms and applications of SACs in electrocatalytic water splitting are summarized.Finally,the future challenges and opportunities for SACs@ATMs are outlined.This paper aims to provide insights and guidance for the rational design of SACs@ATMs with high-performance electrocatalytic water splitting capabilities.展开更多
Atomically precise metal nanoclusters are an emerging type of nanomaterial which has diverse interfacial metal-ligand coordination motifs that can significantly affect their physicochemical properties and functionalit...Atomically precise metal nanoclusters are an emerging type of nanomaterial which has diverse interfacial metal-ligand coordination motifs that can significantly affect their physicochemical properties and functionalities.Among that,Cu nanoclusters have been gaining continuous increasing research attentions,thanks to the low cost,diversified structures,and superior catalytic performance for various reactions.In this review,we first summarize the recent progress regarding the synthetic methods of atomically precise Cu nanoclusters and the coordination modes between Cu and several typical ligands and then discuss the catalytic applications of these Cu nanoclusters with some explicit examples to explain the atomical-level structure-performance relationship.Finally,the current challenges and future research perspectives with some critical thoughts are elaborated.We hope this review can not only provide a whole picture of the current advances regarding the synthesis and catalytic applications of atomically precise Cu nanoclusters,but also points out some future research visions in this rapidly booming field.展开更多
Atomically dispersed metal site(ADMS)materials have emerged as a promising class of materials for electrocatalysis reactions in the field of energy conversion.Characterized by individual metal atoms dispersed on suita...Atomically dispersed metal site(ADMS)materials have emerged as a promising class of materials for electrocatalysis reactions in the field of energy conversion.Characterized by individual metal atoms dispersed on suitable supports,ADMS materials provide unique catalytic sites with highly tunable electronic structures.This review summarizes recent advancements in the field,with a focus on the critical roles of support materials,coordination environments,and the mechanisms underlying catalytic activity at the atomic level.First,commonly used density functional theory(DFT)simulations are reviewed,emphasizing their pivotal role in elucidating reaction mechanisms and predicting the behavior of ADMS in electrochemical reactions for hydrogen energy utilization.Then,advancements in ADMS for half-cell electrochemical reactions,including oxygen evolution reaction,hydrogen evolution reaction,and oxygen reduction reaction,as well as their applications in fuel cells and water splitting,are summarized.Finally,the challenges and future prospects of ADMS are discussed.This review underscores the transformative potential of ADMS in electrocatalysis,paving the way for innovative and sustainable energy conversion technologies.展开更多
Conventional gas sensing materials(e.g.,metal oxides)suffer from deficient sensitivity and serve cross-sensitivity issues due to the lack of efficient adsorption sites.Herein,the heteroatom atomically doping strategy ...Conventional gas sensing materials(e.g.,metal oxides)suffer from deficient sensitivity and serve cross-sensitivity issues due to the lack of efficient adsorption sites.Herein,the heteroatom atomically doping strategy is demonstrated to significantly enhance the sensing performance of metal oxides-based gas sensing materials.Specifically,the Sn atoms were incorporated into porous Fe_(2)O_(3)in the form of atomically dispersed sites.As revealed by X-ray absorption spectroscopy and atomic-resolution scanning transmission electron microscopy,these Sn atoms successfully occupy the Fe sites in the Fe_(2)O_(3)lattice,forming the unique Sn-O-Fe sites.Compared to Fe-O-Fe sites(from bare Fe_(2)O_(3))and Sn-O-Sn sites(from SnO_(2)/Fe_(2)O_(3)with high Sn loading),the Sn-O-Fe sites on porous Fe_(2)O_(3)exhibit a superior sensitivity(Rg/Ra=2646.6)to 1 ppm NO_(2),along with dramatically increased selectivity and ultra-low limits of detection(10 ppb).Further theoretical calculations suggest that the strong adsorption of NO_(2)on Sn-O-Fe sites(N atom on Sn site,O atom on Fe site)contributes a more efficient gas response,compared to NO_(2)on Fe-O-Fe sites and other gases on Sn-O-Fe sites.Moreover,the incorporated Sn atoms reduce the bandgap of Fe_(2)O_(3),not only facilitating the electron release but also increasing the NO_(2)adsorption at a low working temperature(150°C).This work introduces an effective strategy to construct effective adsorption sites that show a unique response to specific gas molecules,potentially promoting the rational design of atomically modified gas sensing materials with high sensitivity and high selectivity.展开更多
Propylene,a pivotal chemical feedstock,is extensively used in synthesizing high-value derivatives such as polypropylene and acrylonitrile[1].Although propylene is predominantly produced via naphtha cracking,a persiste...Propylene,a pivotal chemical feedstock,is extensively used in synthesizing high-value derivatives such as polypropylene and acrylonitrile[1].Although propylene is predominantly produced via naphtha cracking,a persistent supply-demand gap exists[2].Non-oil routes,such as propane dehydrogenation(PDH),are increasingly attractive,particularly with the availability of shale gas[3].Modern non-oxidative PDH heavily relies on Pt nanoparticle catalysts promoted with SnOx(e.g.,PtSn/Al2O3 used in Honeywell UOP's Oleflex process)[4].However,these systems suffer from inherent limitations:high Pt costs,coke formation via deep dehydrogenation,and sintering during regeneration-necessitating environmentally detrimental oxychlorination treatments to restore activity[5].展开更多
