Two major challenges,high cost and short lifespan,have been hindering the commercialization process of lowtemperature fuel cells.Professor Wei's group has been focusing on decreasing cathode Pt loadings without lo...Two major challenges,high cost and short lifespan,have been hindering the commercialization process of lowtemperature fuel cells.Professor Wei's group has been focusing on decreasing cathode Pt loadings without losses of activity and durability,and their research advances in this area over the past three decades are briefly reviewed herein.Regarding the Pt-based catalysts and the low Pt usage,they have firstly tried to clarify the degradation mechanism of Pt/C catalysts,and then demonstrated that the activity and stability could be improved by three strategies:regulating the nanostructures of the active sites,enhancing the effects of support materials,and optimizing structures of the three-phase boundary.For Pt-free catalysts,especialiy carbon-based ones,several strategies that they proposed to enhance the activity of nitrogen-/heteroatom-doped carbon catalysts are firstly presented.Then,an indepth understanding of the degradation mechanism for carbon-based catalysts is discussed,and followed by the corresponding stability enhancement strategies.Also,the carbon-based electrode at the micrometer-scale,faces the challenges such as low active-site density,thick catalytic layer,and the effect of hydrogen peroxide,which require rational structure design for the integral cathodic electrode.This review finally gives a brief conclusion and outlook about the low cost and long lifespan of cathodic oxygen reduction catalysts.展开更多
Cobalt-free,nickel-rich LiNi_(1-x)Al_(x)O_(2)(x≤0.1)is an attractive cathode material because of high energy density and low cost but suffers from severe structural degradation and poor rate performance.In this study...Cobalt-free,nickel-rich LiNi_(1-x)Al_(x)O_(2)(x≤0.1)is an attractive cathode material because of high energy density and low cost but suffers from severe structural degradation and poor rate performance.In this study,we propose a molten salt-assisted synthesis in combination with a Li-refeeding induced aluminum segregation strategy to prepare Li_(5)AlO_(4)-coated single-crystalline slightly Li-rich Li_(1.04)Ni_(0.92)Al_(0.04)O_(2).The symbiotic formation of Li_(5)AlO_(4)from reaction between molten lithium hydroxide and doped aluminum in the bulk ensures a high lattice matching between the Ni-rich oxide and the homogenous conductive Li_(5)AlO_(4)that permits high Li^(+)conductivity.Benefiting from mitigated undesirable side reactions and phase evolution,the Li_(5)AlO_(4)-coated single-crystalline Li_(1.04)Ni_(0.92)Al_(0.04)O_(2)delivers a high specific capacity of220.2 mA h g^(-1)at 0.1 C and considerable rate capability(182.5 mA h g^(-1)at 10 C).Besides,superior capacity retention of 90.8%is obtained at 1/3 C after 100 cycles in a 498.1 mA h pouch full cell.Furthermore,the particulate morphology of Li_(1.04)Ni_(0.92)Al_(0.04)O_(2)remains intact after cycling at a cutoff voltage of 4.3 V,whereas slightly Li-deficient Li_(0.98)Ni_(0.97)Al_(0.05)O_(2)features intragranular cracks and irreversible lattice distortion.The results highlight the value of molten salt-assisted synthesis and Li-refeeding induced elemental segregation strategy to upgrade Ni-based layered oxide cathode materials for advanced Li-ion batteries.展开更多
Sodium-based storage devices based on conversion-type metal sulfide anodes have attracted great atten-tion due to their multivalent ion redox reaction ability.However,they also suffer from sodium polysul-fides(NaPSs)s...Sodium-based storage devices based on conversion-type metal sulfide anodes have attracted great atten-tion due to their multivalent ion redox reaction ability.However,they also suffer from sodium polysul-fides(NaPSs)shuttling problems during the sluggish Na^(+) redox process,leading to"voltage failure"and rapid capacity decay.Herein,a metal cobalt-doping vanadium disulfide(Co-VS_(2))is proposed to simulta-neously accelerate the electrochemical reaction of VS_(2) and enhance the bidirectional redox of soluble NaPSs.It is found that the strong adsorption of NaPSs by V-Co alloy nanoparticles formed in situ during the conversion reaction of Co-VS_(2) can effectively inhibit the dissolution and shuttle of NaPSs,and ther-modynamically reduce the formation energy barrier of the reaction path to effectively drive the complete conversion reaction,while the metal transition of Co elements enhances reconversion kinetics to achieve high reversibility.Moreover,Co-VS_(2) also produce abundant sulfur vacancies and unsaturated sulfur edge defects,significantly improve ionic/electron diffusion kinetics.Therefore,the Co-VS_(2) anode exhibits ultrahigh rate capability(562 mA h g^(-1) at 5 A g^(-1)),high initial coulombic efficiency(~90%)and 12,000 ultralong cycle life with capacity retention of 90%in sodium-ion batteries(SIBs),as well as impressive energy/power density(118 Wh kg^(-1)/31,250 W kg^(-1))and over 10.000 stable cycles in sodium-ion hybrid capacitors(SIHCs).Moreover,the pouch cell-type SIHC displays a high-energy density of 102 Wh kg^(-1) and exceed 600 stable cycles.This work deepens the understanding of the electrochemical reaction mechanism of conversion-type metal sulfide anodes and provides a valuable solution to the shuttlingofNaPSs inSIBsandSIHCs.展开更多
Charge transfer at the liquid(electrolyte)-solid(metal)interfaces is of fundamental importance to metal electrochemical deposition that further determines the reversibility and kinetics of energy-dense rechargeable me...Charge transfer at the liquid(electrolyte)-solid(metal)interfaces is of fundamental importance to metal electrochemical deposition that further determines the reversibility and kinetics of energy-dense rechargeable metal batteries(RMBs).We demonstrate the fast charge transfer at the electrolyte-metal interfaces for lithium metal by designing and synthesizing electrolytes with chiral solvents:R(or S)-1,2-dimethoxy pro pane(R-DMP or S-DMP)and R(or S)-4-methyl-1,3-dioxolane(R-MDOL or S-MDOL).The chiral-induced spin selectivity is considered to produce spin-polarized metal surfaces,enabling the improvement in charge transfer rate and efficiency.The deposited Li metal in chiral electrolytes shows smooth and uniform morphologies,as well as high initial(>95%)and average(~99.2%)Coulombic efficiency for Li metal stripping/plating process,thus prolonging the life-span of batteries using thin lithium anode(50μm)to 400 cycles till 80%capacity retention.This work provides a distinct approach to regulate metal deposition beyond the limitation of ion de-solvation.展开更多
