Water electrolysis is a promising technology to produce hydrogen but it was severely restricted by the slow oxygen evolution reaction(OER).Herein,we firstly reported an advanced electrocatalyst of MOF-derived hollow Z...Water electrolysis is a promising technology to produce hydrogen but it was severely restricted by the slow oxygen evolution reaction(OER).Herein,we firstly reported an advanced electrocatalyst of MOF-derived hollow Zn-Co-Ni sulfides(ZnS@Co_(9)S_(8)@Ni_(3)S_(2)-1/2,abbreviated as ZCNS-1/2)nanosword arrays(NSAs)with remarkable hydrogen evolution reaction(HER),OER and corresponding water electrolysis performance.To reach a current density of 10 mA cm^(-2),the cell voltage of assembled ZCNS-1/2//ZCNS-1/2 for urea electrolysis(1.314 V)is 208 mV lower than that for water electrolysis(1.522 V)and stably catalyzed for over 15 h,substantially outperforming the most reported water and urea electrolysis electrocatalysts.Density functional theory calculations and experimental result clearly reveal that the properties of large electrochemical active surface area(ECSA)caused by hollow NSAs and fast charge transfer resulted from the Co_(9)S_(8)@Ni_(3)S_(2) heterostructure endow the ZCNS-1/2 electrode with an enhanced electrocatalytic performance.展开更多
Lithium-sulfur(Li-S)batteries have been recognized as one of the most promising candidates for nextgeneration portable electronic devices,owing to their extremely high energy density and low cost.However,the dissoluti...Lithium-sulfur(Li-S)batteries have been recognized as one of the most promising candidates for nextgeneration portable electronic devices,owing to their extremely high energy density and low cost.However,the dissolution of lithium polysulfides(LiPSs)and consequent"shuttle effect"seriously hinder the practical deployment of Li-S batteries.Herein,multi-metal oxide nanorods named attapulgite are proposed as multifunctional ionic sieve to immobilize LiPSs and further promote the regulation of LiPSs.Attapulgite,consisting of Al,Mg,Fe,Si and O ions,possesses more polar sites to immobilize LiPSs in comparison with single metal oxides.In addition,the catalytic nature(Fe ions)of attapulgite avails the LiPSs conversion reaction,which is further confirmed by the linear sweep voltammetry and electrochemical impedance spectroscopy.Benefited from the synergistic effect of multi-metal oxide and conductive carbon,the Li-S battery with the modified separator delivers remarkable discharge capacities of 1059.4 mAh g-1 and 792.5 mAh g-1 for the first and 200th cycle at 0.5 C,respectively.The work presents an effective way to improve the electrochemical performance of Li-S batteries by employing attapulgite nanorods assisted separator surface engineering.展开更多
This study was aimed at investigating the performance of anaerobic rotating biological cont- reactor treating synthetic wastewater containing a mixture of heavy metals under sulfate redu condition. Statistically valid...This study was aimed at investigating the performance of anaerobic rotating biological cont- reactor treating synthetic wastewater containing a mixture of heavy metals under sulfate redu condition. Statistically valid factorial design of experiments was carried out to understand dynamics of metal removal using this bioreactor system. Copper removal was maximum （〉98% followed by other heavy metals at their respective low inlet concentrations. Metal loading rates than 3.7 mg/L· h in case of Cu（II）; less than 1.69 mg/L· h for Ni（II）, Pb（II）, Zn（II）, Fe（III） and C are favorable to the performance of the An-RBC reactor. Removal efficiency of the heavy metals 1 mixture depended on the metal species and their inlet loading concentrations. Analysis of n precipitates formed in the sulfidogenic bioreactor by field emission scanning electron microscopyalong with energy dispersive X-ray spectroscopy （FESEM-EDX） confirmed metal sulfide precipitationby SRB. All these results clearly revealed that the attached growth biofilm bioreactor is well suited for heavy metal removal from complex mixture.展开更多
