Lithium–carbon dioxide(Li–CO_(2))batteries have attracted considerable attention due to their high theoretical energy densities and potential for capturing and converting CO_(2)toward net-zero carbon dioxide emissio...Lithium–carbon dioxide(Li–CO_(2))batteries have attracted considerable attention due to their high theoretical energy densities and potential for capturing and converting CO_(2)toward net-zero carbon dioxide emissions.However,the reversible cycling capability of Li–CO_(2)batteries is greatly limited by the sluggish kinetics of the CO_(2)evolution reaction(CO_(2)ER),which leads to excessive charge voltages exceeding 4.0 V,thus significantly hindering the practical advancement of the battery technology.Herein,we report dual-active-site AuRu catalysts supported on TiO_(2)nanorod arrays,grown on carbon nanofiber,where TiO_(2)layers effectively prevent carbon corrosion and the electronic synergy of the dual active site design comprising Au and Ru can lower the reaction energy barriers of the CO_(2)reduction reaction(CO_(2)RR)and CO_(2)ER.Calculation results reveal that this synergy gives rise to complementary catalytic roles:Au facilitates CO_(2)activation,whereas Ru promotes Li_(2)CO_(3)breakdown,collectively enhancing the overall reaction kinetics.Consequently,Li–CO_(2)batteries employing AuRu/TiO_(2)cathode deliver an ultralong cycle life exceeding 1100 cycles(~2200 h),low charge voltages(2.9–3.1 V),high energy efficiency(~77.9%),and excellent stability at elevated temperatures.This work establishes a generalizable catalyst-support strategy for long lifespan metal–CO_(2)batteries,offering a promising route toward high-performance carbon neutral energy storage devices.展开更多
The rational control of the active site of metal-organic frameworks(MOFs)derived nanomaterials is essential to build efficient bifunctional oxygen reduction/evolution reaction(ORR/OER)catalysts.Accordingly,through des...The rational control of the active site of metal-organic frameworks(MOFs)derived nanomaterials is essential to build efficient bifunctional oxygen reduction/evolution reaction(ORR/OER)catalysts.Accordingly,through designing and constructing a Co_(3)O_(4)-Co heterostructure embedded in Co,N co-doped carbon polyhedra derived(Co_(3)O_(4)-Co@NC)from the in-situ compositions of ZIF-67 and cobalt nanocrystals synthesized by the strategy of in-situ NaBH4 reduction,the dual-active site(Co_(3)O_(4)-Co and Co-N_(x))is synchronously realized in a MOFs derived nanomaterials.The formed Co_(3)O_(4)-Co@NC shows excellent bifunctional electrocatalytic activity with ultra-small potential gap(ΔE=E_(j=10)(OER)–E_(1/2)(ORR))of 0.72 V,which surpasses the commercial Pt/C and RuO_(2) catalysts.The theory calculation results reveal that the excellent bifunctional electrocatalytic activity can be attributed to the charge redistribution of Co of Co-N_(x) induced by the synergistic effects of well-tuned active sites of Co_(3)O_(4)-Co nanoparticle and Co-N_(x),thus optimizing the rate-determining step of the desorption of O_(2)^(*)intermediate in ORR and OH^(*)intermediate in OER.The rechargeable Zn-air batteries with our bifunctional catalysts exhibit superior performance as well as high cycling stability.This simple-effective optimization strategy offers prospects for tuning the active site of MOF derived bifunctional catalyst in electrochemical energy devices.展开更多
Dual-active sites(DASs)catalysts have positive potential applications in broad fields because of their specific active sites and synergistic catalytic effects.Therefore,the controllable synthesis and finely regulating...Dual-active sites(DASs)catalysts have positive potential applications in broad fields because of their specific active sites and synergistic catalytic effects.Therefore,the controllable synthesis and finely regulating the activity of such catalysts has become a hot research area for now.In this work,we developed a pyrolysis-etching-hydrogen activation strategy to prepare the DASs catalysts involving single-atom Cu and B on N-doped porous carbon material(Cu_(1)-B/NPC).Numerous systematic characterization and density functional theoretical(DFT)calculation results showed that the Cu and B existed as Cu-N4 porphyrinlike unit and B-N_(3)unit in the obtained catalyst.DFT calculations further revealed that single-atom Cu and B sites were linked by bridging N atoms to form the Cu_(1)-B-N6 dual-sites.The Cu_(1)-B/NPC