With the rapid development of consumer electronics and electric vehicles(EV), a large number of spent lithium-ion batteries(LIBs) have been generated worldwide. Thus, effective recycling technologies to recapture a si...With the rapid development of consumer electronics and electric vehicles(EV), a large number of spent lithium-ion batteries(LIBs) have been generated worldwide. Thus, effective recycling technologies to recapture a significant amount of valuable metals contained in spent LIBs are highly desirable to prevent the environmental pollution and resource depletion. In this work, a novel recycling technology to regenerate a LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2 cathode material from spent LIBs with different cathode chemistries has been developed. By dismantling, crushing,leaching and impurity removing, the LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2(selected as an example of LiNi_xCo_yMn_(1-x-y)O_2) powder can be directly prepared from the purified leaching solution via co-precipitation followed by solid-state synthesis. For comparison purposes, a fresh-synthesized sample with the same composition has also been prepared using the commercial raw materials via the same method. X-ray diffraction(XRD), scanning electron microscopy(SEM) and electrochemical measurements have been carried out to characterize these samples. The electrochemical test result suggests that the re-synthesized sample delivers cycle performance and low rate capability which are comparable to those of the freshsynthesized sample. This novel recycling technique can be of great value to the regeneration of a pure and marketable LiNi_xCo_yMn_(1-x-y)O_2 cathode material with low secondary pollution.展开更多
Lithium-sulfur battery is desirable for the future potential electrochemical energy storage device with advantages of high theoretical energy density,low cost and environmental friendliness.However,some natural hindra...Lithium-sulfur battery is desirable for the future potential electrochemical energy storage device with advantages of high theoretical energy density,low cost and environmental friendliness.However,some natural hindrances,particularly fast capacity degradation resulting from the migration of dissolved polysulfide intermediates,remain to be significant challenges prior to the practical applications.In this work,a composite interlayer of carbon nanofibers(CNFs)which are enriched by Co-based metal organic frameworks(ZIF-67)growth in-situ is exploited.Notably,physical blocking and chemical trapping abilities are obtained synergistically from the ZIF/CNFs interlayer,which enables to restrain the dissolution of polysulfides and alleviate shuttle effect.Moreover,the three-dimensional fiber networks provide an interconnected conductive framework between each ZIF microreactor to promote fast electron transfer during cycling,thus contributing to excellent rate and cycling performance.As a result,Li-S cells with ZIF/CNFs interlayer show a high specific capacity of 1334 mAh g^(-1) at 1 C with an excellent cycling stability over 300 cycles.Besides,this scalable and affordable electrospinning fabrication method provides a promising approach for the design of MOFs-derived carbon materials for high performance Li-S batteries.展开更多
Lithium–sulfur(Li-S) battery is considered as one of the most promising candidates for future portable electronics and electric vehicles due to high energy density and potentially low cost. However, the severe polysu...Lithium–sulfur(Li-S) battery is considered as one of the most promising candidates for future portable electronics and electric vehicles due to high energy density and potentially low cost. However, the severe polysulfides shuttling in Li-S battery always causes low Coulombic efficiency, capacity fading, and hindering its practical commercialization. Herein, a dualfunctional PEI@MWCNTs-CB/MWCNTs/PP(briefly denoted as PMS)separator is assembled through Langmuir–Blodgett–Scooping(LBS) technique for improvement of Li-S battery performance, that is, rational integrating conductive MWCNTs multilayer on a routine PP separator with polyethyleneimine(PEI) polymer. Owing to "proton-sponge"-based PEI feature with the abundant amino/imine groups and branched structures, the PMS separator can provide strong affinity to immobilize the negatively charged polysulfides via electrostatic interaction. Simultaneously,incorporated with the conductive MWCNTs multilayers for the electron transportation, the Li-S cells assembled with PMS separators achieve exceptional high delivery capacity, good rate performance(~550 m Ah g-1 at a current density of 9 A g-1), and stable cycling retention(retention of84.5% at a current density of 1 A g-1) even over 120 cycles, especially in the case of high-loading sulfur cathode(80 wt% of S content). This multifunctional separator with dual-structural architectures via self-assembly LBS method paves new avenues to develop high-performance Li-S batteries.展开更多
The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can significantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduction reaction...The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can significantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduction reaction(ORR)compared to the disordered atomic structures in ordinary solid-solution alloy NPs.Accordingly,through a facile and scalable synthetic method,a series of carbon-supported ultrafine Pt_3Co_(x)Mn_(1-x)ternary INPs are prepared in this work,which possess the"skin-like"ultrathin Pt shells,the ordered L1_(2) atomic structure,and the high-even dispersion on supports(L1_(2)-Pt_3Co_(x)Mn_(1-x)/~SPt INPs/C).Electrochemical results present that the composition-optimized L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C exhibits the highest electrocata lytic activity among the series,which are also much better than those of the pristine ultrafine Pt/C.Besides,it also has a greatly enhanced electrochemical stability.In addition,the effects of annealing temperature and time are further investigated.More importantly,such superior ORR electrocatalytic performance of L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C are also well demonstrated in practical fuel cells.Physicochemical characterization analyses further reveal the major origins of the greatly enhanced ORR electrocata lytic performance:the Pt-Co-Mn alloy-induced geometric and ligand effects as well as the extremely high L1_(2) atomic-ordering degree.This work not only successfully develops a highly active and stable ordered ternary intermetallic ORR electrocatalyst,but also elucidates the corresponding"structure-function"relationship,which can be further applied in designing other intermetallic(electro)catalysts.展开更多
Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements ...Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements in electrolyte chemistry need to be coupled with optimized electrode materials and tailored electrolyte/electrode interphases.Herein,this review critically outlines electrolytes’limiting factors,including reduced ionic conductivity,large de-solvation energy,sluggish charge transfer,and slow Li-ion transportation across the electrolyte/electrode interphases,which affect the low-temperature performance of Li-metal batteries.Detailed theoretical derivations that explain the explicit influence of temperature on battery performance are presented to deepen understanding.Emerging improvement strategies from the aspects of electrolyte design and electrolyte/electrode interphase engineering are summarized and rigorously compared.Perspectives on future research are proposed to guide the ongoing exploration for better low-temperature Li-metal batteries.展开更多