Two new isostructural multi-metal beryllium borates, m^3 Li Na4Be4B10O24F（M = Sr（1）, Cd（2））, have been synthesized by spontaneous crystallization. The structures were verified by single-crystal X-ray crystallogr...Two new isostructural multi-metal beryllium borates, m^3 Li Na4Be4B10O24F（M = Sr（1）, Cd（2））, have been synthesized by spontaneous crystallization. The structures were verified by single-crystal X-ray crystallography. The compounds crystallize in the trigonal space group R 3, with a = b = 9.4645（1） A, c = 38.842（8） A, V = 3013.2（6） A3, Z = 6, F（000） = 2568, Dc = 3.005 g/cm^3, Mr = 908.9, R = 0.0327, w R = 0.0678, μ = 8.160 mm-1 for Sr3 Li Na4Be4B10O24F and a = b = 9.3019（8） A, c = 37.782（7） A, V = 2831.12（9） A3, Z = 6, F（000） = 2748, Dc = 3.459 g/cm^3, Mr = 983.24, R = 0.0158, w R = 0.0455, μ = 3.586 mm-1 for Cd3 Li Na4Be4B10O24F. The structures are characterized by an infinite two-dimensional [Be8B16O40F2]∞ double layer bridged by [B12O24] groups like a sandwich structure, while the cations reside in tunnels along different directions. UV-vis-IR diffuse reflectance spectroscopy demonstrates that their cut-off edges are below 200 nm. Thermal analysis shows that they melt incongruently and their melting points are around 740-770 ℃.展开更多
The precise control on the combination of multiple metal atoms in the structure of metal-organic frameworks(MOFs)endowed by reticular chemistry,allows the obtaining of materials with compositions that are programmed f...The precise control on the combination of multiple metal atoms in the structure of metal-organic frameworks(MOFs)endowed by reticular chemistry,allows the obtaining of materials with compositions that are programmed for achieving enhanced reactivity.The present work illustrates how through the transformation of MOFs with desired arrangements of metal cations,multi-metal spinel oxides with precise compositions can be obtained,and used as catalyst precursor for the reverse water-gas shift reaction.The differences in the spinel initial composition and structure,determined by neutron powder diffraction,influence the overall catalytic activity with changes in the process of in s itu formation of active,metal-oxide supported metal nanoparticles,which have been monitored and characterized with in situ X-ray diffraction and photoelectron spectroscopy studies.展开更多
Laser additive manufacturing(LAM)is promising for fabricating multi-metallic component,but the mechanism of microstructural evolution at the interface of two metals is still needed to research further.In this study,a ...Laser additive manufacturing(LAM)is promising for fabricating multi-metallic component,but the mechanism of microstructural evolution at the interface of two metals is still needed to research further.In this study,a 316L stainless steel/Ti6Al4V alloy multi-metal was fabricated by LAM,and the mechanism of intermetallic phase transformation was deeply investigated.Results show that a strong reaction zone(SRZ)can be induced at the interface of the multi-metal.The phase constituents at the SRZ vary fromχ(Ti_(5)Fe_(17)Cr_(5))+Fe_(2)Ti+α′-Ti+β-Ti or FeTi to Fe_(2)Ti+χwhen the laser power is increased.When the scanning speed is further decreased,the thickness of the SRZ is significantly increased,andα′-Ti phase is also formed at this region besides Fe_(2)Ti andχphases.Moreover,the micro-hardness at the SRZ is increased,caused by the intermetallic phase transformation and elemental interdiffusion at the interface.展开更多
Bioinspired Multi-Metal Structures(MMSs)combine distinct properties of multiple materials,benefiting from improved properties and providing superior designs.Additive Manufacturing(AM)exhibits enormous advantages in ap...Bioinspired Multi-Metal Structures(MMSs)combine distinct properties of multiple materials,benefiting from improved properties and providing superior designs.Additive Manufacturing(AM)exhibits enormous advantages in applying different materials and geometries according to the desired functions at specific locations of the structure,having great potential in fabricating multi-materials structures.However,current AM techniques have difficulty manufacturing 3D MMSs without material cross-contamination flexibly and reliably.This study demonstrates a reliable,fast,and flexible direct ink writing method to fabricate 3D MMSs.The in-situ material-switching system enables the deposition of multiple metallic materials across different layers and within the same layer.3D Fe-Cu MMSs with complex geometries and fine details are fabricated as proof of concept.The microstructures,chemical and phase compositions,and tensile fracture surfaces of the Fe-Cu interfaces indicate a well-bonded interface without cracks,delamination,or material cross-contamination.We envision this novel method making other metallic combinations and even metal-ceramic components.It paves the way for manufacturing 3D MMSs using AM and establishes the possibilities of numerous MMSs applications in engineering fields.展开更多