catalyst was more effective than the single-active site catalysts with B-N_(3)sites in NPC(B/NPC)and Cu-N4 porphyrin-like sites in NPC(Cu_(1)/NPC),respectively,for the dehydrogenative coupling of dimethylphenylsilane(DiMPSH)with various alcohols,performing the great activity(>99%)and selectivity(>99%).The catalytic performances of the Cu_(1)-B/NPC catalyst remained nearly unchanged after five cycles,also indicating its outstanding recyclability.DFT calculations showed that the Cu_(1)-B-N6 dual-sites exhibited the lowest energy profile on the potential energy surface than that of sole B-N_(3)and Cu-N4 porphyrin-like sites.Furthermore,the rate-limiting step of dehydrogenation of DiMPSH on Cu_(1)-B-N6 dual-sites also showed a much lower activation energy than the other two single sites.Benefitting from the superiority of the Cu_(1)-B-N6 dual-sites,the Cu_(1)-B/NPC catalyst can also be used for CO_(2)electroreduction to produce syngas.Thus,DASs catalysts are promising to achieve multifunctional catalytic properties and have aroused positive attention in the field of catalysis.展开更多
Long-cycling dendrite-free solid-state lithium metal batteries (LMBs) require fast and uniform lithium-ion (Liþ)transport of solid-state electrolytes (SSEs). However, the SSEs still face the problems of low ionic...Long-cycling dendrite-free solid-state lithium metal batteries (LMBs) require fast and uniform lithium-ion (Liþ)transport of solid-state electrolytes (SSEs). However, the SSEs still face the problems of low ionic conductivity, lowLiþ transference number, and unstable interface with lithium metal. In this work, a novel strategy of frustratedLewis pairs (FLPs) modulating solid polymer electrolytes (SPEs) has been firstly proposed that enables durable Lireversible cycling. The tunable strength of Lewis acid and base dual-active sites of nickel borate FLPs can syn-ergisticallypromote both the dissociation of lithium salts and the transfer of Liþ. As a consequence, the FLPsmodulated SPEs (SPE-NiBO-150) exhibit high ionic conductivity of 4.92×10^(-4)S cm^(-1), high Liþ transferencenumber of 0.74, and superior interface compatibility with both lithium anode and LiFePO4 cathode at room-temperature.The Li//SPE-NiBO-150//Li symmetric cell demonstrates ultralong cycle stability (over 10,000 h(417 days) at both current density of 0.2 and 0.5 mA cm〓〓2), and the assembled solid-state LiFePO4//SPE-NiBO-150//Libattery also shows excellent performance (86% capacity retention for 300 cycles at 0.5C). The presentwork supplies a new insight into designing high-performance SPEs for solid-state LMB applications.展开更多
Multifunctional drug delivery systems(DDSs)have shown great prospects in overcoming the heterogeneous barrier of delivery drugs to the complex tumor microenvironment(TME).In this study,multifunctional AS/Ge-pNAB micro...Multifunctional drug delivery systems(DDSs)have shown great prospects in overcoming the heterogeneous barrier of delivery drugs to the complex tumor microenvironment(TME).In this study,multifunctional AS/Ge-pNAB microgels with dual-active targeting,triple environment responsiveness,and fluorescence imaging capability were prepared through a straightforward procedure.This was aimed to improve the antitumor therapeutic application of gambogic acid(GA)based on the biological characteristics of TME.The microgels have a uniform double-layer structure with aptamer in the outer layer which helps in recognizing receptors on the tumor cells.The GA loaded nano-herb exhibited environment-responsive drug release profiles under acidic pH,reductant and high temperature.The nano-herb significantly improved the accumulation of GA in tumor sites through the synergistic combination of the enhanced permeability and retention effect and dual-ligand mediated internalization.Then,it accelerated intracellular drug release and killed tumor cells.Therefore,the nano-herb had specific therapeutic effects on the tumor in vitro and in vivo as they remarkably inhibited tumor growth while depicting optimal biosafety and lower levels of off-target toxicity.Overall,these findings demonstrate the great potential of the multifunctional AS/Ge-pNAB microgels for precisely targeted GA delivery and open a new avenue for the facile preparation of multifunctional DDSs.展开更多