Rechargeable aqueous zinc-ion batteries(AZIBs)offer high energy density,low cost,and are environmentally friendly,rendering them potential energy storage devices.However,dendrite growth on the zinc anode and numerous ...Rechargeable aqueous zinc-ion batteries(AZIBs)offer high energy density,low cost,and are environmentally friendly,rendering them potential energy storage devices.However,dendrite growth on the zinc anode and numerous side reac-tions during operation challenge their commercialization.Recent advancements have introduced various materials for the functionalization of zinc anodes.These developments effectively mitigate the performance degradation of zinc anode,enhancing both its cycle stability and the overall performance of AZIBs.Herein,the construction of functionalized zinc anodes is discussed,current materials(including organic,inorganic and their composites)for modified zinc anodes are categorized,and the protective mechanism behind functionalized zinc anodes is analyzed.The study concludes by outlining the characteristics of materials suitable for dendritic-free zinc anode construction and the prospects for future development directions of functionalized zinc anodes in AZIBs.展开更多
Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures....Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures.Herein,a flame-retardant,low-cost and thermally stable long chain phosphate ester based(tributyl phosphate,TBP)electrolyte is reported,which can effectively enhance the cycling stability of highly loaded high-nickel LMBs with high safety through co-solvation strategy.The interfacial compatibility between TBP and electrode is effectively improved using a short-chain ether(glycol dimethyl ether,DME),and a specially competitive solvation structure is further constructed using lithium borate difluorooxalate(LiDFOB)to form the stable and inorganic-rich electrode interphases.Benefiting from the presence of the cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)enriched with LiF and Li_(x)PO_(y)F_(z),the electrolyte demonstrates excellent cycling stability assembled using a 50μm lithium foil anode in combination with a high loading NMC811(15.4 mg cm^(-2))cathode,with 88%capacity retention after 120 cycles.Furthermore,the electrolyte exhibits excellent high-temperature characteristics when used in a 1-Ah pouch cell(N/P=0.26),and higher thermal runaway temperature(238℃)in the ARC(accelerating rate calorimeter)demonstrating high safety.This novel electrolyte adopts long-chain phosphate as the main solvent for the first time,and would provide a new idea for the development of extremely high safety and high-temperature electrolytes.展开更多
Hydrogen peroxide that is produced through the two-electron pathway during the catalysis of oxygen reduction reaction(ORR)is recognized as harmful to the stability of nitrogen-doped carbon and Fe-based nonprecious cat...Hydrogen peroxide that is produced through the two-electron pathway during the catalysis of oxygen reduction reaction(ORR)is recognized as harmful to the stability of nitrogen-doped carbon and Fe-based nonprecious catalyst(Fe-N-C)for fuel cell application.A major remaining scientific question is how fast the removal of these deleterious intermediates can contribute to stability enhancement.Here,we report that the stability of Fe-N-C catalysts is positively correlated with the kinetic constant of hydrogen peroxide decomposition.Modulation of the H_(2)O_(2) decomposition kinetics by applying the frequency factor of the Arrhenius equation from 800 to 30000 s^(-1) for TiO_(2),CeO_(2) and ZrO_(2) reduced the decay rate of Fe-N-C catalysts from 0.151% to ‒0.1% in a 100-hour stability test.Fe-N-C/ZrO_(2) with a frequency factor of 30000 s^(-1) showed a 10% increase in current density during a 100-hour stability test and almost no decay during 15 hours of continuous fuel cell operation at a high potential of 0.7 V.展开更多
The triple bond in N_(2)has an extremely high bond energy and is thus difficult to break.N_(2)is commonly converted into NH3 artificially via the Haber-Bosch process,and NH_(3)can be utilized to produce other nitrogen...The triple bond in N_(2)has an extremely high bond energy and is thus difficult to break.N_(2)is commonly converted into NH3 artificially via the Haber-Bosch process,and NH_(3)can be utilized to produce other nitrogen-containing chemicals.Here,we developed an electron catalyzed method to directly fix N_(2)into azos,by pushing and pulling the electron into and from the aromatic halide with the cyclic voltammetry method.The round-trip journey of electron can successfully weaken the triple bond in N_(2)through the electron pushing-induced aryl radical via a“brick trowel”transition state,and then produce the diazonium ions by pulling the electron out from the diazo radical intermediate.Different azos can be synthesized with this developed electron catalyzed approach.This approach provides a novel concept and practical route for the fixation of N_(2)at atmospheric pressure into chemical products valuable for industrial and commercial applications.展开更多
Lithium metal anode is a promising electrode with high theoretical specific capacity and low electrode potential.However,its unstable interface and low Coulombic efficiency,resulting from the dendritic growth of lithi...Lithium metal anode is a promising electrode with high theoretical specific capacity and low electrode potential.However,its unstable interface and low Coulombic efficiency,resulting from the dendritic growth of lithium,limits its commercial application.PIM-1(PIM:polymer of intrinsic microporosity),which is a polymer with abundant micropores,exhibits high rigidity and flexibility with contorted spirocenters in the backbone,and is an ideal candidate for artificial solid electrolyte interphases(SEI).In this work,a PIM-1 membrane was synthesized and fabricated as a protective membrane on the surface of an electrode to facilitate the uniform flux of Li ions and act as a stable interface for the lithium plating/stripping process.Nodule-like lithium with rounded edges was observed under the PIM-1 membrane.The Li@PIM-1 electrode delivered a high average Coulombic efficiency(99.7%),excellent cyclability(80%capacity retention rate after 600 cycles at 1 C),and superior rate capability(125.3 m Ah g-1 at 10 C).Electrochemical impedance spectrum(EIS)showed that the PIM-1 membrane could lower the diffusion rate of Li+significantly and change the rate-determining step from charge transfer to Li+diffusion.Thus,the PIM-1 membrane is proven to act as an artificial SEI to facilitate uniform and stable deposition of lithium,in favor of obtaining a compact and dense Li-plating pattern.This work extends the application of PIMs in the field of lithium batteries and provides ideas for the construction of artificial SEI.展开更多
A uniform diffusion layer is essential for non-dendritic deposition of lithium in high-density lithium batteries.However,natural pristine solid electrolyte interface(SEI)is always porous and inhomogeneous because of r...A uniform diffusion layer is essential for non-dendritic deposition of lithium in high-density lithium batteries.However,natural pristine solid electrolyte interface(SEI)is always porous and inhomogeneous because of repeated breakdown and repair cycles,whereas ideal materials with excellent mechanical property for artificial SEIs remain a challenge.Herein,a robust and stable interface is achieved by spinning soft polymer associated with few MoO_(3) into fibers,and thus mechanical property of fibers other than materials determines mechanical performance of the interface which can be optimized by adjusting parameters.Furthermore,lithium deposited underneath the layer is enabled by constructing an optimal resistance to make the membrane serve as an artificial SEI rather than lithium host.As a result,dendritefree lithium was observed underneath the membrane,and stable interface for long-term cycling was also indicated by EIS measurements.The lithium iron phosphate(LiFePO_(4))full-cell with coated electrode demonstrated an initial capacity of 155.2 m Ah g^(-1),and 80%of its original capacity was retained after 500 cycles at 2.0℃ without any additive in carbonate-based electrolyte.展开更多