Herein,an oxygen-doped porous g-C_(3)N_(4)photocatalyst modified with atomically dispersed Fe(Fe_(1)/OPCN)issuccessfully prepared and exhibits significant superiority in removing refractory sulfonic azo contaminants f...Herein,an oxygen-doped porous g-C_(3)N_(4)photocatalyst modified with atomically dispersed Fe(Fe_(1)/OPCN)issuccessfully prepared and exhibits significant superiority in removing refractory sulfonic azo contaminants fromwater via catalyst-contaminant interaction.The elimination performance of Fe_(1)/OPCN towards acid red 9,acidred 13 and amaranth containing similar azonaphthalene structure and increasing sulfonic acid groups increasesgradually.The amaranth degradation rate of Fe_(1)/OPCN is 17.7 and 6.1 times as that of homogeneous Fenton andOPCN,respectively.In addition,Fe_(1)/OPCN also has more outstanding removal activities towards other con-taminantswith sulfonic acid and azo groups alone.The considerable enhancement for removing sulfonic azocontaminants of Fe_(1)/OPCN is mainly ascribed to the following aspects:(1)The modified Fe could enhance theadsorption towards sulfonic azo compounds to accelerate the mass transfer,act as e^(-)acceptor to promoteinterfacial charge separation,and trigger the self-Fenton reaction to convert in-situ generated H_(2)O_(2)into·OH.(2)Fe(Ⅲ)could coordinate with-N=N-to form d-πconjugation,which could attract e^(-)transfer to attack-N=N-bond.Meanwhile,the inhibited charge recombination could release more free h^(þ)to oxidize sulfonicacid groups into SO4^(-)·.(3)Under the cooperation of abundant multiple active species(·O_(2)^(-),h^(þ),e^(-),·OH,SO4^(-)·)formed during the degradation reaction,sulfonic azo compounds could be completely mineralized into harmlesssmall molecules(CO_(2),H_(2)O,etc.)by means of-N=N-cleavage,hydroxyl substitution,and aromatic ringopening.This work offers a novel approach for effectively eliminating refractory sulfonic azo compounds fromwastewater.展开更多
Atomically precise palladium(Pd)clusters are emerging as versatile nanomaterials with applications in catalysis and biomedicine.This study explores the synthesis,structure evolution,and catalytic properties of Pd clus...Atomically precise palladium(Pd)clusters are emerging as versatile nanomaterials with applications in catalysis and biomedicine.This study explores the synthesis,structure evolution,and catalytic properties of Pd clusters stabilized by cyclohexanethiol(HSC_(6)H_(11))ligands.Using electrospray ionization mass spectrometry(ESI-MS)and single-crystal X-ray diffraction(SXRD),structures of the Pd clusters ranging from Pd4(SC_(6)H_(11))8 to Pd18(SC_(6)H_(11))36 were determined.This analysis revealed a structure evolution from polygonal to elliptical geometries of the PdnS2n frameworks as the cluster size increased.UV-Vis-NIR spectroscopy,combined with quantum chemical calculations,elucidated changes in the electronic structure of the clusters.Catalytic studies on the Sonogashira cross-coupling reactions demonstrated a size-dependent decline in activity attributed to variations in structural arrangements and electronic properties.Mechanistic insights proposed a distinctive Pd(Ⅱ)-Pd(Ⅳ)catalytic cycle.This research underscores how ligands and cluster size influence the structures and properties of Pd clusters,offering valuable insights for the future design and application of Pd clusters in advanced catalysis and beyond.展开更多
Metal-based catalysts are prevalent in the CO_(2) hydrogenation to methanol owing to their remarkable catalytic activity.Herein,Ru/In_(2)O_(3) catalysts with different morphologies obtained by doping Ru into In_(2)O_(...Metal-based catalysts are prevalent in the CO_(2) hydrogenation to methanol owing to their remarkable catalytic activity.Herein,Ru/In_(2)O_(3) catalysts with different morphologies obtained by doping Ru into In_(2)O_(3) with irregular,rod-like,and flower-like morphologies are used for catalytic CO_(2) hydrogenation to methanol.Results indicate that the flower-like Ru/In_(2)O_(3)(Ru/In_(2)O_(3)-F)exhibits higher catalytic performance than Ru/In_(2)O_(3) with other morphologies,achieving a 12.9%CO_(2) conversion,74.02%methanol selectivity,and 671.36 mg_(MeOH) h^(−1) g_(cat)^(−1) methanol spatiotemporal yield.Furthermore,Ru/In_(2)O_(3)-F maintains its catalytic stability over 200 h at 5 MPa and 290℃.The promotional effect mainly stems from the fact that electronic structure of Ru can be effectively adjusted by modulating the morphology of In_(2)O_(3).The strong interaction between atomically dispersed Ru and In_(2)O_(3)-F enhances the structural stability of Ru,inhibiting the agglomeration of the catalyst during the reaction process.Furthermore,density-functional theory calculations reveal that highly dispersed Ru atoms not only perform efficient and rapid electronic gain and loss processes,facilitating the catalytic activation of H_(2) into H intermediates.It also enables the generated reactive H to rapidly overflow to the surrounding In sites to participate in CO_(2) reduction.These findings provide a theoretical basis for the development of high-performance catalysts for CO_(2) hydrogenation.展开更多
Efficient CO_(2)photoreduction to produce fuel remains a great challenge,due to the fast recombination of photogenerated charge carriers and the lack of effective reactive sites in the developed photocatalysts.Herein,...Efficient CO_(2)photoreduction to produce fuel remains a great challenge,due to the fast recombination of photogenerated charge carriers and the lack of effective reactive sites in the developed photocatalysts.Herein,single Co atoms(Co_(SA))were highly dispersed on hydrothermally synthesized BiOCl nanosheets(BOC)by a facile two-step electrostatic self-assembly and pyrolysis method.The obtained Co_(SA)-BOC could be performed for efficient CO_(2)photoreduction to stoichiometrically produce CO and O_(2)at the ratio of 2:1,with the CO evolution rate reaching 45.93 μmol g^(-1)h^(-1),~4 times that of the pristine BOC.This distinctly improved photocatalytic performance for Co_(SA)-BOC should benefit from the introduction of atomically dispersed Co–O_(4)coordination structures,which could accelerate the migration of photogenerated charge carriers to surface by creating an impurity energy level in the forbidden band,and act as the reactive sites to deliver the photogenerated electrons to activate CO_(2)molecules for CO production.This work provides a facile and reliable strategy to highly disperse single atoms on low-dimensional semiconductors for efficient CO_(2)photoreduction to selectively produce CO.展开更多
Atomically dispersed catalysts exhibit significant influence on facilitating the sluggish oxygen reduction reaction(ORR)kinetics with high atom economy,owing to remarkable attributes including nearly 100%atomic utiliz...Atomically dispersed catalysts exhibit significant influence on facilitating the sluggish oxygen reduction reaction(ORR)kinetics with high atom economy,owing to remarkable attributes including nearly 100%atomic utilization and exceptional catalytic functionality.Furthermore,accurately controlling atomic physical properties including spin,charge,orbital,and lattice degrees of atomically dispersed catalysts can realize the optimized chemical properties including maximum atom utilization efficiency,homogenous active centers,and satisfactory catalytic performance,but remains elusive.Here,through physical and chemical insight,we review and systematically summarize the strategies to optimize atomically dispersed ORR catalysts including adjusting the atomic coordination environment,adjacent electronic orbital and site density,and the choice of dual-atom sites.Then the emphasis is on the fundamental understanding of the correlation between the physical property and the catalytic behavior for atomically dispersed catalysts.Finally,an overview of the existing challenges and prospects to illustrate the current obstacles and potential opportunities for the advancement of atomically dispersed catalysts in the realm of electrocatalytic reactions is offered.展开更多