As a desirable alternative for oxygen evolution reaction(OER),urea oxidation reaction(UOR)with the effectively reduced overpotential has attracted considerable attention in pollutant degradation and rechargeable Zn-ai...As a desirable alternative for oxygen evolution reaction(OER),urea oxidation reaction(UOR)with the effectively reduced overpotential has attracted considerable attention in pollutant degradation and rechargeable Zn-air battery(ZAB).Herein,a bifunctional electrocatalyst with CoNi alloy and Co-N dual active sites encapsulated by nitrogen-doped carbon nanotubes have been rationally designed and successfully prepared.The as-obtained catalyst CoNi/Co-NCNT displays excellent catalytic activity for oxygen reduction(ORR)and UOR with a narrow potential difference of 0.56 V.The urea-assisted rechargeable ZABs based on CoNi/Co-NCNT provide higher energy conversion efficiency(61%),15%higher than that of conventional ZABs.In addition to verify the UOR pathway on the CoNi/Co-NCNT,DFT calculations reveal that CoNi alloy and Co-N in CoNi/Co-NCNT synergistically function as the main active sites for ORR and UOR.The excellent ORR catalytic performance and the superior energy conversion efficiency of CoNi/Co-NCNT based urea-assisted rechargeable ZAB is expected to accelerate the practical application of ZAB technology.This work paved a new way for the development of bifunctional catalysts for higher efficiency ZABs,and also provides a potential scheme for disposing urea rich wastewater.展开更多
The conventional synthesis of fine chemicals through multi-step independent reactions frequently necessitates intermittent catalyst substitution and laborious intermediate purification,posing significant challenges to...The conventional synthesis of fine chemicals through multi-step independent reactions frequently necessitates intermittent catalyst substitution and laborious intermediate purification,posing significant challenges to process efficiency and energy sustainability.Herein,we developed a polyoxometalate(POM)-mediated defect engineering strategy to construct a spatially isolated but functionally coupled oxidation-amination dual-active sites by confining H5PV_(2)Mo_(10)O_(40)({PV_(2)Mo_(10)})in UiO-66({PV_(2)Mo_(10)}-0.1@UiO-66),achieving a one-pot two-step tandem conversion of alkenes to amino alcohols.The complete conversion process begins with{PV_(2)Mo10}-catalyzed highly selective epoxidation of the alkenes(step A),followed by the in situ ring-opening amination of the epoxide intermediate by direct addition of the amine under the catalysis of the defective sites on UiO-66,without catalyst replacement and intermediate separation.Spectroscopic and catalytic performance analysis confirmed that the{PV_(2)Mo_(10)}-0.1@UiO-66 with dual-active sites has continuous reaction and multi-cycle structural stability.Based on the rich functionality of POMs and metal-organic frameworks(MOFs),their diverse assembly will provide a modular design platform for catalyst design aimed at tandem reactions.展开更多
The low-temperature transformation of CO_(2)and CH_(3)OH into dimethyl carbonate(DMC)represents a sustainable and low-carbon pathway for producing essential chemicals.An ideal energy-efficient catalysis necessitates a...The low-temperature transformation of CO_(2)and CH_(3)OH into dimethyl carbonate(DMC)represents a sustainable and low-carbon pathway for producing essential chemicals.An ideal energy-efficient catalysis necessitates a catalyst capable of facilitating interactions between the simultaneously activated CO_(2)and CH_(3)OH.Herein,we designed the spatially proximate In_(5)and In_(4+1)…In_(4)sites on the In_(2)O_(3)surface,enabling efficient DMC synthesis from CO_(2)and CH_(3)OH below 100℃.The In_(5)sites are responsible for CH_(3)OH adsorption;while CO_(2)adsorbs on the In_(4+1)…In_(4)pairs through interactions between its O atom with two In sites,as well as between the C atom and a lattice O atom.Furthermore,the spatial intimacy of In_(5)and In_(4+1)…In_(4)sites,with a distance of~4.7Å,facilitate direct interaction between the adsorbed CO_(2)and CH_(3)OH.By optimizing oxygen vacancies,porous In_(2)O_(3)nanocubes with abundant dual-active sites achieved a DMC generation rate of 8.1 mmol·gcat^(-1)·h^(-1)at 100℃,significantly surpassing previously reported catalysts.These findings demonstrate a promising route for the energy-efficient DMC synthesis from CO_(2)and CH_(3)OH.展开更多