Morphology of zinc alloy layer,from zincate solution with zinc sulfate and zinc oxide respectively,together with the consequent deposit was observed with SEM and back scattering electron image.EDS was applied to analy...Morphology of zinc alloy layer,from zincate solution with zinc sulfate and zinc oxide respectively,together with the consequent deposit was observed with SEM and back scattering electron image.EDS was applied to analyze the components of zinc alloy layer and the interface of high-Si aluminum alloy substrate-zinc alloy-deposit.Besides,the surface morphology of the zincated aluminum alloy after immersing in 3.5% NaCl solution for 7 d,is observed and the corrosion rate was calculate.Finally,tension test is conducted to quantify the adhesion between high-Si aluminum cast substrate and the deposit.The results show that,the zinc oxide contained zincating solution with sodium potassium tartrate and sodium citrate is a better one in multi-metal zincating solutions.The zinc alloy layer from this one gets stable performance,perfect adhesion with deposit,and good corrosion resistance.展开更多
In order to find out a multi-metal zincate solution to get good micromorphology and fine adhesion of coatings, sulfate zincate and zinc oxide zincate with different chelating agents combinations, of which there are 8 ...In order to find out a multi-metal zincate solution to get good micromorphology and fine adhesion of coatings, sulfate zincate and zinc oxide zincate with different chelating agents combinations, of which there are 8 solutions are designed. CHI630 electrochemical test system is applied to measure the φ—t curves of zincate process and Tafle curves of zincated plates in 3.5% NaCl medium. The analyzed results show that when molar ratio of sodium hydroxide to zinc ions is constant, the better chelating agents combination for multi-metal zincation solution is the combination of sodium potassium tartrate and sodium citrate in zinc oxide solution, from which zinc alloy is high in potential and perfect in corrosion resistance. After the second zincate immersion for 60s, the immersion potential is -1.606V(vs SCE). The corrosion current density is 6.612, J_ corr/(A·cm -2); and the corrosion potential is -1.381, φ_ corr(I=0)/V.展开更多
基金financially supported by the National Science Foundation of China (Grant No.21802126).
文摘Water electrolysis is a promising technology to produce hydrogen but it was severely restricted by the slow oxygen evolution reaction(OER).Herein,we firstly reported an advanced electrocatalyst of MOF-derived hollow Zn-Co-Ni sulfides(ZnS@Co_(9)S_(8)@Ni_(3)S_(2)-1/2,abbreviated as ZCNS-1/2)nanosword arrays(NSAs)with remarkable hydrogen evolution reaction(HER),OER and corresponding water electrolysis performance.To reach a current density of 10 mA cm^(-2),the cell voltage of assembled ZCNS-1/2//ZCNS-1/2 for urea electrolysis(1.314 V)is 208 mV lower than that for water electrolysis(1.522 V)and stably catalyzed for over 15 h,substantially outperforming the most reported water and urea electrolysis electrocatalysts.Density functional theory calculations and experimental result clearly reveal that the properties of large electrochemical active surface area(ECSA)caused by hollow NSAs and fast charge transfer resulted from the Co_(9)S_(8)@Ni_(3)S_(2) heterostructure endow the ZCNS-1/2 electrode with an enhanced electrocatalytic performance.
基金supported by the National Natural Science Foundation of China(Nos.51861165101,51822706,51777200)Beijing Natural Science Foundation(No.JQ19012)DNL Cooperation Fund,CAS(DNL201912)。
文摘Lithium-sulfur(Li-S)batteries have been recognized as one of the most promising candidates for nextgeneration portable electronic devices,owing to their extremely high energy density and low cost.However,the dissolution of lithium polysulfides(LiPSs)and consequent"shuttle effect"seriously hinder the practical deployment of Li-S batteries.Herein,multi-metal oxide nanorods named attapulgite are proposed as multifunctional ionic sieve to immobilize LiPSs and further promote the regulation of LiPSs.Attapulgite,consisting of Al,Mg,Fe,Si and O ions,possesses more polar sites to immobilize LiPSs in comparison with single metal oxides.In addition,the catalytic nature(Fe ions)of attapulgite avails the LiPSs conversion reaction,which is further confirmed by the linear sweep voltammetry and electrochemical impedance spectroscopy.Benefited from the synergistic effect of multi-metal oxide and conductive carbon,the Li-S battery with the modified separator delivers remarkable discharge capacities of 1059.4 mAh g-1 and 792.5 mAh g-1 for the first and 200th cycle at 0.5 C,respectively.The work presents an effective way to improve the electrochemical performance of Li-S batteries by employing attapulgite nanorods assisted separator surface engineering.