Although nanozymes have been widely developed,accurate design of highly active sites at the atomic level to mimic the electronic and geometrical structure of enzymes and the exploration of underlying mechanisms still ...Although nanozymes have been widely developed,accurate design of highly active sites at the atomic level to mimic the electronic and geometrical structure of enzymes and the exploration of underlying mechanisms still face significant challenges.Herein,two functional groups with opposite electron modulation abilities(nitro and amino)were introduced into the metal–organic frameworks(MIL-101(Fe))to tune the atomically dispersed metal sites and thus regulate the enzymelike activity.Notably,the functionalization of nitro can enhance the peroxidase(POD)-like activity of MIL-101(Fe),while the amino is poles apart.Theoretical calculations demonstrate that the introduction of nitro can not only regulate the geometry of adsorbed intermediates but also improve the electronic structure of metal active sites.Benefiting from both geometric and electronic effects,the nitro-functionalized MIL-101(Fe)with a low reaction energy barrier for the HO*formation exhibits a superior POD-like activity.As a concept of the application,a nitro-functionalized MIL-101(Fe)-based biosensor was elaborately applied for the sensitive detection of acetylcholinesterase activity in the range of 0.2–50 mU mL−1 with a limit of detection of 0.14 mU mL−1.Moreover,the detection of organophosphorus pesticides was also achieved.This work not only opens up new prospects for the rational design of highly active nanozymes at the atomic scale but also enhances the performance of nanozyme-based biosensors.展开更多
Rechargeable zinc-air batteries(ZABs)are currently receiving extensive attention because of their extremely high theoretical specific energy density,low manufacturing costs,and environmental friendliness.Exploring bif...Rechargeable zinc-air batteries(ZABs)are currently receiving extensive attention because of their extremely high theoretical specific energy density,low manufacturing costs,and environmental friendliness.Exploring bifunctional catalysts with high activity and stability to overcome sluggish kinetics of oxygen reduction reaction and oxygen evolution reaction is critical for the development of rechargeable ZABs.Atomically dispersed metal-nitrogen-carbon(M-N-C)catalysts possessing prominent advantages of high metal atom utilization and electrocatalytic activity are promising candidates to promote oxygen electrocatalysis.In this work,general principles for designing atomically dispersed M-N-C are reviewed.Then,strategies aiming at enhancing the bifunctional catalytic activity and stability are presented.Finally,the challenges and perspectives of M-N-C bifunctional oxygen catalysts for ZABs are outlined.It is expected that this review will provide insights into the targeted optimization of atomically dispersed M-N-C catalysts in rechargeable ZABs.展开更多
Heterogeneous catalysts with ultra-small clusters and atomically dispersed(USCAD)active sites have gained increasing attention in recent years.However,developing USCAD catalysts with high-density metal sites anchored ...Heterogeneous catalysts with ultra-small clusters and atomically dispersed(USCAD)active sites have gained increasing attention in recent years.However,developing USCAD catalysts with high-density metal sites anchored in porous nanomaterials is still challenging.Here,through the template-free S-assisted pyrolysis of low-cost Fe-salts with melamine(MA),porous alveolate Fe/g-C3N4 catalysts with high-density(Fe loading up to 17.7 wt%)and increased USCAD Fe sites were synthesized.The presence of a certain amount of S species in the Fe-salts/MA system plays an important role in the formation of USCAD S-Fe-salt/CN catalysts;the S species act as a"sacrificial carrier"to increase the dispersion of Fe species through Fe-S coordination and generate porous alveolate structure by escaping in the form of SO2 during pyrolysis.The S-Fe-salt/CN catalysts exhibit greatly promoted activity and reusability for degrading various organic pollutants in advanced oxidation processes compared to the corresponding Fe-salt/CN catalysts,due to the promoted accessibility of USCAD Fe sites by the porous alveolate structure.This S-assisted method exhibits good feasibility in a large variety of S species(thiourea,S powder,and NH4SCN)and Fe salts,providing a new avenue for the low-cost and large-scale synthesis of high-density USCAD metal/g-C3N4 catalysts.展开更多
The real structure and in situ evolution of catalysts under working conditions are of paramount importance,especially for bifunctional electrocatalysis.Here,we report asymmetric structural evolution and dynamic hydrog...The real structure and in situ evolution of catalysts under working conditions are of paramount importance,especially for bifunctional electrocatalysis.Here,we report asymmetric structural evolution and dynamic hydrogen-bonding promotion mechanism of an atomically dispersed electrocatalyst.Pyrolysis of Co/Ni-doped MAF-4/ZIF-8 yielded nitrogen-doped porous carbons functionalized by atomically dispersed Co–Ni dual-metal sites with an unprecedented N8V4 structure,which can serve as an efficient bifunctional electrocatalyst for overall water splitting.More importantly,the electrocatalyst showed remarkable activation behavior due to the in situ oxidation of the carbon substrate to form C–OH groups.Density functional theory calculations suggested that the flexible C–OH groups can form reversible hydrogen bonds with the oxygen evolution reaction intermediates,giving a bridge between elementary reactions to break the conventional scaling relationship.展开更多
