Development of high-efficiency bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalysts is vital for the widespread application of zinc-air batteries(ZABs).However,it still remains...Development of high-efficiency bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalysts is vital for the widespread application of zinc-air batteries(ZABs).However,it still remains a great challenge to avoid the inhomogeneous distribution and aggregation of metal single-atomic active centers in the construction of bifunctional electrocatalysts with atomically dispersed multimetallic sites because of the common calcination method.Herein,we report a novel catalyst with phthalocyanine-assembled Fe-Co-Ni single-atomic triple sites dispersed on sulfur-doped graphene using a simple ultrasonic procedure without calcination,and X-ray absorption fine structure(XAFS),aberration-corrected scanning transmission electron microscopy(AC-STEM),and other detailed characterizations are performed to demonstrate the successful synthesis.The novel catalyst shows extraordinary bifunctional ORR/OER activities with a fairly low potential difference(ΔE=0.621 V)between the OER overpotential(Ej10=315 mV at 10 m A cm^(-2))and the ORR half-wave potential(Ehalf-wave=0.924 V).Moreover,the above catalyst shows excellent ZAB performance,with an outstanding specific capacity(786 mAh g^(-1)),noteworthy maximum power density(139 mW cm^(-2)),and extraordinary rechargeability(discharged and charged at 5 mA cm^(-2) for more than 1000 h).Theoretical calculations reveal the vital importance of the preferable synergetic coupling effect between adjacent active sites in the Fe-Co-Ni trimetallic single-atomic sites during the ORR/OER processes.This study provides a new avenue for the investigation of bifunctional electrocatalysts with atomically dispersed trimetallic sites,which is intended for enhancing the ORR/OER performance in ZABs.展开更多
The practical application of lithium–sulfur batteries(LSBs)is severely hindered by the undesirable shuttling of lithium polysulfides(LiPSs)and sluggish redox kinetics of sulfur species.Herein,a series of ultrathin si...The practical application of lithium–sulfur batteries(LSBs)is severely hindered by the undesirable shuttling of lithium polysulfides(LiPSs)and sluggish redox kinetics of sulfur species.Herein,a series of ultrathin singleatomic tungsten-doped Co_(3)O_(4)(Wx-Co_(3)O_(4))nanosheets as catalytic additives in the sulfur cathode for LSBs are rationally designed and synthesized.Benefiting from the enhanced catalytic activity and optimized electronic structure by W doping,the Wx-Co_(3)O_(4) not only reduces the shuttling of LiPSs but also decreases the energy barrier of sulfur redox reactions of sulfur species,leading to accelerated electrode kinetic.As a result,LSB cathodes with the use of 5.0 wt%W0.02-Co_(3)O_(4) as the electrocatalyst show the high reversible capacities of 1217.0 and 558.6 mAh g^(-1) at 0.2 and 5.0 C,respectively,and maintain a high reversible capacity of 644.6 mAh g^(-1) at 1.0 C(1.0 C=1675 mA g^(-1))after 500 cycles.With a high sulfur loading of 5.5 mg cm^(-2) and electrolyte–electrode ratio of 8μL_(electrolyte) mg_(sulfur)^(-1),the 5.0 wt%W_(0.02)-Co_(3)O_(4)-based sulfur cathode also retains a high reversible areal capacity of 3.86 mAh cm^(-2) at 0.1 C after 50 cycles with an initial capacity retention of 84.7%.展开更多
Fe-based single-atomic site catalysts(SASCs),with the natural metalloproteases-like active site structure,have attracted widespread attention in biocatalysis and biosensing.Precisely,controlling the isolated single-at...Fe-based single-atomic site catalysts(SASCs),with the natural metalloproteases-like active site structure,have attracted widespread attention in biocatalysis and biosensing.Precisely,controlling the isolated single-atom Fe-N-C active site structure is crucial to improve the SASCs’performance.In this work,we use a facile ion-imprinting method(IIM)to synthesize isolated Fe-N-C single-atomic site catalysts(IIM-Fe-SASC).With this method,the ion-imprinting process can precisely control ion at the atomic level and form numerous well-defined single-atomic Fe-N-C sites.The IIM-Fe-SASC shows better peroxidase-like activities than that of non-imprinted references.Due to its excellent properties,IIM-Fe-SASC is an ideal nanoprobe used in the colorimetric biosensing of hydrogen peroxide(H_(2)O_(2)).Using IIM-Fe-SASC as the nanoprobe,in situ detection of H_(2)O_(2)generated from MDA-MB-231 cells has been successfully demonstrated with satisfactory sensitivity and specificity.This work opens a novel and easy route in designing advanced SASC and provides a sensitive tool for intracellular H_(2)O_(2)detection.展开更多
Aqueous zinc-sulfur batteries at room temperature hold great potential for next-generation energy storage technology due to their low cost,safety and high energy density.However,slow reaction kinetics and high activat...Aqueous zinc-sulfur batteries at room temperature hold great potential for next-generation energy storage technology due to their low cost,safety and high energy density.However,slow reaction kinetics and high activation energy at the sulfur cathode pose great challenges for the practical applications.Herein,biomass-derived carbon with single-atomic cobalt sites(MMPC-Co)is synthesized as the cathode in Zn-S batteries.The catalysis of single-atom Co sites greatly promotes the transform of cathode electrolyte interface(CEI)on the cathode surface,while offering accelerated charge transfer rate for high conversion reversibility and large electrochemical surface area(ECSA)for high electrocatalytic current.Furthermore,the rich pore structure not only physically limits sulfur loss,but also accelerates the transport of zinc ions.In addition,the large pore volume of MMPC-Co is able to relieve the stress effect caused by the volume expansion of Zn S during charge/discharge cycles,thereby maintaining the stability of electrode structure.Consequently,the sulfur cathode maintains a high specific capacity of 729.96 m A h g^(-1)after 500 cycles at4 A g^(-1),which is much better than most cathode materials reported in the literature.This work provides new insights into the design and development of room-temperature aqueous Zn-S batteries.展开更多
Ammonia nitrogen (NH_(4)^(+)-N) is a ubiquitous environmental pollutant,especially in offshore aquaculture systems.Electrochemical oxidation is very promising to remove NH_(4)^(+)-N,but suffers from the use of preciou...Ammonia nitrogen (NH_(4)^(+)-N) is a ubiquitous environmental pollutant,especially in offshore aquaculture systems.Electrochemical oxidation is very promising to remove NH_(4)^(+)-N,but suffers from the use of precious metals anodes.In this work,a robust and cheap electrocatalyst,iron single-atoms distributed in nitrogen-doped carbon (Fe-SAs/N-C),was developed for electrochemical removal of NH_(4)^(+)-N from in wastewater containing chloride.The FeSAs/N-C catalyst exhibited superior activity than that of iron nanoparticles loaded carbon(Fe-NPs/N-C),unmodified carbon and conventional Ti/IrO_(2)-TiO_(2)-RuO_(2)electrodes.And high removal efficiency (>99%) could be achieved as well as high N_(2)selectivity (99.5%) at low current density.Further experiments and density functional theory (DFT) calculations demonstrated the indispensable role of single-atom iron in the promoted generation of chloride derived species for efficient removal of NH_(4)^(+)-N.This study provides promising inexpensive catalysts for NH_(4)^(+)-N removal in aquaculture wastewater.展开更多