LiFePO_(4)cathode was successfully co-coated by ZrO_(2)and N-doped carbon layer based on the coprecipitation of Zr species and polydopamine on the LiFePO_(4)surfaces.The mutual promotion between the hydrolyzation of Z...LiFePO_(4)cathode was successfully co-coated by ZrO_(2)and N-doped carbon layer based on the coprecipitation of Zr species and polydopamine on the LiFePO_(4)surfaces.The mutual promotion between the hydrolyzation of ZrO_(2)precursor and the self-polymerization of dopamine was realized in the one-step synthesis.After being used in the coin battery as cathode material,the ZrO_(2)and N-doped carbon co-coated LiFePO_(4)displayed improved cycling stability(97.0%retention at 0.2 C after 200 cycles)and enhanced rate performance(130.7 mAh·g^(−1) at 1 C)due to its higher electrochemical reactivity and reversibility compared with those of commercial LiFePO_(4).展开更多
Spinel oxides,with the formula AB_(2)O_(4)(A and B represent metal ions)perform superior electrocatalytic characteristic when A and B are transition metals like Co,Fe,Mn,etc.Abundant researches have been attached to t...Spinel oxides,with the formula AB_(2)O_(4)(A and B represent metal ions)perform superior electrocatalytic characteristic when A and B are transition metals like Co,Fe,Mn,etc.Abundant researches have been attached to the structure designments while methods are often energy-intensive and inefficient.Here,we devised a universal strategy to achieve rapid synthesis of nanocrystalline spinel materials with multiple components(Co_(3)O_(4),Mn_(3)O_(4),CoMn_(2)O_(4)and CoFe_(2)O_(4)are as examples),where phase formation is within 15 s.Under the Joule-heating shock,a crack-break process of microcosmic phase transformation is observed by in-situ transmission electron microscopy.The half-wave potential values of Co_(3)O_(4)-JH,Mn_(3)O_(4)-JH,CoMn_(2)O_(4)-JH and CoFe_(2)O_(4)-JH in the electrocatalytic oxygen reduction reaction were 0.77,0.78,0.79 and 0.76,respectively.This suggests that the Joule heating is a fast and efficient method for the preparation of spinel oxide electrocatalysts.展开更多
Chloroprene is a monomer widely used in the production of neoprene,and 1-hydroxy-2-butanone(1H2B)is one of the metabolites of chloroprene in urine,which can place a significant impact on human health by disrupting the...Chloroprene is a monomer widely used in the production of neoprene,and 1-hydroxy-2-butanone(1H2B)is one of the metabolites of chloroprene in urine,which can place a significant impact on human health by disrupting the normal structure and function of DNA.Herein,a three-dimensional Zn-based coordination polymer(1)and a two-dimensional Cd-based coordination polymer(2)were synthesized with mixed ligands of 2,5-furandicarboxylic acid(H_(2)FDA)and 1,2,4-triazole(Htrz)and fully characterized.2 exhibits excellent stability and superior sensing performance for 1H2B with fast response within 15 s,good recyclability and a detection limit of 9.24μM.In addition,2 demonstrates good selectivity in presence of main coexisting compounds in urine.In-depth in-vestigations of the sensing mechanism revealed that the luminescence sensing is based on the competitive ab-sorption and photoelectron transfer processes.展开更多
Hydrogen,a green and sustainable energy source characterized by its abundance,zero emission,and high-volumetric energy density,is widely recognized as the fuel of the future and a crucial driver of the global energy t...Hydrogen,a green and sustainable energy source characterized by its abundance,zero emission,and high-volumetric energy density,is widely recognized as the fuel of the future and a crucial driver of the global energy transition.Proton exchange membrane fuel cells(PEMFCs),renowned for their high energy conversion efficiency,environmental compatibility,and low noise,have become pivotal in hydrogen energy applications[1,2].As the demand for clean energy increases across various application scenarios,expectations for fuel cells to achieve high output power density,simplified thermal management,and improved tolerance to impurity gases are growing.A promising solution is to increase the operating temperature to develop medium-temperature PEMFCs(MT PEMFCs),which bridges the gap between low-temperature fuel cells and high-temperature phosphoric acid fuel cells.This approach significantly enhances catalyst activity and theoretically improves electrochemical reaction kinetics[3].Elevated temperatures also reduce heat rejection,leading to simplified thermal management systems,and enhance the catalyst’s resistance to gas impurities such as carbon monoxide,thereby broadening the range of usable hydrogen sources[3].展开更多
Silver molybdate(Ag_(6)Mo_(10)O_(33))exhibits excellent catalytic properties and photocatalytic degradation owing to its unique chemical and structural characteristics,but its prospective applications in electrochemis...Silver molybdate(Ag_(6)Mo_(10)O_(33))exhibits excellent catalytic properties and photocatalytic degradation owing to its unique chemical and structural characteristics,but its prospective applications in electrochemistry energy storage have not received sufficient attention.Herein,the Ag_(6)Mo_(10)O_(33) meso/nanowires with superior morphological characteristics are fabricated employing a high-efficient microwave irradiation method.Furthermore,the novel synthesizing mechanism of ultralong Ag_(6)Mo_(10)O_(33) mesowires is also proved to be a“self-assembly-dissolution-recrystallization-Ostwald-ripening”process,by exploring through the parallel experiments on the dramatic alterations in topology and size of Ag_(6)Mo_(10)O_(33) at continuous reaction time.Additionally,the properties of the ultralong uniform Ag_(6)Mo_(10)O_(33) mesowires for the sodium storage are investigated via cyclic voltammetry,electrochemical impedance spectroscopy and galvanostatic charge-discharge.Notably,these as-obtained Ag_(6)Mo_(10)O_(33) mesowires exhibit an outstanding initial capacity(1587.9 mAh·g^(-1)),a remarkable specific capacity for the second cycle(817.9 mAh·g^(-1)),and an excellent reversible capacity(551.5 mAh·g^(-1) after 30 cycles).The superior electrochemical properties of the nanoscaled silver molybdate are ascribed to the lower charge transfer resistance due to the microstructure of the smallest size Ag_(6)Mo_(10)O_(33) nanosheets that exhibit a thickness of around 5 nm,which can provide a great contact with the electrolyte,facilitating the rapid diffusion of sodium ions at the electrode/electrolyte interface and the rapid transport of sodium ions within the electrode materials.Thus,the proposed synthetic strategy and achieved deep insights will stimulate the development of Ag_(6)Mo_(10)O_(33) for high-safety and long-life sodium ion batteries.展开更多
基金supported by the National Key Research and Development Program of China(No.2020YFB1506002,2019YFB1504503,2016YFB0101202)National 973 Program of China(No.2012CB215501)National Natural Science Foundation of China(No.52021004,22022502(2021),21822803(2019),21576031(2016),51272297(2013),20936008(2010),20676156(2007),20376088(2004),20176066(2002),29976047(2000)).