The electric vehicle(EV)charging station is a critical part of the infrastructure for the wide adoption of EVs.Realtime simulation of an EV station plays an essential role in testing its operation under different oper...The electric vehicle(EV)charging station is a critical part of the infrastructure for the wide adoption of EVs.Realtime simulation of an EV station plays an essential role in testing its operation under different operating modes.However,the large numbers of high-frequency power electronic switches contained in EV chargers pose great challenges for real-time simulation.This paper proposes a compact electromagnetic transient program(C-EMTP)algorithm for FPGA-based real-time simulation of an EV station with multiple high-frequency chargers.The C-EMTP algorithm transforms the traditional EMTP algorithm into two parallel sub-tasks only consisting of simple matrix operations,to fully utilize the high parallelism of FPGA.The simulation time step can be greatly reduced compared with that of the traditional EMTP algorithm,and so the simulation accuracy for high-frequency power electronics is improved.The EV chargers can be decoupled with each other and simulated in parallel.A CPU-FPGA-based realtime simulation platform is developed and the proposed simulation of the EV station is implemented.The control strategy is simulated in a CPU with 100μs time-step,while the EV station circuit topology is simulated in a single FPGA with a 250 ns time-step.In the case studies,the EV station consists of a two-level rectifier and five dual-active bridge(DAB)EV chargers.It is tested under different scenarios,and the real-time simulation results are validated using PSCAD/EMTDC.展开更多
The design of high-performance catalysts is the key to the efficient utilization of hydrogen energy.In this work,a PdCu nanoalloy was successfully anchored on TiO_(2)encapsulated with carbon to construct a catalyst.Ou...The design of high-performance catalysts is the key to the efficient utilization of hydrogen energy.In this work,a PdCu nanoalloy was successfully anchored on TiO_(2)encapsulated with carbon to construct a catalyst.Outstanding kinetics of the hydrolysis of ammonia borane(turnover frequency of 279 mol·min^(-1·)mol_(Pd)^(-1))ranking the third place among Pd-based catalysts was achieved in the absence of alkali.Both experimental research and theoretical calculations reveal a lower activation energy of the B-H bond on the PdCu nanoalloy catalyst than that on pristine Pd and a lower activation energy of the O-H bond than that on pristine Cu.The redistribution of d electron and the shift of the d-band center play a critical role in increasing the electron density of Pd and improving the catalytic performances of Pd_(0.1)Cu_(0.9)/TiO_(2)-porous carbon(Pd_(0.1)Cu_(0.9)/T-PC).This work provides novel insights into highly dual-active alloys and sheds light on the mechanism of dual-active sites in promoting borohydride hydrolysis.展开更多
The presence of renewable energy resources in LV distribution networks may lead to a distribution transformer,also known as a Smart Transformer(ST),experiencing the bidirectional power flow.Therefore,the ST must have ...The presence of renewable energy resources in LV distribution networks may lead to a distribution transformer,also known as a Smart Transformer(ST),experiencing the bidirectional power flow.Therefore,the ST must have the capability to operate in both directions.However,the reverse power is less as compared to the forward power,thus the design of ST with the same capacity in both directions increases the hardware cost and decreases the system efficiency.This paper proposes a Hybrid-modular-ST(H-ST),composed of a mixed use of single active bridge-based series resonant converter and dual active bridge instead of complete use of uni-or bi-directional converter adopted in the conventional solid-state-transformer.Based on the proposed H-ST,the impacts of power imbalance among cascaded modules in reverse operation mode are analyzed and then an effective solution based on reactive power compensation combined with the characteristics of the proposed architecture is adopted.The simulation and experimental results clearly validate the effectiveness and feasibility of the theoretical analyses.展开更多
基金supported financially by the National Natural Science Foundation of China(No.62105048)the Key R&D Project of Nantong(No.2024004)+1 种基金the Postdoctoral Science Foundation of China(No.2021M693768)Open Project of the National Laboratory of Solid-State Microstructure(No.M37050).