It is challenging to create cation vacancies in electrode materials for enhancing the performance of rechargeable lithium ion batteries (LIBs). Herein, we utilized a strong alkaline etching method to successfully crea...It is challenging to create cation vacancies in electrode materials for enhancing the performance of rechargeable lithium ion batteries (LIBs). Herein, we utilized a strong alkaline etching method to successfully create Co vacancies at the interface of atomically thin Co_(3−x)O_(4)/graphene@CNT heterostructure for high-energy/power lithium storage. The creation of Co-vacancies in the sample was confirmed by high-resolution scanning transmission electron microscope (HRSTEM), X-ray photoelectron spectroscopy (XPS) and electron energy loss near-edge structures (ELNES). The obtained Co_(3−x)O_(4)/graphene@CNT delivers an ultra-high capacity of 1688.2 mAh g^(−1) at 0.2 C, excellent rate capability of 83.7% capacity retention at 1 C, and an ultralong life up to 1500 cycles with a reversible capacity of 1066.3 mAh g^(−1). Reaction kinetic study suggests a significant contribution from pseudocapacitive storage induced by the Co-vacancies at the Co_(3−x)O_(4)/graphene@CNT interface. Density functional theory confirms that the Co-vacancies could dramatically enhance the Li adsorption and provide an additional pathway with a lower energy barrier for Li diffusion, which results in an intercalation pseudocapacitive behavior and high-capacity/rate energy storage.展开更多
Atomically thin two-dimensional （2D） layered materials have potential applications in nanoelectronics, nanophoton- ics, and integrated optoelectronics. Band gap engineering of these 2D semiconductors is critical for...Atomically thin two-dimensional （2D） layered materials have potential applications in nanoelectronics, nanophoton- ics, and integrated optoelectronics. Band gap engineering of these 2D semiconductors is critical for their broad applications in high-performance integrated devices, such as broad-band photodetectors, multi-color light emitting diodes （LEDs）, and high-efficiency photovoltaic devices. In this review, we will summarize the recent progress on the controlled growth of composition modulated atomically thin 2D semiconductor alloys with band gaps tuned in a wide range, as well as their induced applications in broadly tunable optoelectronic components. The band gap engineered 2D semiconductors could open up an exciting opportunity for probing their fundamental physical properties in 2D systems and may find diverse applications in functional electronic/optoelectronic devices.展开更多
Metal silicate hydroxides have been recognized as efficient oxygen evolution reaction(OER)electrocatalysts,yet tailoring of their intrinsic activity remains confused.Herein,Fe had been incorporated into cobalt silicat...Metal silicate hydroxides have been recognized as efficient oxygen evolution reaction(OER)electrocatalysts,yet tailoring of their intrinsic activity remains confused.Herein,Fe had been incorporated into cobalt silicate hydroxide nanosheets and the resulted material achieves a competitive OER catalytic activity.It is found that the doping state obviously affects the electrical transport property.Specifically,highly dispersed Fe atoms(low-concentration Fe doping)trigger slight electron transfer to Co atoms while serried Fe(highconcentration Fe doping)attract vast electrons.By introducing 6 at.%Fe doping,partial relatively inert Co sites are activated by atomically dispersed Fe,bearing an optimal metal 3d electronic occupation and adsorption capacity to oxygen intermediate.The introduced Co-O-Fe unit trigger the p-donation effect and decrease the number of electrons in p*-antibonding orbitals,which enhance the Fe-O covalency and the structural stability.As a result,the sample delivers a low overpotential of 293 mV to achieve a current density of 10 mA cm^(-2).This work clarifies the superiority of atomically dispersed doping state,which is of fundamental interest to the design of doped catalyst.展开更多
Oxygen reduction reaction(ORR)is the key reaction at the cathode of proton exchange membrane fuel cells(PEMFCs)and metal-air batteries(1)To address the challenges associated with Pt-based electrocatalysts having promi...Oxygen reduction reaction(ORR)is the key reaction at the cathode of proton exchange membrane fuel cells(PEMFCs)and metal-air batteries(1)To address the challenges associated with Pt-based electrocatalysts having prominent activity for ORR,e.g.scarce abundance,prohibitive cost,poor stability,and vulnerability to reaction intermediates,it is necessary to explore other cost-effective ORR electrocatalysts with competitive or even superior performance to promote the commercialization of the energy conversion devices.展开更多
基金supported by the National Natural Science Foundation of China(22179034,22279030)the Natural Science Foundation of Heilongjiang Province(ZD2023B002).
文摘The susceptibility of Pt catalyst surfaces to carbon monoxide(CO)poisoning in anodic hydrogen oxidation reaction(HOR)has been a critical constraint on the development of proton exchange membrane fuel cells(PEMFCs).Effectively regulating the electronic structure of Pt to enhance CO resistance is crucial for developing high-performance catalysts with robust anti-poisoning capabilities.Herein,the Pt/W@NCNF featured by Pt nanoparticles and atomical dispersed tungsten(W)sites on N-doped carbon nanofibers is developed for CO tolerance HOR catalyst.The presence of W enables the electron transfer from Pt,which promotes electron rearrangement in the Pt-5d orbitals.It not only optimizes the adsorption of H^(*) and CO^(*)on Pt,but also the OH^(*) intermediates adsorbed on the W sites oxidize the CO*adsorbed on Pt,thereby retaining more active sites for H_(2) adsorption and oxidation.The HOR exchange current density of Pt/W@NCNF reaches 1.35 times that of commercial Pt/C,and the limiting current density decreases by only 3.4%after introducing 1000 ppm CO in H_(2).Notably,the Pt/W@NCNF-based PEMFCs deliver markedly superior performance across a range of CO concentrations.The present study demonstrates that electronic modulation of Pt is an effective strategy for simultaneously achieving resistance to CO and promoted HOR activity.
基金supported by the National Natural Science Foundation of China(Nos.22371263 and U2004193)Natural Science Foundation of Henan Province(No.232300421225)。
文摘Metal nanoclusters with well-defined atomic structures offer significant promise in the field of catalysis due to their sub-nanometer size and tunable organic-inorganic hybrid structural features.Herein,we successfully synthesized an 11-core copper(Ⅰ)-alkynyl nanocluster(Cu11),which is stabilized by alkynyl ligands derived from a photosensitive rhodamine dye molecule.Notably,this Cu11cluster exhibited excellent photocatalytic hydrogen evolution activity(8.13 mmol g-1h-1)even in the absence of a mediator and noble metal co-catalyst.Furthermore,when Cu11clusters were loaded onto the surface of TiO_(2)nanosheets,the resultant Cu11@TiO_(2)nanocomposites exhibited a significant enhancement in hydrogen evolution efficiency,which is 60 times higher than that of pure TiO_(2)nanosheets.The incorporation of Cu11clusters within the Cu11@TiO_(2)effectively inhibits the recombination of photogenerated electrons and holes,thereby accelerating the charge separation and migration in the composite material.This work introduces a novel perspective for designing highly active copper cluster-based photocatalysts.