Bandgap engineering through single-atom site binding on semiconducting photocatalyst can boost the intrinsic activity,selectivity,carrier separation,and electron transport.Here,we report a mixed-valence Ag(0)and Ag(I)...Bandgap engineering through single-atom site binding on semiconducting photocatalyst can boost the intrinsic activity,selectivity,carrier separation,and electron transport.Here,we report a mixed-valence Ag(0)and Ag(I)single atoms co-decorated semiconducting chalcopyrite quantum dots(Ag/CuFeS_(2)QDs)photocatalyst.It demonstrates efficient photocatalytic performances for specific organic dye(rhodamine B,denoted as RhB)as well as inorganic dye(Cr(VI))removal in water under natural sunlight irradiation.The RhB degradation and Cr(VI)removal efficiencies by Ag/CuFeS_(2)QDs were 3.55 and 6.75 times higher than those of the naked CuFeS_(2)QDs at their optimal pH conditions,respectively.Besides,in a mixture of RhB and Cr(VI)solution under neutral condition,the removal ratio has been elevated from 30.2%to 79.4%for Cr(VI),and from 95.2%to 97.3%for RhB degradation by using Ag/CuFeS_(2)QDs after 2 h sunlight illumination.The intrinsic mechanism for the photocatalytic performance improvement is attributed to the narrow bandgap of the single-atomic Ag(I)anchored CuFeS_(2)QDs,which engineers the electronic structure as well as expands the optical light response range.Significantly,the highly active Ag(0)/CuFeS_(2)and Ag(I)/CuFeS_(2)effectively improve the separation efficiency of the carriers,thus enhancing the photocatalytic performances.This work presents a highly efficient single atom/QDs photocatalyst,constructed through bandgap engineering via mixed-valence single noble metal atoms binding on semiconducting QDs.It paves the way for developing high-efficiency single-atom photocatalysts for complex pollutions removal in dyeing wastewater environment.展开更多
Lithium-sulfur(Li-S) batteries have attracted considerable attention as one of the most appealing energy storage systems.Strenuous efforts have been devoted to tackling the tremendous challenges,mainly pertaining to t...Lithium-sulfur(Li-S) batteries have attracted considerable attention as one of the most appealing energy storage systems.Strenuous efforts have been devoted to tackling the tremendous challenges,mainly pertaining to the severe shuttle effect,sluggish redox kinetics and lithium dendritic growth.Single-atomic mediators as promising candidates exhibit impressive performance in addressing these intractable issues.Related research often utilizes a trial-and-error approach,proposing solutions to fabricate single-atomic materials with diversified features.However,comprehensive review articles especially targeting demand-driven preparation are still in a nascent stage.Inspired by these considerations,this review summarizes the design of single-atomic mediators based on the application case-studies in LiS batteries and other metal-sulfur systems.Emerging preparation routes represented by chemical vapor deposition technology are introduced in a demand-oriented classification.Finally,future research directions are proposed to foster the advancement of single-atomic mediators in Li-S realm.展开更多
Oxygen reduction reaction(ORR)is crucial for Znair batteries,while also serves as a core electrochemical process in oxygen depolarized cathodes(ODCs)for chlor-alkali electrolysis.The lack of cost-effective,highly acti...Oxygen reduction reaction(ORR)is crucial for Znair batteries,while also serves as a core electrochemical process in oxygen depolarized cathodes(ODCs)for chlor-alkali electrolysis.The lack of cost-effective,highly active ORR electrocatalysts with superior kinetics hinders progress in this field.Herein,we report the Fe/Ni dual single-atomic sites anchored by commercial carbon black(Fe/Ni-N/CB)using rigid ligand confined and high-temperature shock(HTS)strategy in less than 0.5 s.Theoretical calculation reveals that singleatomic Fe is the real active site.Single-atomic Fe and Ni species in Fe/Ni-N/CB synergistically accelerate the kinetics of ORR by reducing the energy barrier of the rate-determining step.A large half-wave potential(E_(1/2))of 0.907 V is achieved in 0.1 M KOH aqueous solution.The assembled aqueous Zn-air battery(A-ZAB)with Fe/Ni-N/CB cathode presents remarkable charge-discharge cycling stability for over 650 h without voltage gap degradation.The quasi-solid-state Zn-air battery(QSS-ZAB)exhibits excellent reversibility over a 150-h operation at 0.5 mA·cm^(-2) with negligible energy conversion efficiency recession.Impressively,Fe/Ni-N/CB||RuO_(2)chloralkali flow cell exhibits a low cell voltage of 1.60 V at a large current density of 300 mA·cm^(-2) at 80℃,and demonstrates exceptional durability with 7% current density decay over 150 h of continuous operation at 100 mA·cm^(-2).Fe/Ni-N/CB||RuO_(2)achieves near-ideal caustic current efficiency(~97.2%)at the current density of 300 mA·cm^(-2).This work provides a rapid and economical synthesis technique for the synthesis of catalysts at the atomic scale while demonstrating significant potential for application in energy-saving chlor-alkali electrolyzer.展开更多
Electrocatalytic nitrate reduction reaction(NO_(3)RR)to ammonia provides a promising approach to environmental preservation and sustainable energy production,but suffers from a low yield rate and poor Faradic efficien...Electrocatalytic nitrate reduction reaction(NO_(3)RR)to ammonia provides a promising approach to environmental preservation and sustainable energy production,but suffers from a low yield rate and poor Faradic efficiency,ascribed to the sluggish active hydrogen(H^(*))generation via water dissociation.Herein,single Ru atoms anchored Co(OH)_(2)(Ru1/Co(OH)_(2))catalysts are synthesized for selective nitrate reduction to ammonia,which exhibits an excellent NH_(3)yield rate of 4200μg h^(-1)cm^(-2)and a high NH_(3)Faradic efficiency of 97%at-0.33 V versus reversible hydrogen electrode,outperforming the counterpart Co(OH)_(2)and the mostly reported electrocatalysts.Experimental and theoretical results reveal that the addition of Ru atoms can boost H^(*)generation and decrease the hydrogenation energy barrier on Ru1/Co(OH)_(2),leading to enhanced NO_(3)RR performance.An integrated system of electrochemical NO_(3)RR electrolyzer and in-situ NH_(3)recovery is present,where the electrochemical NO_(3)RR can be coupled with a hydrazine oxidation reaction to achieve a more highly efficient and electricity-saving system for NH_(3)recovery.This work provides guidance for the rational design of high-performance NO_(3)RR electrocatalysts by the effective regulation of H^(*)generation and holds great promise for simultaneous nitrate-containing wastewater treatment and resource recovery.展开更多