文摘Lithium–carbon dioxide(Li–CO_(2))batteries have attracted considerable attention due to their high theoretical energy densities and potential for capturing and converting CO_(2)toward net-zero carbon dioxide emissions.However,the reversible cycling capability of Li–CO_(2)batteries is greatly limited by the sluggish kinetics of the CO_(2)evolution reaction(CO_(2)ER),which leads to excessive charge voltages exceeding 4.0 V,thus significantly hindering the practical advancement of the battery technology.Herein,we report dual-active-site AuRu catalysts supported on TiO_(2)nanorod arrays,grown on carbon nanofiber,where TiO_(2)layers effectively prevent carbon corrosion and the electronic synergy of the dual active site design comprising Au and Ru can lower the reaction energy barriers of the CO_(2)reduction reaction(CO_(2)RR)and CO_(2)ER.Calculation results reveal that this synergy gives rise to complementary catalytic roles:Au facilitates CO_(2)activation,whereas Ru promotes Li_(2)CO_(3)breakdown,collectively enhancing the overall reaction kinetics.Consequently,Li–CO_(2)batteries employing AuRu/TiO_(2)cathode deliver an ultralong cycle life exceeding 1100 cycles(~2200 h),low charge voltages(2.9–3.1 V),high energy efficiency(~77.9%),and excellent stability at elevated temperatures.This work establishes a generalizable catalyst-support strategy for long lifespan metal–CO_(2)batteries,offering a promising route toward high-performance carbon neutral energy storage devices.
基金The authors acknowledge support from the National Natural Science Foundation of China(No.21875039)Minjiang Professorship(XRC-1677)+1 种基金Fujian province’s high level innovative and entrepreneurial talents(No.50012709)the Open Project Program of the State Key Laboratory of Photocatalysis on Energy and Environment(No.SKLPEE-201814),Fuzhou University.
文摘The rational control of the active site of metal-organic frameworks(MOFs)derived nanomaterials is essential to build efficient bifunctional oxygen reduction/evolution reaction(ORR/OER)catalysts.Accordingly,through designing and constructing a Co_(3)O_(4)-Co heterostructure embedded in Co,N co-doped carbon polyhedra derived(Co_(3)O_(4)-Co@NC)from the in-situ compositions of ZIF-67 and cobalt nanocrystals synthesized by the strategy of in-situ NaBH4 reduction,the dual-active site(Co_(3)O_(4)-Co and Co-N_(x))is synchronously realized in a MOFs derived nanomaterials.The formed Co_(3)O_(4)-Co@NC shows excellent bifunctional electrocatalytic activity with ultra-small potential gap(ΔE=E_(j=10)(OER)–E_(1/2)(ORR))of 0.72 V,which surpasses the commercial Pt/C and RuO_(2) catalysts.The theory calculation results reveal that the excellent bifunctional electrocatalytic activity can be attributed to the charge redistribution of Co of Co-N_(x) induced by the synergistic effects of well-tuned active sites of Co_(3)O_(4)-Co nanoparticle and Co-N_(x),thus optimizing the rate-determining step of the desorption of O_(2)^(*)intermediate in ORR and OH^(*)intermediate in OER.The rechargeable Zn-air batteries with our bifunctional catalysts exhibit superior performance as well as high cycling stability.This simple-effective optimization strategy offers prospects for tuning the active site of MOF derived bifunctional catalyst in electrochemical energy devices.
基金supported by the National Natural Science Foundation of China(Nos.51902003,22002085,21771003,21501004)the University Synergy Innovation Program of Anhui Province(No.GXXT-2021-020)+4 种基金the Anhui Province Natural Science Foundation(Nos.2108085QB71 and 2008085QB53)the Natural Science Research Project of Anhui Province Education Department(No.KJ2019A0581)the Open Project of Key Laboratory of Metallurgical Emission Reduction&Resources Recycling of Ministry of Education(No.JKF21-03)the Open Foundation of Anhui Laboratory of Clean Catalytic Engineering(No.LCCE-01)the Open Research Funds of Jiangxi Province Engineering Research Center of Ecological Chemical Industry(STKF2109).