文摘Two major challenges,high cost and short lifespan,have been hindering the commercialization process of lowtemperature fuel cells.Professor Wei's group has been focusing on decreasing cathode Pt loadings without losses of activity and durability,and their research advances in this area over the past three decades are briefly reviewed herein.Regarding the Pt-based catalysts and the low Pt usage,they have firstly tried to clarify the degradation mechanism of Pt/C catalysts,and then demonstrated that the activity and stability could be improved by three strategies:regulating the nanostructures of the active sites,enhancing the effects of support materials,and optimizing structures of the three-phase boundary.For Pt-free catalysts,especialiy carbon-based ones,several strategies that they proposed to enhance the activity of nitrogen-/heteroatom-doped carbon catalysts are firstly presented.Then,an indepth understanding of the degradation mechanism for carbon-based catalysts is discussed,and followed by the corresponding stability enhancement strategies.Also,the carbon-based electrode at the micrometer-scale,faces the challenges such as low active-site density,thick catalytic layer,and the effect of hydrogen peroxide,which require rational structure design for the integral cathodic electrode.This review finally gives a brief conclusion and outlook about the low cost and long lifespan of cathodic oxygen reduction catalysts.
基金supported by the China National Funds for Distinguished Young Scientists(21925503)the National Natural Science Foundation of China(21835004)the Jilin Scientific and Technological Development Program(20220301018GX)。
文摘Cobalt-free,nickel-rich LiNi_(1-x)Al_(x)O_(2)(x≤0.1)is an attractive cathode material because of high energy density and low cost but suffers from severe structural degradation and poor rate performance.In this study,we propose a molten salt-assisted synthesis in combination with a Li-refeeding induced aluminum segregation strategy to prepare Li_(5)AlO_(4)-coated single-crystalline slightly Li-rich Li_(1.04)Ni_(0.92)Al_(0.04)O_(2).The symbiotic formation of Li_(5)AlO_(4)from reaction between molten lithium hydroxide and doped aluminum in the bulk ensures a high lattice matching between the Ni-rich oxide and the homogenous conductive Li_(5)AlO_(4)that permits high Li^(+)conductivity.Benefiting from mitigated undesirable side reactions and phase evolution,the Li_(5)AlO_(4)-coated single-crystalline Li_(1.04)Ni_(0.92)Al_(0.04)O_(2)delivers a high specific capacity of220.2 mA h g^(-1)at 0.1 C and considerable rate capability(182.5 mA h g^(-1)at 10 C).Besides,superior capacity retention of 90.8%is obtained at 1/3 C after 100 cycles in a 498.1 mA h pouch full cell.Furthermore,the particulate morphology of Li_(1.04)Ni_(0.92)Al_(0.04)O_(2)remains intact after cycling at a cutoff voltage of 4.3 V,whereas slightly Li-deficient Li_(0.98)Ni_(0.97)Al_(0.05)O_(2)features intragranular cracks and irreversible lattice distortion.The results highlight the value of molten salt-assisted synthesis and Li-refeeding induced elemental segregation strategy to upgrade Ni-based layered oxide cathode materials for advanced Li-ion batteries.
基金supported by the National Natural Science Foundation of China(Grant Nos.52072322,22209137,51604250)the Department of Science and Technology of Sichuan Province(CN)(GrantNos.2022YFG0294,23GJHZ0147,23ZDYF0262)Production-Education Integration Demonstration Project of Sichuan Province"Photovoltaic Industry Production-Education Integration Comprehensive Demonstration Base of Sichuan Province"(Sichuan Financial Education[2022]No.106.n)。
文摘Sodium-based storage devices based on conversion-type metal sulfide anodes have attracted great atten-tion due to their multivalent ion redox reaction ability.However,they also suffer from sodium polysul-fides(NaPSs)shuttling problems during the sluggish Na^(+) redox process,leading to"voltage failure"and rapid capacity decay.Herein,a metal cobalt-doping vanadium disulfide(Co-VS_(2))is proposed to simulta-neously accelerate the electrochemical reaction of VS_(2) and enhance the bidirectional redox of soluble NaPSs.It is found that the strong adsorption of NaPSs by V-Co alloy nanoparticles formed in situ during the conversion reaction of Co-VS_(2) can effectively inhibit the dissolution and shuttle of NaPSs,and ther-modynamically reduce the formation energy barrier of the reaction path to effectively drive the complete conversion reaction,while the metal transition of Co elements enhances reconversion kinetics to achieve high reversibility.Moreover,Co-VS_(2) also produce abundant sulfur vacancies and unsaturated sulfur edge defects,significantly improve ionic/electron diffusion kinetics.Therefore,the Co-VS_(2) anode exhibits ultrahigh rate capability(562 mA h g^(-1) at 5 A g^(-1)),high initial coulombic efficiency(~90%)and 12,000 ultralong cycle life with capacity retention of 90%in sodium-ion batteries(SIBs),as well as impressive energy/power density(118 Wh kg^(-1)/31,250 W kg^(-1))and over 10.000 stable cycles in sodium-ion hybrid capacitors(SIHCs).Moreover,the pouch cell-type SIHC displays a high-energy density of 102 Wh kg^(-1) and exceed 600 stable cycles.This work deepens the understanding of the electrochemical reaction mechanism of conversion-type metal sulfide anodes and provides a valuable solution to the shuttlingofNaPSs inSIBsandSIHCs.
基金supported by the National Key R&D Program of China(2021YFB2500300)the National Natural Science Foundation of China(22372083,52201259)+1 种基金the Natural Science Foundation of Tianjin(22JCZDJC00380)Young Elite Scientist Sponsorship Program by CAST。
文摘Charge transfer at the liquid(electrolyte)-solid(metal)interfaces is of fundamental importance to metal electrochemical deposition that further determines the reversibility and kinetics of energy-dense rechargeable metal batteries(RMBs).We demonstrate the fast charge transfer at the electrolyte-metal interfaces for lithium metal by designing and synthesizing electrolytes with chiral solvents:R(or S)-1,2-dimethoxy pro pane(R-DMP or S-DMP)and R(or S)-4-methyl-1,3-dioxolane(R-MDOL or S-MDOL).The chiral-induced spin selectivity is considered to produce spin-polarized metal surfaces,enabling the improvement in charge transfer rate and efficiency.The deposited Li metal in chiral electrolytes shows smooth and uniform morphologies,as well as high initial(>95%)and average(~99.2%)Coulombic efficiency for Li metal stripping/plating process,thus prolonging the life-span of batteries using thin lithium anode(50μm)to 400 cycles till 80%capacity retention.This work provides a distinct approach to regulate metal deposition beyond the limitation of ion de-solvation.