Electrocatalytic denitrification(ECDN)offers a sustainable prospect by enabling efficient NO_(3) conversion to harmless N_(2).However,the N_(2)-selective ECDN remains challenging due to the sluggish kinetics of N–N c...Electrocatalytic denitrification(ECDN)offers a sustainable prospect by enabling efficient NO_(3) conversion to harmless N_(2).However,the N_(2)-selective ECDN remains challenging due to the sluggish kinetics of N–N coupling during NO_(3) reduction.Here,we developed a novel electrocatalyst of dual single-atomic sites on double-shelled mesoporous carbon spheres(FeNC@MgNC-DMCS)using a continuous sequential modular assembly and pyrol-ysis approach.The outer Mg–N_(4) shell creates medium basicity sites that function as the proton fence,which optimizes the spatial distribution of H^(*)species and suppresses^(*)N protonation pathways that would otherwise lead to ammonia formation.Concurrently,the inner Fe–N_(4) shell promotes N–N coupling for N_(2) production.92.8%NO_(3)^(-) removal and 95.2%N_(2) selectivity was achieved by the optimized FeNC@MgNC-DMCS catalyst.Furthermore,long-term flow cell testing demonstrated remarkable durability,highlighting the practical potential of FeNC@MgNC-DMCS for sustainable wastewater treatment applications.This work introduces a catalyst design paradigm that integrates a proton-repelling interface to decouple H^(*)availability from N_(2) formation pathways,thereby enabling the development of high-performance ECDN catalysts with balanced activity and selectivity for environmental remediation applications.展开更多
The rational design of efficient single-atomic(SA)catalysts is essential and highly desirable but impeded by the lack of sufficient acknowledge between structure and property.To this end,it is critical to clarify the ...The rational design of efficient single-atomic(SA)catalysts is essential and highly desirable but impeded by the lack of sufficient acknowledge between structure and property.To this end,it is critical to clarify the effect of the coordination structure of active metal centers on the catalytic activities for the design of such catalysts.Here,we report that different coordination structures of SA Pt catalysts can dramatically influence their activities for anti-Markovnikov hydroboration of alkenes.Compared with the other two coordination structures(Pt-N4 and Pt-O2),the SA Pt species coordinated with three O atoms(Pt-O3)display the highest turnover number value of 3288 for the hydroboration reaction to access the important alkylboronic esters.Density functional theory calculations reveal that a superior catalytic activity can be expected for alkene hydroboration over the three O coordinated Pt species due to the lowest reaction energy(ΔG)limiting step from the reaction phase diagram.展开更多
Anodic urea oxidation reaction(UOR)is an intriguing half reaction that can replace oxygen evolution reaction(OER)and work together with hydrogen evolution reaction(HER)toward simultaneous hydrogen fuel generation and ...Anodic urea oxidation reaction(UOR)is an intriguing half reaction that can replace oxygen evolution reaction(OER)and work together with hydrogen evolution reaction(HER)toward simultaneous hydrogen fuel generation and urea-rich wastewater purification;however,it remains a challenge to achieve overall urea electrolysis with high efficiency.Herein,we report a multifunctional electrocatalyst termed as Rh/Ni V-LDH,through integration of nickel-vanadium layered double hydroxide(LDH)with rhodium single-atom catalyst(SAC),to achieve this goal.The electrocatalyst delivers high HER mass activity of0.262 A mg^(-1) and exceptionally high turnover frequency(TOF)of 2.125 s^(-1) at an overpotential of100 m V.Moreover,exceptional activity toward urea oxidation is addressed,which requires a potential of 1.33 V to yield 10 mA cm^(-2),endorsing the potential to surmount the sluggish OER.The splendid catalytic activity is enabled by the synergy of the Ni V-LDH support and the atomically dispersed Rh sites(located on the Ni-V hollow sites)as evidenced both experimentally and theoretically.The selfsupported Rh/Ni V-LDH catalyst serving as the anode and cathode for overall urea electrolysis(1 mol L^(-1) KOH with 0.33 mol L^(-1) urea as electrolyte)only requires a small voltage of 1.47 V to deliver 100 mA cm^(-2) with excellent stability.This work provides important insights into multifunctional SAC design from the perspective of support sites toward overall electrolysis applications.展开更多
Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)is considered an efficient way to convert CO_(2)into high-value-added chemicals,and thus is of significant social and economic value.Metal single-atomic site catalyst...Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)is considered an efficient way to convert CO_(2)into high-value-added chemicals,and thus is of significant social and economic value.Metal single-atomic site catalysts(SASCs)generally have excellent selectivity because of their 100%atomic utilization and uniform structure of active sites,and thus promise a broad range of applications.However,SASCs still face challenges such as low intrinsic activity and low density of active sites.Precise regulation of the microstructures of SASCs is an effective method to improve their CO_(2)RR performance and to obtain deep reduction products.In this article,we systematically summarize the current research status of SASCs developed for highly efficient catalysis of CO_(2)RR,discuss the various structural regulation methods for enhanced activity and selectivity of SASCs for CO_(2)RR,and review the application of in-situ characterization technologies in the SASC-catalyzed CO_(2)RR.We then discuss the problems yet to be solved in this area,and propose the future directions of the research on the design and application of SASCs for CO_(2)RR.展开更多
Dual-metal single-atom catalysts(DACs),featuring high atomic utilization efficiency,excellent selectivity,and stability originating from the atomically dispersed nature,have emerged as a new frontier in heterogeneous ...Dual-metal single-atom catalysts(DACs),featuring high atomic utilization efficiency,excellent selectivity,and stability originating from the atomically dispersed nature,have emerged as a new frontier in heterogeneous electrocatalysis due to the synergistic effect between diversified metal active sites in promoting their catalytic activity.In this review,the recent progress and development on the syntheses,characterizations,theoretical uniqueness,and applications for various catalytic reactions and devices(oxygen reduction reaction,oxygen evolution reaction,hydrogen evolution reaction,CO_(2) reduction reaction,N2 reduction reaction,proton exchange membrane fuel cells)are summarized and reviewed.Specifically,the synergistic effect between the two metal centers and electronic structures of catalysts is systematically discussed.Moreover,the future challenges and prospects in developing practical DACs are proposed as a possible direction for further investigation.展开更多