文摘Dual-active sites(DASs)catalysts have positive potential applications in broad fields because of their specific active sites and synergistic catalytic effects.Therefore,the controllable synthesis and finely regulating the activity of such catalysts has become a hot research area for now.In this work,we developed a pyrolysis-etching-hydrogen activation strategy to prepare the DASs catalysts involving single-atom Cu and B on N-doped porous carbon material(Cu_(1)-B/NPC).Numerous systematic characterization and density functional theoretical(DFT)calculation results showed that the Cu and B existed as Cu-N4 porphyrinlike unit and B-N_(3)unit in the obtained catalyst.DFT calculations further revealed that single-atom Cu and B sites were linked by bridging N atoms to form the Cu_(1)-B-N6 dual-sites.The Cu_(1)-B/NPC catalyst was more effective than the single-active site catalysts with B-N_(3)sites in NPC(B/NPC)and Cu-N4 porphyrin-like sites in NPC(Cu_(1)/NPC),respectively,for the dehydrogenative coupling of dimethylphenylsilane(DiMPSH)with various alcohols,performing the great activity(>99%)and selectivity(>99%).The catalytic performances of the Cu_(1)-B/NPC catalyst remained nearly unchanged after five cycles,also indicating its outstanding recyclability.DFT calculations showed that the Cu_(1)-B-N6 dual-sites exhibited the lowest energy profile on the potential energy surface than that of sole B-N_(3)and Cu-N4 porphyrin-like sites.Furthermore,the rate-limiting step of dehydrogenation of DiMPSH on Cu_(1)-B-N6 dual-sites also showed a much lower activation energy than the other two single sites.Benefitting from the superiority of the Cu_(1)-B-N6 dual-sites,the Cu_(1)-B/NPC catalyst can also be used for CO_(2)electroreduction to produce syngas.Thus,DASs catalysts are promising to achieve multifunctional catalytic properties and have aroused positive attention in the field of catalysis.
基金supported by the National Natural Science Foundation of China(52162036,52174284 and 22378342)the Key Project of Nature Science Foundation of Xinjiang Province(2021D01D08)the Key Research and Development Program of Hunan Province(2024JK2094).
文摘Long-cycling dendrite-free solid-state lithium metal batteries (LMBs) require fast and uniform lithium-ion (Liþ)transport of solid-state electrolytes (SSEs). However, the SSEs still face the problems of low ionic conductivity, lowLiþ transference number, and unstable interface with lithium metal. In this work, a novel strategy of frustratedLewis pairs (FLPs) modulating solid polymer electrolytes (SPEs) has been firstly proposed that enables durable Lireversible cycling. The tunable strength of Lewis acid and base dual-active sites of nickel borate FLPs can syn-ergisticallypromote both the dissociation of lithium salts and the transfer of Liþ. As a consequence, the FLPsmodulated SPEs (SPE-NiBO-150) exhibit high ionic conductivity of 4.92×10^(-4)S cm^(-1), high Liþ transferencenumber of 0.74, and superior interface compatibility with both lithium anode and LiFePO4 cathode at room-temperature.The Li//SPE-NiBO-150//Li symmetric cell demonstrates ultralong cycle stability (over 10,000 h(417 days) at both current density of 0.2 and 0.5 mA cm〓〓2), and the assembled solid-state LiFePO4//SPE-NiBO-150//Libattery also shows excellent performance (86% capacity retention for 300 cycles at 0.5C). The presentwork supplies a new insight into designing high-performance SPEs for solid-state LMB applications.
基金financially supported by the National Natural Science Foundation of China(Nos.21907076 and 31901908)Natural Science Foundation of Tianjin(No.22JCQNJC01570)Scientific Project of Tianjin Municipal Education Commission(No.2022KJ026).
文摘Multifunctional drug delivery systems(DDSs)have shown great prospects in overcoming the heterogeneous barrier of delivery drugs to the complex tumor microenvironment(TME).In this study,multifunctional AS/Ge-pNAB microgels with dual-active targeting,triple environment responsiveness,and fluorescence imaging capability were prepared through a straightforward procedure.This was aimed to improve the antitumor therapeutic application of gambogic acid(GA)based on the biological characteristics of TME.The microgels have a uniform double-layer structure with aptamer in the outer layer which helps in recognizing receptors on the tumor cells.The GA loaded nano-herb exhibited environment-responsive drug release profiles under acidic pH,reductant and high temperature.The nano-herb significantly improved the accumulation of GA in tumor sites through the synergistic combination of the enhanced permeability and retention effect and dual-ligand mediated internalization.Then,it accelerated intracellular drug release and killed tumor cells.Therefore,the nano-herb had specific therapeutic effects on the tumor in vitro and in vivo as they remarkably inhibited tumor growth while depicting optimal biosafety and lower levels of off-target toxicity.Overall,these findings demonstrate the great potential of the multifunctional AS/Ge-pNAB microgels for precisely targeted GA delivery and open a new avenue for the facile preparation of multifunctional DDSs.