基金supported by the National Natural Science Foundation of China(No.51274075)the National Environmental Technology Special Project(No.201009028)Guangdong Province-department University-industry Collaboration Project(Grant No.2012B091100315)
文摘With the rapid development of consumer electronics and electric vehicles(EV), a large number of spent lithium-ion batteries(LIBs) have been generated worldwide. Thus, effective recycling technologies to recapture a significant amount of valuable metals contained in spent LIBs are highly desirable to prevent the environmental pollution and resource depletion. In this work, a novel recycling technology to regenerate a LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2 cathode material from spent LIBs with different cathode chemistries has been developed. By dismantling, crushing,leaching and impurity removing, the LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2(selected as an example of LiNi_xCo_yMn_(1-x-y)O_2) powder can be directly prepared from the purified leaching solution via co-precipitation followed by solid-state synthesis. For comparison purposes, a fresh-synthesized sample with the same composition has also been prepared using the commercial raw materials via the same method. X-ray diffraction(XRD), scanning electron microscopy(SEM) and electrochemical measurements have been carried out to characterize these samples. The electrochemical test result suggests that the re-synthesized sample delivers cycle performance and low rate capability which are comparable to those of the freshsynthesized sample. This novel recycling technique can be of great value to the regeneration of a pure and marketable LiNi_xCo_yMn_(1-x-y)O_2 cathode material with low secondary pollution.
基金financially supported by the National Natural Science Foundation of China(51971080)the Natural Science Foundation of Guangdong Province,China(2018A030313182)+1 种基金Shenzhen Bureau of Science,Technology and Innovation Commission(JCYJ20170811154527927)the Opening Project of State Key Laboratory of Advanced Chemical Power Sources。
文摘Lithium-sulfur battery is desirable for the future potential electrochemical energy storage device with advantages of high theoretical energy density,low cost and environmental friendliness.However,some natural hindrances,particularly fast capacity degradation resulting from the migration of dissolved polysulfide intermediates,remain to be significant challenges prior to the practical applications.In this work,a composite interlayer of carbon nanofibers(CNFs)which are enriched by Co-based metal organic frameworks(ZIF-67)growth in-situ is exploited.Notably,physical blocking and chemical trapping abilities are obtained synergistically from the ZIF/CNFs interlayer,which enables to restrain the dissolution of polysulfides and alleviate shuttle effect.Moreover,the three-dimensional fiber networks provide an interconnected conductive framework between each ZIF microreactor to promote fast electron transfer during cycling,thus contributing to excellent rate and cycling performance.As a result,Li-S cells with ZIF/CNFs interlayer show a high specific capacity of 1334 mAh g^(-1) at 1 C with an excellent cycling stability over 300 cycles.Besides,this scalable and affordable electrospinning fabrication method provides a promising approach for the design of MOFs-derived carbon materials for high performance Li-S batteries.
基金support of the National Natural Science Foundation of China (51671135, 21875141)support of the Program of Shanghai Subject Chief Scientist (17XD1403000)+2 种基金Innovation Program of Shanghai Municipal Education Commission (2019-01-07-00-07-E00015)Shanghai Outstanding Academic Leaders Plan, Shanghai Pujiang Program (18PJ1409000)the Opening Project of State Key Laboratory of Advanced Chemical Power Sources (SKL-ACPS-C-23)
文摘Lithium–sulfur(Li-S) battery is considered as one of the most promising candidates for future portable electronics and electric vehicles due to high energy density and potentially low cost. However, the severe polysulfides shuttling in Li-S battery always causes low Coulombic efficiency, capacity fading, and hindering its practical commercialization. Herein, a dualfunctional PEI@MWCNTs-CB/MWCNTs/PP(briefly denoted as PMS)separator is assembled through Langmuir–Blodgett–Scooping(LBS) technique for improvement of Li-S battery performance, that is, rational integrating conductive MWCNTs multilayer on a routine PP separator with polyethyleneimine(PEI) polymer. Owing to "proton-sponge"-based PEI feature with the abundant amino/imine groups and branched structures, the PMS separator can provide strong affinity to immobilize the negatively charged polysulfides via electrostatic interaction. Simultaneously,incorporated with the conductive MWCNTs multilayers for the electron transportation, the Li-S cells assembled with PMS separators achieve exceptional high delivery capacity, good rate performance(~550 m Ah g-1 at a current density of 9 A g-1), and stable cycling retention(retention of84.5% at a current density of 1 A g-1) even over 120 cycles, especially in the case of high-loading sulfur cathode(80 wt% of S content). This multifunctional separator with dual-structural architectures via self-assembly LBS method paves new avenues to develop high-performance Li-S batteries.
基金supported by the National Key Research and Development Program of China(2021YFB4001301)the Science and Technology Commission of Shanghai Municipality(21DZ1208600)the Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(SL2021ZD105)。
文摘The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can significantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduction reaction(ORR)compared to the disordered atomic structures in ordinary solid-solution alloy NPs.Accordingly,through a facile and scalable synthetic method,a series of carbon-supported ultrafine Pt_3Co_(x)Mn_(1-x)ternary INPs are prepared in this work,which possess the"skin-like"ultrathin Pt shells,the ordered L1_(2) atomic structure,and the high-even dispersion on supports(L1_(2)-Pt_3Co_(x)Mn_(1-x)/~SPt INPs/C).Electrochemical results present that the composition-optimized L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C exhibits the highest electrocata lytic activity among the series,which are also much better than those of the pristine ultrafine Pt/C.Besides,it also has a greatly enhanced electrochemical stability.In addition,the effects of annealing temperature and time are further investigated.More importantly,such superior ORR electrocatalytic performance of L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C are also well demonstrated in practical fuel cells.Physicochemical characterization analyses further reveal the major origins of the greatly enhanced ORR electrocata lytic performance:the Pt-Co-Mn alloy-induced geometric and ligand effects as well as the extremely high L1_(2) atomic-ordering degree.This work not only successfully develops a highly active and stable ordered ternary intermetallic ORR electrocatalyst,but also elucidates the corresponding"structure-function"relationship,which can be further applied in designing other intermetallic(electro)catalysts.
基金The work described in this paper was fully supported by a Grant from the City University of Hong Kong(Project No.9610641).
文摘Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements in electrolyte chemistry need to be coupled with optimized electrode materials and tailored electrolyte/electrode interphases.Herein,this review critically outlines electrolytes’limiting factors,including reduced ionic conductivity,large de-solvation energy,sluggish charge transfer,and slow Li-ion transportation across the electrolyte/electrode interphases,which affect the low-temperature performance of Li-metal batteries.Detailed theoretical derivations that explain the explicit influence of temperature on battery performance are presented to deepen understanding.Emerging improvement strategies from the aspects of electrolyte design and electrolyte/electrode interphase engineering are summarized and rigorously compared.Perspectives on future research are proposed to guide the ongoing exploration for better low-temperature Li-metal batteries.