Single-atom catalysts(SACs)with high catalytic activity as well as great stability are demonstrating great promotion in electrocatalytic energy conversion,which is also a big challenge to achieve.Herein,we proposed a ...Single-atom catalysts(SACs)with high catalytic activity as well as great stability are demonstrating great promotion in electrocatalytic energy conversion,which is also a big challenge to achieve.Herein,we proposed a facile synthetic strategy to construct nickel-iron bimetallic hydroxide nanoribbon stabilized single-atom iridium catalysts(Ir-NiFe-OH),where the nickel-iron hydroxide nanoribbon not only can serve as good electronic conductor,but also can well stabilize and fully expose single-atom sites.Adopted as catalyst for urea oxidation reaction(UOR),it exhibited excellent UOR performance that it only needed a low operated potential of 1.38 V to achieve the current density of 100 mA·cm^(-2).In-situ Fourier transform infrared spectroscopy,X-ray absorption spectrum,and density functional theory calculations proved that Ir species are active centers and the existence of both Ni and Fe in the local structure of Ir atom can optimize the d-band center of Ir species,promoting the adsorption of intermediates and desorption of products for UOR.The hydrogen evolution reaction(HER)/UOR electrocatalytic cell demanded voltages of 1.46 and 1.50 V to achieve 50 and 100 mA·cm^(-2),respectively,which demonstrated a higher activity and better stability than those of conventional catalysts.This work opens a new avenue to develop catalysts for UORs with boosted activity and stability.展开更多
The use of single-atom cocatalysts plays a crucial role in enhancing artificial photocatalysis,where the precise construction of stable and efficient single-atom configuration is essential but remains challenging.Here...The use of single-atom cocatalysts plays a crucial role in enhancing artificial photocatalysis,where the precise construction of stable and efficient single-atom configuration is essential but remains challenging.Here,we report a simple one-step hydrothermal method for preparing single-atomic Mo modified ZnIn_(2)S_(4)(Mo-ZIS)nanosheets as a highly active photocatalytic hydrogen evolution(PHE)photocatalyst.The Mo substituting for portion of In atoms in ZIS nanosheets induces the spatial charge redistribution,which not only promotes the separation of photogenerated charge carriers but also optimizes the Gibbs free energy of adsorbing H*on S atoms at basal planes.As a result,Mo-ZIS exhibits an impressive PHE rate as high as 6.71 mmol·g^(−1)·h^(−1),over 10 times that of the pristine ZIS,with an apparent quantum efficiency(AQE)up to 38.8%at 420 nm.This study gains insights into the coordination configuration and electronic modulation resulting from single-atomic decoration,providing mechanistic cognitions for the development of advanced photocatalysts via non-precious metal atomic modification.展开更多
Solving the problems of carbon dioxide(CO_(2))emissions and energy scarcity by the development of highly selective,cost-effective,and reliable catalysts for the electrochemical reduction of CO_(2)to useful carbon-base...Solving the problems of carbon dioxide(CO_(2))emissions and energy scarcity by the development of highly selective,cost-effective,and reliable catalysts for the electrochemical reduction of CO_(2)to useful carbon-based products would be very helpful.We report the synthesis of an efficient graphene-supported bismuth single-atom catalyst(BiSA-G)featuring a BiN_(4)coordination structure for this purpose.The synthesis used tannic acid as a multifunctional ligand and ammonia as a nitrogen dopant.Using a scalable coordination chemistry approach,BiN_(4)sites were uniformly dispersed on the graphene substrate and were found to have an outstanding ability for the conversion of CO_(2)to CO,with a high Faradaic efficiency of 97.4%at−0.55 V(vs.RHE)and a high turnover frequency of 5230 h^(−1)along with outstanding stability.Density functional theory calculations confirmed that the BiN_(4)site serves as the dominant active center,simultaneously facilitating CO_(2)activation and the efficient formation of the crucial intermediate*COOH with a reduced free energy barrier.This discovery offers a new way for the atomic-scale design of high-efficiency catalysts for the electrochemical CO_(2)reduction reaction,potentially helping sustainable carbon use.展开更多
In recent years,numer-ous single-atom catalysts(SACs)have been synthesized to activate persulfate(PS)by a non-radical pathway because of its high se-lectivity,and activity for the cata-lyst.Metal-nitrogen-carbon(M-N_(...In recent years,numer-ous single-atom catalysts(SACs)have been synthesized to activate persulfate(PS)by a non-radical pathway because of its high se-lectivity,and activity for the cata-lyst.Metal-nitrogen-carbon(M-N_(x)-C)has been identified as the key active site in SACs.Although methods for preparing SACs have been extensively reported,a systematic summary of the direct construction of M-N_(x)-C,espe-cially unconventional metal-nitrogen-carbon(UM-N_(x)-C,x≠4),on SACs for PS non-radical activation has still not been reported.The role of the M-N_(x)-C active sites on PS non-radical activation is discussed and methods for the formation of M-N_(x)-C and UM-N_(x)-C active sites in SACs and the effect of catalyst carriers such as carbon nitride(g-C_(3)N_(4)),MOFs,COFs,and other car-bon materials are reviewed.Direct and indirect methods,especially for UM-N_(x)-C active site formation,are also elaborated.Factors affecting the formation of a M-N_(x)-C active site on SACs are also discussed.Prospects for the use of M-N_(x)-C active sites for the non-radical activation of PS by SACs to remove organic contaminants from wastewater are evaluated.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 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
基金financially supported by the National Natural Science Foundation of China(Grant Nos.22305071,52472200,52271176,and52072114)the 111 Project(Grant No.D17007)+3 种基金Henan Center for Outstanding Overseas Scientists(Grant No.GZS2022017)the China Postdoctoral Science Foundation(Grant No.2022M721049)the Henan Province Key Research and Development Project(Grant No.231111520500)the Natural Science Foundation of Henan Province(Grant No.252300421556)。
文摘Development of high-efficiency bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalysts is vital for the widespread application of zinc-air batteries(ZABs).However,it still remains a great challenge to avoid the inhomogeneous distribution and aggregation of metal single-atomic active centers in the construction of bifunctional electrocatalysts with atomically dispersed multimetallic sites because of the common calcination method.Herein,we report a novel catalyst with phthalocyanine-assembled Fe-Co-Ni single-atomic triple sites dispersed on sulfur-doped graphene using a simple ultrasonic procedure without calcination,and X-ray absorption fine structure(XAFS),aberration-corrected scanning transmission electron microscopy(AC-STEM),and other detailed characterizations are performed to demonstrate the successful synthesis.The novel catalyst shows extraordinary bifunctional ORR/OER activities with a fairly low potential difference(ΔE=0.621 V)between the OER overpotential(Ej10=315 mV at 10 m A cm^(-2))and the ORR half-wave potential(Ehalf-wave=0.924 V).Moreover,the above catalyst shows excellent ZAB performance,with an outstanding specific capacity(786 mAh g^(-1)),noteworthy maximum power density(139 mW cm^(-2)),and extraordinary rechargeability(discharged and charged at 5 mA cm^(-2) for more than 1000 h).Theoretical calculations reveal the vital importance of the preferable synergetic coupling effect between adjacent active sites in the Fe-Co-Ni trimetallic single-atomic sites during the ORR/OER processes.This study provides a new avenue for the investigation of bifunctional electrocatalysts with atomically dispersed trimetallic sites,which is intended for enhancing the ORR/OER performance in ZABs.