基金financially supported by the National Oversea Postdoctoral Talent Attraction Programthe Pilot Group Program of the Research Fund for International Senior Scientists(52350710795)the Youth Fund of the National Natural Science Foundation of China(52402288).
文摘Single-atom catalysts(SACs)have demonstrated exceptional performance in electrocatalytic water splitting,owing to their maximized atomic utilization efficiency and superior reaction kinetics.The incorporation of SACs typically depends on robust metal-support interactions,which stabilize the single atoms on the support through various unsaturated chemical sites or spatial confinement.A critical challenge lies in precisely modulating the electronic structure and coordination environment of metal atoms.However,current research primarily focuses on single-atom metals,often neglecting the significant role of support materials in SACs.Two-dimensional(2D)atomically thin materials(ATMs)possess unique physicochemical properties and tunable reaction environments,which can modulate catalytic performance via metal-support interactions,positioning them as promising platforms for SAC loading.This paper reviews the recent advancements and the current status of SACs supported on 2D ATMs(SACs@ATMs).The structural design theory and synthesis strategies of SACs@ATMs are systematically discussed.The significance of advanced characterization techniques in elucidating the coordination environment and metal-support interactions is highlighted.Additionally,the reaction mechanisms and applications of SACs in electrocatalytic water splitting are summarized.Finally,the future challenges and opportunities for SACs@ATMs are outlined.This paper aims to provide insights and guidance for the rational design of SACs@ATMs with high-performance electrocatalytic water splitting capabilities.
基金supported by the open funds of Key Laboratory of Functional Inorganic Material Chemistry (Heilongjiang University), Ministry of Education, Chinathe funding from Guangdong Natural Science Funds (No. 2023A0505050107)。
文摘Atomically precise metal nanoclusters are an emerging type of nanomaterial which has diverse interfacial metal-ligand coordination motifs that can significantly affect their physicochemical properties and functionalities.Among that,Cu nanoclusters have been gaining continuous increasing research attentions,thanks to the low cost,diversified structures,and superior catalytic performance for various reactions.In this review,we first summarize the recent progress regarding the synthetic methods of atomically precise Cu nanoclusters and the coordination modes between Cu and several typical ligands and then discuss the catalytic applications of these Cu nanoclusters with some explicit examples to explain the atomical-level structure-performance relationship.Finally,the current challenges and future research perspectives with some critical thoughts are elaborated.We hope this review can not only provide a whole picture of the current advances regarding the synthesis and catalytic applications of atomically precise Cu nanoclusters,but also points out some future research visions in this rapidly booming field.
基金supported by the National Natural Science Foundation of China(22005072,21965006)Guizhou Provincial Key Technology R&D Program(Qian Ke He support(2023)General 122)+3 种基金Guiyang Guian Science and Technology Personnel Training Project([2024]2-13)Youth Science and Technology Talent Development Project from Guizhou Provincial Department of Education(KY[2022]163)Guizhou Provincial Science and Technology Foundation(KYJZ[2024]029)the ETS Marcelle-Gauvreau Engineering Research Chair program.
文摘Atomically dispersed metal site(ADMS)materials have emerged as a promising class of materials for electrocatalysis reactions in the field of energy conversion.Characterized by individual metal atoms dispersed on suitable supports,ADMS materials provide unique catalytic sites with highly tunable electronic structures.This review summarizes recent advancements in the field,with a focus on the critical roles of support materials,coordination environments,and the mechanisms underlying catalytic activity at the atomic level.First,commonly used density functional theory(DFT)simulations are reviewed,emphasizing their pivotal role in elucidating reaction mechanisms and predicting the behavior of ADMS in electrochemical reactions for hydrogen energy utilization.Then,advancements in ADMS for half-cell electrochemical reactions,including oxygen evolution reaction,hydrogen evolution reaction,and oxygen reduction reaction,as well as their applications in fuel cells and water splitting,are summarized.Finally,the challenges and future prospects of ADMS are discussed.This review underscores the transformative potential of ADMS in electrocatalysis,paving the way for innovative and sustainable energy conversion technologies.
基金supported by the National Key Research and Development Project of China(Grant No.2022YFB3205500)the National Natural Science Foundation of China(Grant No.12275190,12105201)+2 种基金Jiangsu Funding Program for Excellent Postdoctoral Talent(Grant No.2024ZB723)the Shenzhen Research Funding Program(JCYJ20230807154402004)supported by the Collaborative Innovation Center of Suzhou Nano Science&Technology,the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),the 111 Project,the Joint International Research Laboratory of Carbon-Based Functional Materials and Devices,and the Suzhou Key Laboratory of Functional Nano&Soft Materials and Soochow University-Western University Centre for Synchrotron Radiation Research.
文摘Conventional gas sensing materials(e.g.,metal oxides)suffer from deficient sensitivity and serve cross-sensitivity issues due to the lack of efficient adsorption sites.Herein,the heteroatom atomically doping strategy is demonstrated to significantly enhance the sensing performance of metal oxides-based gas sensing materials.Specifically,the Sn atoms were incorporated into porous Fe_(2)O_(3)in the form of atomically dispersed sites.As revealed by X-ray absorption spectroscopy and atomic-resolution scanning transmission electron microscopy,these Sn atoms successfully occupy the Fe sites in the Fe_(2)O_(3)lattice,forming the unique Sn-O-Fe sites.Compared to Fe-O-Fe sites(from bare Fe_(2)O_(3))and Sn-O-Sn sites(from SnO_(2)/Fe_(2)O_(3)with high Sn loading),the Sn-O-Fe sites on porous Fe_(2)O_(3)exhibit a superior sensitivity(Rg/Ra=2646.6)to 1 ppm NO_(2),along with dramatically increased selectivity and ultra-low limits of detection(10 ppb).Further theoretical calculations suggest that the strong adsorption of NO_(2)on Sn-O-Fe sites(N atom on Sn site,O atom on Fe site)contributes a more efficient gas response,compared to NO_(2)on Fe-O-Fe sites and other gases on Sn-O-Fe sites.Moreover,the incorporated Sn atoms reduce the bandgap of Fe_(2)O_(3),not only facilitating the electron release but also increasing the NO_(2)adsorption at a low working temperature(150°C).This work introduces an effective strategy to construct effective adsorption sites that show a unique response to specific gas molecules,potentially promoting the rational design of atomically modified gas sensing materials with high sensitivity and high selectivity.