基金supported by the National Natural Science Foundation of China(22171166,22235001 and 52371229)。
文摘As a desirable alternative for oxygen evolution reaction(OER),urea oxidation reaction(UOR)with the effectively reduced overpotential has attracted considerable attention in pollutant degradation and rechargeable Zn-air battery(ZAB).Herein,a bifunctional electrocatalyst with CoNi alloy and Co-N dual active sites encapsulated by nitrogen-doped carbon nanotubes have been rationally designed and successfully prepared.The as-obtained catalyst CoNi/Co-NCNT displays excellent catalytic activity for oxygen reduction(ORR)and UOR with a narrow potential difference of 0.56 V.The urea-assisted rechargeable ZABs based on CoNi/Co-NCNT provide higher energy conversion efficiency(61%),15%higher than that of conventional ZABs.In addition to verify the UOR pathway on the CoNi/Co-NCNT,DFT calculations reveal that CoNi alloy and Co-N in CoNi/Co-NCNT synergistically function as the main active sites for ORR and UOR.The excellent ORR catalytic performance and the superior energy conversion efficiency of CoNi/Co-NCNT based urea-assisted rechargeable ZAB is expected to accelerate the practical application of ZAB technology.This work paved a new way for the development of bifunctional catalysts for higher efficiency ZABs,and also provides a potential scheme for disposing urea rich wastewater.
基金supported by the National Natural Science Foundation of China(No.22171035)Liaoning Provincial Science and Technology Programme Joint Programme(No.2024-MSLH-068)+1 种基金Liaoning Provincial Natural Science Foundation Joint Fund(Doctoral Research Start-up Project)(Nos.2023-BSBA-088 and 2023-BSBA-087),China Postdoctoral Science Foundation(No.2024M750307)the fund of the State Key Laboratory of Catalysis in Dalian Institute of Chemical Physics(DICP),Chinese Academy of Sciences(No.N-21-08).
文摘The conventional synthesis of fine chemicals through multi-step independent reactions frequently necessitates intermittent catalyst substitution and laborious intermediate purification,posing significant challenges to process efficiency and energy sustainability.Herein,we developed a polyoxometalate(POM)-mediated defect engineering strategy to construct a spatially isolated but functionally coupled oxidation-amination dual-active sites by confining H5PV_(2)Mo_(10)O_(40)({PV_(2)Mo_(10)})in UiO-66({PV_(2)Mo_(10)}-0.1@UiO-66),achieving a one-pot two-step tandem conversion of alkenes to amino alcohols.The complete conversion process begins with{PV_(2)Mo10}-catalyzed highly selective epoxidation of the alkenes(step A),followed by the in situ ring-opening amination of the epoxide intermediate by direct addition of the amine under the catalysis of the defective sites on UiO-66,without catalyst replacement and intermediate separation.Spectroscopic and catalytic performance analysis confirmed that the{PV_(2)Mo_(10)}-0.1@UiO-66 with dual-active sites has continuous reaction and multi-cycle structural stability.Based on the rich functionality of POMs and metal-organic frameworks(MOFs),their diverse assembly will provide a modular design platform for catalyst design aimed at tandem reactions.
基金We acknowledge the Guangdong Basic and Applied Basic Research Foundation(No.2022B1515020092)Shenzhen Science and Technology Program(No.JCYJ20220530161600002)+1 种基金the key Projects of Natural Science Basic Research Program of Shannxi Province(No.2024JC-TBZC-16)supported by the Sponsored by Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(Nos.24GH01020101 and CX2024096).
文摘The low-temperature transformation of CO_(2)and CH_(3)OH into dimethyl carbonate(DMC)represents a sustainable and low-carbon pathway for producing essential chemicals.An ideal energy-efficient catalysis necessitates a catalyst capable of facilitating interactions between the simultaneously activated CO_(2)and CH_(3)OH.Herein,we designed the spatially proximate In_(5)and In_(4+1)…In_(4)sites on the In_(2)O_(3)surface,enabling efficient DMC synthesis from CO_(2)and CH_(3)OH below 100℃.The In_(5)sites are responsible for CH_(3)OH adsorption;while CO_(2)adsorbs on the In_(4+1)…In_(4)pairs through interactions between its O atom with two In sites,as well as between the C atom and a lattice O atom.Furthermore,the spatial intimacy of In_(5)and In_(4+1)…In_(4)sites,with a distance of~4.7Å,facilitate direct interaction between the adsorbed CO_(2)and CH_(3)OH.By optimizing oxygen vacancies,porous In_(2)O_(3)nanocubes with abundant dual-active sites achieved a DMC generation rate of 8.1 mmol·gcat^(-1)·h^(-1)at 100℃,significantly surpassing previously reported catalysts.These findings demonstrate a promising route for the energy-efficient DMC synthesis from CO_(2)and CH_(3)OH.