基金Hebei Natural Science Fund for Distinguished Young Scholar,Grant/Award Number:E2019209433Natural Science Foundation of Hebei Province,Grant/Award Number:E2022209158+2 种基金National Natural Science Foundation of China,Grant/Award Number:52302223National Research Foundation of Korea,Grant/Award Number:NRF-2019R1A2C2090443Technology Innovation Program(Ministry of Trade,Industry&Energy,Korea),Grant/Award Number:20013621。
文摘Rechargeable aqueous zinc-ion batteries(AZIBs)offer high energy density,low cost,and are environmentally friendly,rendering them potential energy storage devices.However,dendrite growth on the zinc anode and numerous side reac-tions during operation challenge their commercialization.Recent advancements have introduced various materials for the functionalization of zinc anodes.These developments effectively mitigate the performance degradation of zinc anode,enhancing both its cycle stability and the overall performance of AZIBs.Herein,the construction of functionalized zinc anodes is discussed,current materials(including organic,inorganic and their composites)for modified zinc anodes are categorized,and the protective mechanism behind functionalized zinc anodes is analyzed.The study concludes by outlining the characteristics of materials suitable for dendritic-free zinc anode construction and the prospects for future development directions of functionalized zinc anodes in AZIBs.
基金supported by the National Natural Science Foundation of China (grant No.52072322)the Department of Science and Technology of Sichuan Province (CN) (grant no.23GJHZ0147,23ZDYF0262,2022YFG0294)Research and Innovation Fund for Graduate Students of Southwest Petroleum University (No.:2022KYCX111)。
文摘Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures.Herein,a flame-retardant,low-cost and thermally stable long chain phosphate ester based(tributyl phosphate,TBP)electrolyte is reported,which can effectively enhance the cycling stability of highly loaded high-nickel LMBs with high safety through co-solvation strategy.The interfacial compatibility between TBP and electrode is effectively improved using a short-chain ether(glycol dimethyl ether,DME),and a specially competitive solvation structure is further constructed using lithium borate difluorooxalate(LiDFOB)to form the stable and inorganic-rich electrode interphases.Benefiting from the presence of the cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)enriched with LiF and Li_(x)PO_(y)F_(z),the electrolyte demonstrates excellent cycling stability assembled using a 50μm lithium foil anode in combination with a high loading NMC811(15.4 mg cm^(-2))cathode,with 88%capacity retention after 120 cycles.Furthermore,the electrolyte exhibits excellent high-temperature characteristics when used in a 1-Ah pouch cell(N/P=0.26),and higher thermal runaway temperature(238℃)in the ARC(accelerating rate calorimeter)demonstrating high safety.This novel electrolyte adopts long-chain phosphate as the main solvent for the first time,and would provide a new idea for the development of extremely high safety and high-temperature electrolytes.
基金financially supported by the National Key Research and Development Program of China(2021YFA1502000)the National Natural Science Foundation of China(22022502 and 22179012)Natural Science Foundation of Chongqing,China(CSTB2023NSCQLZX0084).
文摘Hydrogen peroxide that is produced through the two-electron pathway during the catalysis of oxygen reduction reaction(ORR)is recognized as harmful to the stability of nitrogen-doped carbon and Fe-based nonprecious catalyst(Fe-N-C)for fuel cell application.A major remaining scientific question is how fast the removal of these deleterious intermediates can contribute to stability enhancement.Here,we report that the stability of Fe-N-C catalysts is positively correlated with the kinetic constant of hydrogen peroxide decomposition.Modulation of the H_(2)O_(2) decomposition kinetics by applying the frequency factor of the Arrhenius equation from 800 to 30000 s^(-1) for TiO_(2),CeO_(2) and ZrO_(2) reduced the decay rate of Fe-N-C catalysts from 0.151% to ‒0.1% in a 100-hour stability test.Fe-N-C/ZrO_(2) with a frequency factor of 30000 s^(-1) showed a 10% increase in current density during a 100-hour stability test and almost no decay during 15 hours of continuous fuel cell operation at a high potential of 0.7 V.
文摘The triple bond in N_(2)has an extremely high bond energy and is thus difficult to break.N_(2)is commonly converted into NH3 artificially via the Haber-Bosch process,and NH_(3)can be utilized to produce other nitrogen-containing chemicals.Here,we developed an electron catalyzed method to directly fix N_(2)into azos,by pushing and pulling the electron into and from the aromatic halide with the cyclic voltammetry method.The round-trip journey of electron can successfully weaken the triple bond in N_(2)through the electron pushing-induced aryl radical via a“brick trowel”transition state,and then produce the diazonium ions by pulling the electron out from the diazo radical intermediate.Different azos can be synthesized with this developed electron catalyzed approach.This approach provides a novel concept and practical route for the fixation of N_(2)at atmospheric pressure into chemical products valuable for industrial and commercial applications.
基金supported by the Opening Project(SKLACPS-C-21)of the State Key Laboratory of Advanced Chemical Power Source,Guizhou Meiling Power Sources Co.,Ltd.the Program for Innovative and Entrepreneurial team in Zhuhai(ZH01110405160007PWC).
文摘Lithium metal anode is a promising electrode with high theoretical specific capacity and low electrode potential.However,its unstable interface and low Coulombic efficiency,resulting from the dendritic growth of lithium,limits its commercial application.PIM-1(PIM:polymer of intrinsic microporosity),which is a polymer with abundant micropores,exhibits high rigidity and flexibility with contorted spirocenters in the backbone,and is an ideal candidate for artificial solid electrolyte interphases(SEI).In this work,a PIM-1 membrane was synthesized and fabricated as a protective membrane on the surface of an electrode to facilitate the uniform flux of Li ions and act as a stable interface for the lithium plating/stripping process.Nodule-like lithium with rounded edges was observed under the PIM-1 membrane.The Li@PIM-1 electrode delivered a high average Coulombic efficiency(99.7%),excellent cyclability(80%capacity retention rate after 600 cycles at 1 C),and superior rate capability(125.3 m Ah g-1 at 10 C).Electrochemical impedance spectrum(EIS)showed that the PIM-1 membrane could lower the diffusion rate of Li+significantly and change the rate-determining step from charge transfer to Li+diffusion.Thus,the PIM-1 membrane is proven to act as an artificial SEI to facilitate uniform and stable deposition of lithium,in favor of obtaining a compact and dense Li-plating pattern.This work extends the application of PIMs in the field of lithium batteries and provides ideas for the construction of artificial SEI.
基金supported by the Opening Project(No.SKLACPS-C-21)of the State Key Laboratory of Advanced Chemical Power Source,Guizhou Meiling Power Sources Co.,Ltd.the Program for Innovative and Entrepreneurial team in Zhuhai(ZH01110405160007PWC)。
文摘A uniform diffusion layer is essential for non-dendritic deposition of lithium in high-density lithium batteries.However,natural pristine solid electrolyte interface(SEI)is always porous and inhomogeneous because of repeated breakdown and repair cycles,whereas ideal materials with excellent mechanical property for artificial SEIs remain a challenge.Herein,a robust and stable interface is achieved by spinning soft polymer associated with few MoO_(3) into fibers,and thus mechanical property of fibers other than materials determines mechanical performance of the interface which can be optimized by adjusting parameters.Furthermore,lithium deposited underneath the layer is enabled by constructing an optimal resistance to make the membrane serve as an artificial SEI rather than lithium host.As a result,dendritefree lithium was observed underneath the membrane,and stable interface for long-term cycling was also indicated by EIS measurements.The lithium iron phosphate(LiFePO_(4))full-cell with coated electrode demonstrated an initial capacity of 155.2 m Ah g^(-1),and 80%of its original capacity was retained after 500 cycles at 2.0℃ without any additive in carbonate-based electrolyte.