文摘Propylene,a pivotal chemical feedstock,is extensively used in synthesizing high-value derivatives such as polypropylene and acrylonitrile[1].Although propylene is predominantly produced via naphtha cracking,a persistent supply-demand gap exists[2].Non-oil routes,such as propane dehydrogenation(PDH),are increasingly attractive,particularly with the availability of shale gas[3].Modern non-oxidative PDH heavily relies on Pt nanoparticle catalysts promoted with SnOx(e.g.,PtSn/Al2O3 used in Honeywell UOP's Oleflex process)[4].However,these systems suffer from inherent limitations:high Pt costs,coke formation via deep dehydrogenation,and sintering during regeneration-necessitating environmentally detrimental oxychlorination treatments to restore activity[5].
基金supported by the Natural Science Foundation of Jiangsu Province(BK20221541)National Natural Science Foundation of China(21707052)Jiangsu Agriculture Science and Technology Innovation Fund(CX(20)3108).
文摘Herein,an oxygen-doped porous g-C_(3)N_(4)photocatalyst modified with atomically dispersed Fe(Fe_(1)/OPCN)issuccessfully prepared and exhibits significant superiority in removing refractory sulfonic azo contaminants fromwater via catalyst-contaminant interaction.The elimination performance of Fe_(1)/OPCN towards acid red 9,acidred 13 and amaranth containing similar azonaphthalene structure and increasing sulfonic acid groups increasesgradually.The amaranth degradation rate of Fe_(1)/OPCN is 17.7 and 6.1 times as that of homogeneous Fenton andOPCN,respectively.In addition,Fe_(1)/OPCN also has more outstanding removal activities towards other con-taminantswith sulfonic acid and azo groups alone.The considerable enhancement for removing sulfonic azocontaminants of Fe_(1)/OPCN is mainly ascribed to the following aspects:(1)The modified Fe could enhance theadsorption towards sulfonic azo compounds to accelerate the mass transfer,act as e^(-)acceptor to promoteinterfacial charge separation,and trigger the self-Fenton reaction to convert in-situ generated H_(2)O_(2)into·OH.(2)Fe(Ⅲ)could coordinate with-N=N-to form d-πconjugation,which could attract e^(-)transfer to attack-N=N-bond.Meanwhile,the inhibited charge recombination could release more free h^(þ)to oxidize sulfonicacid groups into SO4^(-)·.(3)Under the cooperation of abundant multiple active species(·O_(2)^(-),h^(þ),e^(-),·OH,SO4^(-)·)formed during the degradation reaction,sulfonic azo compounds could be completely mineralized into harmlesssmall molecules(CO_(2),H_(2)O,etc.)by means of-N=N-cleavage,hydroxyl substitution,and aromatic ringopening.This work offers a novel approach for effectively eliminating refractory sulfonic azo compounds fromwastewater.
基金supported by the Start-Up Research Funding of Fujian Normal University(No.Y0720326K13)the National Natural Science Foundation of China(Nos.22103035 and 22033005)+2 种基金the National Key R&D Program of China(No.2022YFA1503900)Shenzhen Science and Technology Program(No.RCYX20231211090357078)Guangdong Provincial Key Laboratory of Catalysis(No.2020B121201002).
文摘Atomically precise palladium(Pd)clusters are emerging as versatile nanomaterials with applications in catalysis and biomedicine.This study explores the synthesis,structure evolution,and catalytic properties of Pd clusters stabilized by cyclohexanethiol(HSC_(6)H_(11))ligands.Using electrospray ionization mass spectrometry(ESI-MS)and single-crystal X-ray diffraction(SXRD),structures of the Pd clusters ranging from Pd4(SC_(6)H_(11))8 to Pd18(SC_(6)H_(11))36 were determined.This analysis revealed a structure evolution from polygonal to elliptical geometries of the PdnS2n frameworks as the cluster size increased.UV-Vis-NIR spectroscopy,combined with quantum chemical calculations,elucidated changes in the electronic structure of the clusters.Catalytic studies on the Sonogashira cross-coupling reactions demonstrated a size-dependent decline in activity attributed to variations in structural arrangements and electronic properties.Mechanistic insights proposed a distinctive Pd(Ⅱ)-Pd(Ⅳ)catalytic cycle.This research underscores how ligands and cluster size influence the structures and properties of Pd clusters,offering valuable insights for the future design and application of Pd clusters in advanced catalysis and beyond.
基金financially supported by the Key Laboratory of Carbon-based Energy Molecular Chemical Utilization Technology in Guizhou Province(No.2023008)Guizhou Provincial Science and Technology Projects(No.ZKZD2023004)+1 种基金One Hundred Person Project of Guizhou Province(No.GCC 2023013)Scientific and Technological Innovation Talents Team Project of Guizhou Province(No.CXTD2023029).
文摘Metal-based catalysts are prevalent in the CO_(2) hydrogenation to methanol owing to their remarkable catalytic activity.Herein,Ru/In_(2)O_(3) catalysts with different morphologies obtained by doping Ru into In_(2)O_(3) with irregular,rod-like,and flower-like morphologies are used for catalytic CO_(2) hydrogenation to methanol.Results indicate that the flower-like Ru/In_(2)O_(3)(Ru/In_(2)O_(3)-F)exhibits higher catalytic performance than Ru/In_(2)O_(3) with other morphologies,achieving a 12.9%CO_(2) conversion,74.02%methanol selectivity,and 671.36 mg_(MeOH) h^(−1) g_(cat)^(−1) methanol spatiotemporal yield.Furthermore,Ru/In_(2)O_(3)-F maintains its catalytic stability over 200 h at 5 MPa and 290℃.The promotional effect mainly stems from the fact that electronic structure of Ru can be effectively adjusted by modulating the morphology of In_(2)O_(3).The strong interaction between atomically dispersed Ru and In_(2)O_(3)-F enhances the structural stability of Ru,inhibiting the agglomeration of the catalyst during the reaction process.Furthermore,density-functional theory calculations reveal that highly dispersed Ru atoms not only perform efficient and rapid electronic gain and loss processes,facilitating the catalytic activation of H_(2) into H intermediates.It also enables the generated reactive H to rapidly overflow to the surrounding In sites to participate in CO_(2) reduction.These findings provide a theoretical basis for the development of high-performance catalysts for CO_(2) hydrogenation.