基金Shandong Excellent Young Scientists Fund Program(Oversea),Grant/Award Number:2022S02002Jinan“5150”Talent Program,Grant/Award Number:2022C01001+1 种基金Pearl River Talent Recruitment Program,Grant/Award Number:2019QN01L096Guangdong Innovative and Entrepreneurial Research Team Program,Grant/Award Number:2019ZT08L075。
文摘The practical application of lithium–sulfur batteries(LSBs)is severely hindered by the undesirable shuttling of lithium polysulfides(LiPSs)and sluggish redox kinetics of sulfur species.Herein,a series of ultrathin singleatomic tungsten-doped Co_(3)O_(4)(Wx-Co_(3)O_(4))nanosheets as catalytic additives in the sulfur cathode for LSBs are rationally designed and synthesized.Benefiting from the enhanced catalytic activity and optimized electronic structure by W doping,the Wx-Co_(3)O_(4) not only reduces the shuttling of LiPSs but also decreases the energy barrier of sulfur redox reactions of sulfur species,leading to accelerated electrode kinetic.As a result,LSB cathodes with the use of 5.0 wt%W0.02-Co_(3)O_(4) as the electrocatalyst show the high reversible capacities of 1217.0 and 558.6 mAh g^(-1) at 0.2 and 5.0 C,respectively,and maintain a high reversible capacity of 644.6 mAh g^(-1) at 1.0 C(1.0 C=1675 mA g^(-1))after 500 cycles.With a high sulfur loading of 5.5 mg cm^(-2) and electrolyte–electrode ratio of 8μL_(electrolyte) mg_(sulfur)^(-1),the 5.0 wt%W_(0.02)-Co_(3)O_(4)-based sulfur cathode also retains a high reversible areal capacity of 3.86 mAh cm^(-2) at 0.1 C after 50 cycles with an initial capacity retention of 84.7%.
基金This work was supported by a WSU startup fund.XAS measurements were done at beamline 12-BM of the Advanced Photon Source(APS),which is a User Facility operated for the U.S.Department of Energy Office of Science by Argonne National Laboratory under Contract DE-AC02-06CH11357.
文摘Fe-based single-atomic site catalysts(SASCs),with the natural metalloproteases-like active site structure,have attracted widespread attention in biocatalysis and biosensing.Precisely,controlling the isolated single-atom Fe-N-C active site structure is crucial to improve the SASCs’performance.In this work,we use a facile ion-imprinting method(IIM)to synthesize isolated Fe-N-C single-atomic site catalysts(IIM-Fe-SASC).With this method,the ion-imprinting process can precisely control ion at the atomic level and form numerous well-defined single-atomic Fe-N-C sites.The IIM-Fe-SASC shows better peroxidase-like activities than that of non-imprinted references.Due to its excellent properties,IIM-Fe-SASC is an ideal nanoprobe used in the colorimetric biosensing of hydrogen peroxide(H_(2)O_(2)).Using IIM-Fe-SASC as the nanoprobe,in situ detection of H_(2)O_(2)generated from MDA-MB-231 cells has been successfully demonstrated with satisfactory sensitivity and specificity.This work opens a novel and easy route in designing advanced SASC and provides a sensitive tool for intracellular H_(2)O_(2)detection.
基金the financial support from the National Natural Science Foundation of China,China(No.52172058)。
文摘Aqueous zinc-sulfur batteries at room temperature hold great potential for next-generation energy storage technology due to their low cost,safety and high energy density.However,slow reaction kinetics and high activation energy at the sulfur cathode pose great challenges for the practical applications.Herein,biomass-derived carbon with single-atomic cobalt sites(MMPC-Co)is synthesized as the cathode in Zn-S batteries.The catalysis of single-atom Co sites greatly promotes the transform of cathode electrolyte interface(CEI)on the cathode surface,while offering accelerated charge transfer rate for high conversion reversibility and large electrochemical surface area(ECSA)for high electrocatalytic current.Furthermore,the rich pore structure not only physically limits sulfur loss,but also accelerates the transport of zinc ions.In addition,the large pore volume of MMPC-Co is able to relieve the stress effect caused by the volume expansion of Zn S during charge/discharge cycles,thereby maintaining the stability of electrode structure.Consequently,the sulfur cathode maintains a high specific capacity of 729.96 m A h g^(-1)after 500 cycles at4 A g^(-1),which is much better than most cathode materials reported in the literature.This work provides new insights into the design and development of room-temperature aqueous Zn-S batteries.