基金by the National Key R&D Program of China(No.2018YFC1902200)。
文摘LiFePO_(4)cathode was successfully co-coated by ZrO_(2)and N-doped carbon layer based on the coprecipitation of Zr species and polydopamine on the LiFePO_(4)surfaces.The mutual promotion between the hydrolyzation of ZrO_(2)precursor and the self-polymerization of dopamine was realized in the one-step synthesis.After being used in the coin battery as cathode material,the ZrO_(2)and N-doped carbon co-coated LiFePO_(4)displayed improved cycling stability(97.0%retention at 0.2 C after 200 cycles)and enhanced rate performance(130.7 mAh·g^(−1) at 1 C)due to its higher electrochemical reactivity and reversibility compared with those of commercial LiFePO_(4).
基金supported by the National Programs for NanoKey Project(No.2022YFA1504002)the National Natural Science Foundation of China(Nos.22121005,22020102002,and 21835004)the Fundamental Research Funds for the Central Universities,and Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)。
文摘Spinel oxides,with the formula AB_(2)O_(4)(A and B represent metal ions)perform superior electrocatalytic characteristic when A and B are transition metals like Co,Fe,Mn,etc.Abundant researches have been attached to the structure designments while methods are often energy-intensive and inefficient.Here,we devised a universal strategy to achieve rapid synthesis of nanocrystalline spinel materials with multiple components(Co_(3)O_(4),Mn_(3)O_(4),CoMn_(2)O_(4)and CoFe_(2)O_(4)are as examples),where phase formation is within 15 s.Under the Joule-heating shock,a crack-break process of microcosmic phase transformation is observed by in-situ transmission electron microscopy.The half-wave potential values of Co_(3)O_(4)-JH,Mn_(3)O_(4)-JH,CoMn_(2)O_(4)-JH and CoFe_(2)O_(4)-JH in the electrocatalytic oxygen reduction reaction were 0.77,0.78,0.79 and 0.76,respectively.This suggests that the Joule heating is a fast and efficient method for the preparation of spinel oxide electrocatalysts.
基金supported by the National Natural Science Foundation of China(92156002,22261132509 and 21931004).
文摘Chloroprene is a monomer widely used in the production of neoprene,and 1-hydroxy-2-butanone(1H2B)is one of the metabolites of chloroprene in urine,which can place a significant impact on human health by disrupting the normal structure and function of DNA.Herein,a three-dimensional Zn-based coordination polymer(1)and a two-dimensional Cd-based coordination polymer(2)were synthesized with mixed ligands of 2,5-furandicarboxylic acid(H_(2)FDA)and 1,2,4-triazole(Htrz)and fully characterized.2 exhibits excellent stability and superior sensing performance for 1H2B with fast response within 15 s,good recyclability and a detection limit of 9.24μM.In addition,2 demonstrates good selectivity in presence of main coexisting compounds in urine.In-depth in-vestigations of the sensing mechanism revealed that the luminescence sensing is based on the competitive ab-sorption and photoelectron transfer processes.
文摘Hydrogen,a green and sustainable energy source characterized by its abundance,zero emission,and high-volumetric energy density,is widely recognized as the fuel of the future and a crucial driver of the global energy transition.Proton exchange membrane fuel cells(PEMFCs),renowned for their high energy conversion efficiency,environmental compatibility,and low noise,have become pivotal in hydrogen energy applications[1,2].As the demand for clean energy increases across various application scenarios,expectations for fuel cells to achieve high output power density,simplified thermal management,and improved tolerance to impurity gases are growing.A promising solution is to increase the operating temperature to develop medium-temperature PEMFCs(MT PEMFCs),which bridges the gap between low-temperature fuel cells and high-temperature phosphoric acid fuel cells.This approach significantly enhances catalyst activity and theoretically improves electrochemical reaction kinetics[3].Elevated temperatures also reduce heat rejection,leading to simplified thermal management systems,and enhance the catalyst’s resistance to gas impurities such as carbon monoxide,thereby broadening the range of usable hydrogen sources[3].
基金financially supported by the National Natural Science Foundation of China(No.22379103)the Science and Technology Projects of Suzhou City(No.SYC2022043)+3 种基金the Qing Lan Project of Jiangsu Province(2022)Open Project of State Key Laboratory of Inorganic Synthesis and Preparative Chemistry(No.2025-17)Hubei Key Laboratory of Energy Storage and Power Battery(Hubei University of Automotive Technology)(No.ZDK22023B01)the Joint Funds of Advanced Functional Membrane Materials for the Natural Science Foundation of Anhui Province of China(No.2408055UM003).
文摘Silver molybdate(Ag_(6)Mo_(10)O_(33))exhibits excellent catalytic properties and photocatalytic degradation owing to its unique chemical and structural characteristics,but its prospective applications in electrochemistry energy storage have not received sufficient attention.Herein,the Ag_(6)Mo_(10)O_(33) meso/nanowires with superior morphological characteristics are fabricated employing a high-efficient microwave irradiation method.Furthermore,the novel synthesizing mechanism of ultralong Ag_(6)Mo_(10)O_(33) mesowires is also proved to be a“self-assembly-dissolution-recrystallization-Ostwald-ripening”process,by exploring through the parallel experiments on the dramatic alterations in topology and size of Ag_(6)Mo_(10)O_(33) at continuous reaction time.Additionally,the properties of the ultralong uniform Ag_(6)Mo_(10)O_(33) mesowires for the sodium storage are investigated via cyclic voltammetry,electrochemical impedance spectroscopy and galvanostatic charge-discharge.Notably,these as-obtained Ag_(6)Mo_(10)O_(33) mesowires exhibit an outstanding initial capacity(1587.9 mAh·g^(-1)),a remarkable specific capacity for the second cycle(817.9 mAh·g^(-1)),and an excellent reversible capacity(551.5 mAh·g^(-1) after 30 cycles).The superior electrochemical properties of the nanoscaled silver molybdate are ascribed to the lower charge transfer resistance due to the microstructure of the smallest size Ag_(6)Mo_(10)O_(33) nanosheets that exhibit a thickness of around 5 nm,which can provide a great contact with the electrolyte,facilitating the rapid diffusion of sodium ions at the electrode/electrolyte interface and the rapid transport of sodium ions within the electrode materials.Thus,the proposed synthetic strategy and achieved deep insights will stimulate the development of Ag_(6)Mo_(10)O_(33) for high-safety and long-life sodium ion batteries.