基金the National Natural Science Foundation of China(52225606,52488201)the"Fundamental Research Funds for the Central Universities".
文摘Efficient CO_(2)photoreduction to produce fuel remains a great challenge,due to the fast recombination of photogenerated charge carriers and the lack of effective reactive sites in the developed photocatalysts.Herein,single Co atoms(Co_(SA))were highly dispersed on hydrothermally synthesized BiOCl nanosheets(BOC)by a facile two-step electrostatic self-assembly and pyrolysis method.The obtained Co_(SA)-BOC could be performed for efficient CO_(2)photoreduction to stoichiometrically produce CO and O_(2)at the ratio of 2:1,with the CO evolution rate reaching 45.93 μmol g^(-1)h^(-1),~4 times that of the pristine BOC.This distinctly improved photocatalytic performance for Co_(SA)-BOC should benefit from the introduction of atomically dispersed Co–O_(4)coordination structures,which could accelerate the migration of photogenerated charge carriers to surface by creating an impurity energy level in the forbidden band,and act as the reactive sites to deliver the photogenerated electrons to activate CO_(2)molecules for CO production.This work provides a facile and reliable strategy to highly disperse single atoms on low-dimensional semiconductors for efficient CO_(2)photoreduction to selectively produce CO.
基金supported by the National Natural Science Foundation of China(22234005,21974070)the Natural Science Foundation of Jiangsu Province(BK20222015)。
文摘Atomically dispersed catalysts exhibit significant influence on facilitating the sluggish oxygen reduction reaction(ORR)kinetics with high atom economy,owing to remarkable attributes including nearly 100%atomic utilization and exceptional catalytic functionality.Furthermore,accurately controlling atomic physical properties including spin,charge,orbital,and lattice degrees of atomically dispersed catalysts can realize the optimized chemical properties including maximum atom utilization efficiency,homogenous active centers,and satisfactory catalytic performance,but remains elusive.Here,through physical and chemical insight,we review and systematically summarize the strategies to optimize atomically dispersed ORR catalysts including adjusting the atomic coordination environment,adjacent electronic orbital and site density,and the choice of dual-atom sites.Then the emphasis is on the fundamental understanding of the correlation between the physical property and the catalytic behavior for atomically dispersed catalysts.Finally,an overview of the existing challenges and prospects to illustrate the current obstacles and potential opportunities for the advancement of atomically dispersed catalysts in the realm of electrocatalytic reactions is offered.
基金The authors gratefully acknowledge the financial support of the Fundamental Research Funds for the Central Universities(CCNU20TS013)the National Natural Science Foundation of China(No.21503273)the Program of Introducing Talents of Discipline to Universities of China(111 program,B17019)and the Recruitment Program of Global Youth Experts of China.
文摘Although nanozymes have been widely developed,accurate design of highly active sites at the atomic level to mimic the electronic and geometrical structure of enzymes and the exploration of underlying mechanisms still face significant challenges.Herein,two functional groups with opposite electron modulation abilities(nitro and amino)were introduced into the metal–organic frameworks(MIL-101(Fe))to tune the atomically dispersed metal sites and thus regulate the enzymelike activity.Notably,the functionalization of nitro can enhance the peroxidase(POD)-like activity of MIL-101(Fe),while the amino is poles apart.Theoretical calculations demonstrate that the introduction of nitro can not only regulate the geometry of adsorbed intermediates but also improve the electronic structure of metal active sites.Benefiting from both geometric and electronic effects,the nitro-functionalized MIL-101(Fe)with a low reaction energy barrier for the HO*formation exhibits a superior POD-like activity.As a concept of the application,a nitro-functionalized MIL-101(Fe)-based biosensor was elaborately applied for the sensitive detection of acetylcholinesterase activity in the range of 0.2–50 mU mL−1 with a limit of detection of 0.14 mU mL−1.Moreover,the detection of organophosphorus pesticides was also achieved.This work not only opens up new prospects for the rational design of highly active nanozymes at the atomic scale but also enhances the performance of nanozyme-based biosensors.
基金This work is supported by the Natural Sciences and Engineering Research Council of Canada(NSERC)Centre Québéco is sur les Materiaux Fonctionnels(CQMF),Fonds de Recherche du Québec-Nature et Technologies(FRQNT)+2 种基金Institut National de la Recherche Scientifique(INRS)This work is also supported by the National Natural Science Foundation of China(21972017)the“Scientific and Technical Innovation Action Plan”Hong Kong,Macao and Taiwan Science&Technology Cooperation Project of Shanghai Science and Technology Committee(19160760600).F.Dong gratefully acknowledges scholarships from the China Scholarship Council(CSC).
文摘Rechargeable zinc-air batteries(ZABs)are currently receiving extensive attention because of their extremely high theoretical specific energy density,low manufacturing costs,and environmental friendliness.Exploring bifunctional catalysts with high activity and stability to overcome sluggish kinetics of oxygen reduction reaction and oxygen evolution reaction is critical for the development of rechargeable ZABs.Atomically dispersed metal-nitrogen-carbon(M-N-C)catalysts possessing prominent advantages of high metal atom utilization and electrocatalytic activity are promising candidates to promote oxygen electrocatalysis.In this work,general principles for designing atomically dispersed M-N-C are reviewed.Then,strategies aiming at enhancing the bifunctional catalytic activity and stability are presented.Finally,the challenges and perspectives of M-N-C bifunctional oxygen catalysts for ZABs are outlined.It is expected that this review will provide insights into the targeted optimization of atomically dispersed M-N-C catalysts in rechargeable ZABs.