基金supported by the Natural Science Foundation of Hubei Province of China(No. 2020CFB382)the National Natural Science Foundation of China(No. 22176068)the Research and Innovation Initiatives of WHPU(No. 2022J03)。
文摘Ammonia nitrogen (NH_(4)^(+)-N) is a ubiquitous environmental pollutant,especially in offshore aquaculture systems.Electrochemical oxidation is very promising to remove NH_(4)^(+)-N,but suffers from the use of precious metals anodes.In this work,a robust and cheap electrocatalyst,iron single-atoms distributed in nitrogen-doped carbon (Fe-SAs/N-C),was developed for electrochemical removal of NH_(4)^(+)-N from in wastewater containing chloride.The FeSAs/N-C catalyst exhibited superior activity than that of iron nanoparticles loaded carbon(Fe-NPs/N-C),unmodified carbon and conventional Ti/IrO_(2)-TiO_(2)-RuO_(2)electrodes.And high removal efficiency (>99%) could be achieved as well as high N_(2)selectivity (99.5%) at low current density.Further experiments and density functional theory (DFT) calculations demonstrated the indispensable role of single-atom iron in the promoted generation of chloride derived species for efficient removal of NH_(4)^(+)-N.This study provides promising inexpensive catalysts for NH_(4)^(+)-N removal in aquaculture wastewater.
基金financially supported by the National Natural Science Foundation of China(Nos.21777045,61875119)Distinguished Young Scholar Fund from Natural Science Funds of Guangdong Province,China(No.2020B151502094)+1 种基金the program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning,Shanghai Rising-Star Program(No.19QA1404000)Shanghai Talent Development Fund.
文摘Bandgap engineering through single-atom site binding on semiconducting photocatalyst can boost the intrinsic activity,selectivity,carrier separation,and electron transport.Here,we report a mixed-valence Ag(0)and Ag(I)single atoms co-decorated semiconducting chalcopyrite quantum dots(Ag/CuFeS_(2)QDs)photocatalyst.It demonstrates efficient photocatalytic performances for specific organic dye(rhodamine B,denoted as RhB)as well as inorganic dye(Cr(VI))removal in water under natural sunlight irradiation.The RhB degradation and Cr(VI)removal efficiencies by Ag/CuFeS_(2)QDs were 3.55 and 6.75 times higher than those of the naked CuFeS_(2)QDs at their optimal pH conditions,respectively.Besides,in a mixture of RhB and Cr(VI)solution under neutral condition,the removal ratio has been elevated from 30.2%to 79.4%for Cr(VI),and from 95.2%to 97.3%for RhB degradation by using Ag/CuFeS_(2)QDs after 2 h sunlight illumination.The intrinsic mechanism for the photocatalytic performance improvement is attributed to the narrow bandgap of the single-atomic Ag(I)anchored CuFeS_(2)QDs,which engineers the electronic structure as well as expands the optical light response range.Significantly,the highly active Ag(0)/CuFeS_(2)and Ag(I)/CuFeS_(2)effectively improve the separation efficiency of the carriers,thus enhancing the photocatalytic performances.This work presents a highly efficient single atom/QDs photocatalyst,constructed through bandgap engineering via mixed-valence single noble metal atoms binding on semiconducting QDs.It paves the way for developing high-efficiency single-atom photocatalysts for complex pollutions removal in dyeing wastewater environment.
基金supported by the National Natural Science Foundation of China(22179089)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX23_3245)support from Suzhou Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies,Suzhou,China。
文摘Lithium-sulfur(Li-S) batteries have attracted considerable attention as one of the most appealing energy storage systems.Strenuous efforts have been devoted to tackling the tremendous challenges,mainly pertaining to the severe shuttle effect,sluggish redox kinetics and lithium dendritic growth.Single-atomic mediators as promising candidates exhibit impressive performance in addressing these intractable issues.Related research often utilizes a trial-and-error approach,proposing solutions to fabricate single-atomic materials with diversified features.However,comprehensive review articles especially targeting demand-driven preparation are still in a nascent stage.Inspired by these considerations,this review summarizes the design of single-atomic mediators based on the application case-studies in LiS batteries and other metal-sulfur systems.Emerging preparation routes represented by chemical vapor deposition technology are introduced in a demand-oriented classification.Finally,future research directions are proposed to foster the advancement of single-atomic mediators in Li-S realm.
基金supported financially by the National Natural Science Foundation of China(No.52172208)Taishan Scholar Young Talent Program(No.tsqn202306216)Shandong Excellent Young Scientists Fund Program(Overseas,2023HWYQ‑091).
文摘Oxygen reduction reaction(ORR)is crucial for Znair batteries,while also serves as a core electrochemical process in oxygen depolarized cathodes(ODCs)for chlor-alkali electrolysis.The lack of cost-effective,highly active ORR electrocatalysts with superior kinetics hinders progress in this field.Herein,we report the Fe/Ni dual single-atomic sites anchored by commercial carbon black(Fe/Ni-N/CB)using rigid ligand confined and high-temperature shock(HTS)strategy in less than 0.5 s.Theoretical calculation reveals that singleatomic Fe is the real active site.Single-atomic Fe and Ni species in Fe/Ni-N/CB synergistically accelerate the kinetics of ORR by reducing the energy barrier of the rate-determining step.A large half-wave potential(E_(1/2))of 0.907 V is achieved in 0.1 M KOH aqueous solution.The assembled aqueous Zn-air battery(A-ZAB)with Fe/Ni-N/CB cathode presents remarkable charge-discharge cycling stability for over 650 h without voltage gap degradation.The quasi-solid-state Zn-air battery(QSS-ZAB)exhibits excellent reversibility over a 150-h operation at 0.5 mA·cm^(-2) with negligible energy conversion efficiency recession.Impressively,Fe/Ni-N/CB||RuO_(2)chloralkali flow cell exhibits a low cell voltage of 1.60 V at a large current density of 300 mA·cm^(-2) at 80℃,and demonstrates exceptional durability with 7% current density decay over 150 h of continuous operation at 100 mA·cm^(-2).Fe/Ni-N/CB||RuO_(2)achieves near-ideal caustic current efficiency(~97.2%)at the current density of 300 mA·cm^(-2).This work provides a rapid and economical synthesis technique for the synthesis of catalysts at the atomic scale while demonstrating significant potential for application in energy-saving chlor-alkali electrolyzer.
基金supported by the National Natural Science Foundation of China(grant nos.22206054,U21A20286,and 22478310)the Fundamental Research Funds for the Central China Normal University.