基金supported by China Postdoctoral Science Foundation(BX20200221,2020 M671122)National Key Research and Development Program of China(2019YFE012784)National Natural Science Foundation of China(51877133).
文摘The electric vehicle(EV)charging station is a critical part of the infrastructure for the wide adoption of EVs.Realtime simulation of an EV station plays an essential role in testing its operation under different operating modes.However,the large numbers of high-frequency power electronic switches contained in EV chargers pose great challenges for real-time simulation.This paper proposes a compact electromagnetic transient program(C-EMTP)algorithm for FPGA-based real-time simulation of an EV station with multiple high-frequency chargers.The C-EMTP algorithm transforms the traditional EMTP algorithm into two parallel sub-tasks only consisting of simple matrix operations,to fully utilize the high parallelism of FPGA.The simulation time step can be greatly reduced compared with that of the traditional EMTP algorithm,and so the simulation accuracy for high-frequency power electronics is improved.The EV chargers can be decoupled with each other and simulated in parallel.A CPU-FPGA-based realtime simulation platform is developed and the proposed simulation of the EV station is implemented.The control strategy is simulated in a CPU with 100μs time-step,while the EV station circuit topology is simulated in a single FPGA with a 250 ns time-step.In the case studies,the EV station consists of a two-level rectifier and five dual-active bridge(DAB)EV chargers.It is tested under different scenarios,and the real-time simulation results are validated using PSCAD/EMTDC.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.22279118,22279117,52071135,51871090,and U1804135)the Fundamental Research Funds for the Universities of Henan Province(No.NSFRF220201).
文摘The design of high-performance catalysts is the key to the efficient utilization of hydrogen energy.In this work,a PdCu nanoalloy was successfully anchored on TiO_(2)encapsulated with carbon to construct a catalyst.Outstanding kinetics of the hydrolysis of ammonia borane(turnover frequency of 279 mol·min^(-1·)mol_(Pd)^(-1))ranking the third place among Pd-based catalysts was achieved in the absence of alkali.Both experimental research and theoretical calculations reveal a lower activation energy of the B-H bond on the PdCu nanoalloy catalyst than that on pristine Pd and a lower activation energy of the O-H bond than that on pristine Cu.The redistribution of d electron and the shift of the d-band center play a critical role in increasing the electron density of Pd and improving the catalytic performances of Pd_(0.1)Cu_(0.9)/TiO_(2)-porous carbon(Pd_(0.1)Cu_(0.9)/T-PC).This work provides novel insights into highly dual-active alloys and sheds light on the mechanism of dual-active sites in promoting borohydride hydrolysis.
基金supported in part by National Key Research&Development Project of China(2017YFE0134300)in part by Shanghai 2022 Science and Technology Innovation Action Plan-Star Cultivation(Sailing Program)(22YF1415700)in part by the National Natural Science Foundation of China under Grant 52307215.
文摘The presence of renewable energy resources in LV distribution networks may lead to a distribution transformer,also known as a Smart Transformer(ST),experiencing the bidirectional power flow.Therefore,the ST must have the capability to operate in both directions.However,the reverse power is less as compared to the forward power,thus the design of ST with the same capacity in both directions increases the hardware cost and decreases the system efficiency.This paper proposes a Hybrid-modular-ST(H-ST),composed of a mixed use of single active bridge-based series resonant converter and dual active bridge instead of complete use of uni-or bi-directional converter adopted in the conventional solid-state-transformer.Based on the proposed H-ST,the impacts of power imbalance among cascaded modules in reverse operation mode are analyzed and then an effective solution based on reactive power compensation combined with the characteristics of the proposed architecture is adopted.The simulation and experimental results clearly validate the effectiveness and feasibility of the theoretical analyses.