文摘Heterogeneous catalysts with ultra-small clusters and atomically dispersed(USCAD)active sites have gained increasing attention in recent years.However,developing USCAD catalysts with high-density metal sites anchored in porous nanomaterials is still challenging.Here,through the template-free S-assisted pyrolysis of low-cost Fe-salts with melamine(MA),porous alveolate Fe/g-C3N4 catalysts with high-density(Fe loading up to 17.7 wt%)and increased USCAD Fe sites were synthesized.The presence of a certain amount of S species in the Fe-salts/MA system plays an important role in the formation of USCAD S-Fe-salt/CN catalysts;the S species act as a"sacrificial carrier"to increase the dispersion of Fe species through Fe-S coordination and generate porous alveolate structure by escaping in the form of SO2 during pyrolysis.The S-Fe-salt/CN catalysts exhibit greatly promoted activity and reusability for degrading various organic pollutants in advanced oxidation processes compared to the corresponding Fe-salt/CN catalysts,due to the promoted accessibility of USCAD Fe sites by the porous alveolate structure.This S-assisted method exhibits good feasibility in a large variety of S species(thiourea,S powder,and NH4SCN)and Fe salts,providing a new avenue for the low-cost and large-scale synthesis of high-density USCAD metal/g-C3N4 catalysts.
基金supported by the National Key Research and Development Program of China(2021YFA1500401)the National Natural Science Foundation of China(21890380,21975290,21901089,and 21821003)+1 种基金the Foundation of Basic and Applied Basic Research of Guangdong Province(2020B1515120024)C.-T.H.acknowledges the Jiangxi Province(20202ZDB01004 and jxsq2018106041).
文摘The real structure and in situ evolution of catalysts under working conditions are of paramount importance,especially for bifunctional electrocatalysis.Here,we report asymmetric structural evolution and dynamic hydrogen-bonding promotion mechanism of an atomically dispersed electrocatalyst.Pyrolysis of Co/Ni-doped MAF-4/ZIF-8 yielded nitrogen-doped porous carbons functionalized by atomically dispersed Co–Ni dual-metal sites with an unprecedented N8V4 structure,which can serve as an efficient bifunctional electrocatalyst for overall water splitting.More importantly,the electrocatalyst showed remarkable activation behavior due to the in situ oxidation of the carbon substrate to form C–OH groups.Density functional theory calculations suggested that the flexible C–OH groups can form reversible hydrogen bonds with the oxygen evolution reaction intermediates,giving a bridge between elementary reactions to break the conventional scaling relationship.
基金This work was financially supported by the Australian Research Council(ARC)Discovery Projects(DP210103266,DP200100965 and DP200100365)the ARC Discovery Early Career Researcher Award(DE210101102)the Griffith University Postdoctoral Fellowship Scheme(YUDOU 036 Research Internal).
文摘It is challenging to create cation vacancies in electrode materials for enhancing the performance of rechargeable lithium ion batteries (LIBs). Herein, we utilized a strong alkaline etching method to successfully create Co vacancies at the interface of atomically thin Co_(3−x)O_(4)/graphene@CNT heterostructure for high-energy/power lithium storage. The creation of Co-vacancies in the sample was confirmed by high-resolution scanning transmission electron microscope (HRSTEM), X-ray photoelectron spectroscopy (XPS) and electron energy loss near-edge structures (ELNES). The obtained Co_(3−x)O_(4)/graphene@CNT delivers an ultra-high capacity of 1688.2 mAh g^(−1) at 0.2 C, excellent rate capability of 83.7% capacity retention at 1 C, and an ultralong life up to 1500 cycles with a reversible capacity of 1066.3 mAh g^(−1). Reaction kinetic study suggests a significant contribution from pseudocapacitive storage induced by the Co-vacancies at the Co_(3−x)O_(4)/graphene@CNT interface. Density functional theory confirms that the Co-vacancies could dramatically enhance the Li adsorption and provide an additional pathway with a lower energy barrier for Li diffusion, which results in an intercalation pseudocapacitive behavior and high-capacity/rate energy storage.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11374092,61474040,61574054,and 61505051)the Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province,Chinathe Science and Technology Department of Hunan Province,China(Grant No.2014FJ2001)
文摘Atomically thin two-dimensional （2D） layered materials have potential applications in nanoelectronics, nanophoton- ics, and integrated optoelectronics. Band gap engineering of these 2D semiconductors is critical for their broad applications in high-performance integrated devices, such as broad-band photodetectors, multi-color light emitting diodes （LEDs）, and high-efficiency photovoltaic devices. In this review, we will summarize the recent progress on the controlled growth of composition modulated atomically thin 2D semiconductor alloys with band gaps tuned in a wide range, as well as their induced applications in broadly tunable optoelectronic components. The band gap engineered 2D semiconductors could open up an exciting opportunity for probing their fundamental physical properties in 2D systems and may find diverse applications in functional electronic/optoelectronic devices.
基金supported by the National Key Research and Development Program of China(2020YFA0715004)National Natural Science Foundation of China(51832004)+1 种基金Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(XHT2020-003)the Fundamental Research Funds for the Central Universities(195101005,2020-CL-A1-28,2020Ⅲ004GX).
文摘Metal silicate hydroxides have been recognized as efficient oxygen evolution reaction(OER)electrocatalysts,yet tailoring of their intrinsic activity remains confused.Herein,Fe had been incorporated into cobalt silicate hydroxide nanosheets and the resulted material achieves a competitive OER catalytic activity.It is found that the doping state obviously affects the electrical transport property.Specifically,highly dispersed Fe atoms(low-concentration Fe doping)trigger slight electron transfer to Co atoms while serried Fe(highconcentration Fe doping)attract vast electrons.By introducing 6 at.%Fe doping,partial relatively inert Co sites are activated by atomically dispersed Fe,bearing an optimal metal 3d electronic occupation and adsorption capacity to oxygen intermediate.The introduced Co-O-Fe unit trigger the p-donation effect and decrease the number of electrons in p*-antibonding orbitals,which enhance the Fe-O covalency and the structural stability.As a result,the sample delivers a low overpotential of 293 mV to achieve a current density of 10 mA cm^(-2).This work clarifies the superiority of atomically dispersed doping state,which is of fundamental interest to the design of doped catalyst.
文摘Oxygen reduction reaction(ORR)is the key reaction at the cathode of proton exchange membrane fuel cells(PEMFCs)and metal-air batteries(1)To address the challenges associated with Pt-based electrocatalysts having prominent activity for ORR,e.g.scarce abundance,prohibitive cost,poor stability,and vulnerability to reaction intermediates,it is necessary to explore other cost-effective ORR electrocatalysts with competitive or even superior performance to promote the commercialization of the energy conversion devices.