文摘Electrocatalytic nitrate reduction reaction(NO_(3)RR)to ammonia provides a promising approach to environmental preservation and sustainable energy production,but suffers from a low yield rate and poor Faradic efficiency,ascribed to the sluggish active hydrogen(H^(*))generation via water dissociation.Herein,single Ru atoms anchored Co(OH)_(2)(Ru1/Co(OH)_(2))catalysts are synthesized for selective nitrate reduction to ammonia,which exhibits an excellent NH_(3)yield rate of 4200μg h^(-1)cm^(-2)and a high NH_(3)Faradic efficiency of 97%at-0.33 V versus reversible hydrogen electrode,outperforming the counterpart Co(OH)_(2)and the mostly reported electrocatalysts.Experimental and theoretical results reveal that the addition of Ru atoms can boost H^(*)generation and decrease the hydrogenation energy barrier on Ru1/Co(OH)_(2),leading to enhanced NO_(3)RR performance.An integrated system of electrochemical NO_(3)RR electrolyzer and in-situ NH_(3)recovery is present,where the electrochemical NO_(3)RR can be coupled with a hydrazine oxidation reaction to achieve a more highly efficient and electricity-saving system for NH_(3)recovery.This work provides guidance for the rational design of high-performance NO_(3)RR electrocatalysts by the effective regulation of H^(*)generation and holds great promise for simultaneous nitrate-containing wastewater treatment and resource recovery.
基金Project supported by the National Natural Science Foundation of China(No.52200055).
文摘Electrocatalytic denitrification(ECDN)offers a sustainable prospect by enabling efficient NO_(3) conversion to harmless N_(2).However,the N_(2)-selective ECDN remains challenging due to the sluggish kinetics of N–N coupling during NO_(3) reduction.Here,we developed a novel electrocatalyst of dual single-atomic sites on double-shelled mesoporous carbon spheres(FeNC@MgNC-DMCS)using a continuous sequential modular assembly and pyrol-ysis approach.The outer Mg–N_(4) shell creates medium basicity sites that function as the proton fence,which optimizes the spatial distribution of H^(*)species and suppresses^(*)N protonation pathways that would otherwise lead to ammonia formation.Concurrently,the inner Fe–N_(4) shell promotes N–N coupling for N_(2) production.92.8%NO_(3)^(-) removal and 95.2%N_(2) selectivity was achieved by the optimized FeNC@MgNC-DMCS catalyst.Furthermore,long-term flow cell testing demonstrated remarkable durability,highlighting the practical potential of FeNC@MgNC-DMCS for sustainable wastewater treatment applications.This work introduces a catalyst design paradigm that integrates a proton-repelling interface to decouple H^(*)availability from N_(2) formation pathways,thereby enabling the development of high-performance ECDN catalysts with balanced activity and selectivity for environmental remediation applications.
基金This work was supported by the National Key R&D Program of China(2018YFA0702003)the National Natural Science Foundation of China(21890383,21671117,21871159 and 21901135).
文摘The rational design of efficient single-atomic(SA)catalysts is essential and highly desirable but impeded by the lack of sufficient acknowledge between structure and property.To this end,it is critical to clarify the effect of the coordination structure of active metal centers on the catalytic activities for the design of such catalysts.Here,we report that different coordination structures of SA Pt catalysts can dramatically influence their activities for anti-Markovnikov hydroboration of alkenes.Compared with the other two coordination structures(Pt-N4 and Pt-O2),the SA Pt species coordinated with three O atoms(Pt-O3)display the highest turnover number value of 3288 for the hydroboration reaction to access the important alkylboronic esters.Density functional theory calculations reveal that a superior catalytic activity can be expected for alkene hydroboration over the three O coordinated Pt species due to the lowest reaction energy(ΔG)limiting step from the reaction phase diagram.
基金finically supported by the National Key R&D Program of China(2017YFE0120500)the National Natural Science Foundation of China(51972129,51702150,and 21725102)+2 种基金the Key Research and Development Program of Hubei(2020BAB079)Bintuan Science and Technology Program(2020DB002,and 2022DB009)the Science and Technology Innovation Committee Foundation of Shenzhen(JCYJ20210324141613032 and JCYJ20190809142019365)。
文摘Anodic urea oxidation reaction(UOR)is an intriguing half reaction that can replace oxygen evolution reaction(OER)and work together with hydrogen evolution reaction(HER)toward simultaneous hydrogen fuel generation and urea-rich wastewater purification;however,it remains a challenge to achieve overall urea electrolysis with high efficiency.Herein,we report a multifunctional electrocatalyst termed as Rh/Ni V-LDH,through integration of nickel-vanadium layered double hydroxide(LDH)with rhodium single-atom catalyst(SAC),to achieve this goal.The electrocatalyst delivers high HER mass activity of0.262 A mg^(-1) and exceptionally high turnover frequency(TOF)of 2.125 s^(-1) at an overpotential of100 m V.Moreover,exceptional activity toward urea oxidation is addressed,which requires a potential of 1.33 V to yield 10 mA cm^(-2),endorsing the potential to surmount the sluggish OER.The splendid catalytic activity is enabled by the synergy of the Ni V-LDH support and the atomically dispersed Rh sites(located on the Ni-V hollow sites)as evidenced both experimentally and theoretically.The selfsupported Rh/Ni V-LDH catalyst serving as the anode and cathode for overall urea electrolysis(1 mol L^(-1) KOH with 0.33 mol L^(-1) urea as electrolyte)only requires a small voltage of 1.47 V to deliver 100 mA cm^(-2) with excellent stability.This work provides important insights into multifunctional SAC design from the perspective of support sites toward overall electrolysis applications.
基金supported by Taishan Scholars Program of Shandong Province(No.tsqn201909065)Shandong Provincial Natural Science Foundation(Nos.ZR2021YQ15 and ZR2020QB174)+1 种基金the National Natural Science Foundation of China(No.22108306)Postgraduate Innovation Fund of China University of Petroleum(East China)(No.YCX2021064)。
文摘Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)is considered an efficient way to convert CO_(2)into high-value-added chemicals,and thus is of significant social and economic value.Metal single-atomic site catalysts(SASCs)generally have excellent selectivity because of their 100%atomic utilization and uniform structure of active sites,and thus promise a broad range of applications.However,SASCs still face challenges such as low intrinsic activity and low density of active sites.Precise regulation of the microstructures of SASCs is an effective method to improve their CO_(2)RR performance and to obtain deep reduction products.In this article,we systematically summarize the current research status of SASCs developed for highly efficient catalysis of CO_(2)RR,discuss the various structural regulation methods for enhanced activity and selectivity of SASCs for CO_(2)RR,and review the application of in-situ characterization technologies in the SASC-catalyzed CO_(2)RR.We then discuss the problems yet to be solved in this area,and propose the future directions of the research on the design and application of SASCs for CO_(2)RR.
基金National Natural Science Foundation of China,Grant/Award Number:52171199。
文摘Dual-metal single-atom catalysts(DACs),featuring high atomic utilization efficiency,excellent selectivity,and stability originating from the atomically dispersed nature,have emerged as a new frontier in heterogeneous electrocatalysis due to the synergistic effect between diversified metal active sites in promoting their catalytic activity.In this review,the recent progress and development on the syntheses,characterizations,theoretical uniqueness,and applications for various catalytic reactions and devices(oxygen reduction reaction,oxygen evolution reaction,hydrogen evolution reaction,CO_(2) reduction reaction,N2 reduction reaction,proton exchange membrane fuel cells)are summarized and reviewed.Specifically,the synergistic effect between the two metal centers and electronic structures of catalysts is systematically discussed.Moreover,the future challenges and prospects in developing practical DACs are proposed as a possible direction for further investigation.
基金support from the National Natural Science Foundation of China(Nos.51932001,51872024,52022097,22293043)the National Key Research and Development Program of China(No.2018YFA0703503)the Foundation of the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2020048)。
文摘Single-atom catalysts(SACs)with high catalytic activity as well as great stability are demonstrating great promotion in electrocatalytic energy conversion,which is also a big challenge to achieve.Herein,we proposed a facile synthetic strategy to construct nickel-iron bimetallic hydroxide nanoribbon stabilized single-atom iridium catalysts(Ir-NiFe-OH),where the nickel-iron hydroxide nanoribbon not only can serve as good electronic conductor,but also can well stabilize and fully expose single-atom sites.Adopted as catalyst for urea oxidation reaction(UOR),it exhibited excellent UOR performance that it only needed a low operated potential of 1.38 V to achieve the current density of 100 mA·cm^(-2).In-situ Fourier transform infrared spectroscopy,X-ray absorption spectrum,and density functional theory calculations proved that Ir species are active centers and the existence of both Ni and Fe in the local structure of Ir atom can optimize the d-band center of Ir species,promoting the adsorption of intermediates and desorption of products for UOR.The hydrogen evolution reaction(HER)/UOR electrocatalytic cell demanded voltages of 1.46 and 1.50 V to achieve 50 and 100 mA·cm^(-2),respectively,which demonstrated a higher activity and better stability than those of conventional catalysts.This work opens a new avenue to develop catalysts for UORs with boosted activity and stability.
基金financially supported by the National Natural Science Foundation of China(Nos.11974303 and 12074332)the Qinglan Project(No.337050073)of Jiangsu Province+2 种基金the High-End Talent Program(No.137080210)the Yangzhou University Interdisciplinary Research Project of Chemistry Discipline(No.yzuxk202014)the Innovative Science and Technology Platform Project of Cooperation between Yangzhou City and Yangzhou University(No.YZ2020263).
文摘The use of single-atom cocatalysts plays a crucial role in enhancing artificial photocatalysis,where the precise construction of stable and efficient single-atom configuration is essential but remains challenging.Here,we report a simple one-step hydrothermal method for preparing single-atomic Mo modified ZnIn_(2)S_(4)(Mo-ZIS)nanosheets as a highly active photocatalytic hydrogen evolution(PHE)photocatalyst.The Mo substituting for portion of In atoms in ZIS nanosheets induces the spatial charge redistribution,which not only promotes the separation of photogenerated charge carriers but also optimizes the Gibbs free energy of adsorbing H*on S atoms at basal planes.As a result,Mo-ZIS exhibits an impressive PHE rate as high as 6.71 mmol·g^(−1)·h^(−1),over 10 times that of the pristine ZIS,with an apparent quantum efficiency(AQE)up to 38.8%at 420 nm.This study gains insights into the coordination configuration and electronic modulation resulting from single-atomic decoration,providing mechanistic cognitions for the development of advanced photocatalysts via non-precious metal atomic modification.
文摘Solving the problems of carbon dioxide(CO_(2))emissions and energy scarcity by the development of highly selective,cost-effective,and reliable catalysts for the electrochemical reduction of CO_(2)to useful carbon-based products would be very helpful.We report the synthesis of an efficient graphene-supported bismuth single-atom catalyst(BiSA-G)featuring a BiN_(4)coordination structure for this purpose.The synthesis used tannic acid as a multifunctional ligand and ammonia as a nitrogen dopant.Using a scalable coordination chemistry approach,BiN_(4)sites were uniformly dispersed on the graphene substrate and were found to have an outstanding ability for the conversion of CO_(2)to CO,with a high Faradaic efficiency of 97.4%at−0.55 V(vs.RHE)and a high turnover frequency of 5230 h^(−1)along with outstanding stability.Density functional theory calculations confirmed that the BiN_(4)site serves as the dominant active center,simultaneously facilitating CO_(2)activation and the efficient formation of the crucial intermediate*COOH with a reduced free energy barrier.This discovery offers a new way for the atomic-scale design of high-efficiency catalysts for the electrochemical CO_(2)reduction reaction,potentially helping sustainable carbon use.
文摘In recent years,numer-ous single-atom catalysts(SACs)have been synthesized to activate persulfate(PS)by a non-radical pathway because of its high se-lectivity,and activity for the cata-lyst.Metal-nitrogen-carbon(M-N_(x)-C)has been identified as the key active site in SACs.Although methods for preparing SACs have been extensively reported,a systematic summary of the direct construction of M-N_(x)-C,espe-cially unconventional metal-nitrogen-carbon(UM-N_(x)-C,x≠4),on SACs for PS non-radical activation has still not been reported.The role of the M-N_(x)-C active sites on PS non-radical activation is discussed and methods for the formation of M-N_(x)-C and UM-N_(x)-C active sites in SACs and the effect of catalyst carriers such as carbon nitride(g-C_(3)N_(4)),MOFs,COFs,and other car-bon materials are reviewed.Direct and indirect methods,especially for UM-N_(x)-C active site formation,are also elaborated.Factors affecting the formation of a M-N_(x)-C active site on SACs are also discussed.Prospects for the use of M-N_(x)-C active sites for the non-radical activation of PS by SACs to remove organic contaminants from wastewater are evaluated.
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.
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.