文摘This study was aimed at investigating the performance of anaerobic rotating biological cont- reactor treating synthetic wastewater containing a mixture of heavy metals under sulfate redu condition. Statistically valid factorial design of experiments was carried out to understand dynamics of metal removal using this bioreactor system. Copper removal was maximum （〉98% followed by other heavy metals at their respective low inlet concentrations. Metal loading rates than 3.7 mg/L· h in case of Cu（II）; less than 1.69 mg/L· h for Ni（II）, Pb（II）, Zn（II）, Fe（III） and C are favorable to the performance of the An-RBC reactor. Removal efficiency of the heavy metals 1 mixture depended on the metal species and their inlet loading concentrations. Analysis of n precipitates formed in the sulfidogenic bioreactor by field emission scanning electron microscopyalong with energy dispersive X-ray spectroscopy （FESEM-EDX） confirmed metal sulfide precipitationby SRB. All these results clearly revealed that the attached growth biofilm bioreactor is well suited for heavy metal removal from complex mixture.
基金supported by the National Natural Science Foundation of China(No.50972149,61138004,51402316)the National Instrumentation Program(No.2012YQ120048)
文摘Two new isostructural multi-metal beryllium borates, m^3 Li Na4Be4B10O24F（M = Sr（1）, Cd（2））, have been synthesized by spontaneous crystallization. The structures were verified by single-crystal X-ray crystallography. The compounds crystallize in the trigonal space group R 3, with a = b = 9.4645（1） A, c = 38.842（8） A, V = 3013.2（6） A3, Z = 6, F（000） = 2568, Dc = 3.005 g/cm^3, Mr = 908.9, R = 0.0327, w R = 0.0678, μ = 8.160 mm-1 for Sr3 Li Na4Be4B10O24F and a = b = 9.3019（8） A, c = 37.782（7） A, V = 2831.12（9） A3, Z = 6, F（000） = 2748, Dc = 3.459 g/cm^3, Mr = 983.24, R = 0.0158, w R = 0.0455, μ = 3.586 mm-1 for Cd3 Li Na4Be4B10O24F. The structures are characterized by an infinite two-dimensional [Be8B16O40F2]∞ double layer bridged by [B12O24] groups like a sandwich structure, while the cations reside in tunnels along different directions. UV-vis-IR diffuse reflectance spectroscopy demonstrates that their cut-off edges are below 200 nm. Thermal analysis shows that they melt incongruently and their melting points are around 740-770 ℃.
基金We acknowledge Institut Laue-Langevin and Spanish initiatives on Neutron Scattering(ILL-SpINS)for beamtime at instrum ent D2B and G.Cuellofor assistance during data acquisition(10.5291/ILL-DATA.5-21-1114).We thank M.C.Capel for the TEM images and TEM-EDS analysis acquisition at Instituto de Catalisis y Petroleoquimica(CSIC).Funding:Work at Instituto de Ciencia de Materiales de Madrid-Consejo Superior de Instigaciones Cientfficas(CSIC)has been supported by the Spanish Research Agency(Agenda Estatal de Investigacion,AEI),Projects MAT2016-78465-R,CTQ2017-87262-R.This work was supported by the EU(ERC CoG HyMAP 648319)and Spanish MINECO(ENE2016-79608-C2-1-R).Authors also wish to thank to“Com unidad de Madrid”and European Structural Funds for their financial support to FotoArt-CM project(S2018/NMT-4367).F.G.acknowledges financial support from MINECO Ramon y Cajal program(RyC-2015-18384).
文摘The precise control on the combination of multiple metal atoms in the structure of metal-organic frameworks(MOFs)endowed by reticular chemistry,allows the obtaining of materials with compositions that are programmed for achieving enhanced reactivity.The present work illustrates how through the transformation of MOFs with desired arrangements of metal cations,multi-metal spinel oxides with precise compositions can be obtained,and used as catalyst precursor for the reverse water-gas shift reaction.The differences in the spinel initial composition and structure,determined by neutron powder diffraction,influence the overall catalytic activity with changes in the process of in s itu formation of active,metal-oxide supported metal nanoparticles,which have been monitored and characterized with in situ X-ray diffraction and photoelectron spectroscopy studies.
基金supported by the Key Research and Develop Program of Anhui Province(No.202004b11020030)the China Postdoctoral Science Foundation(No.2020M680292)。
文摘Laser additive manufacturing(LAM)is promising for fabricating multi-metallic component,but the mechanism of microstructural evolution at the interface of two metals is still needed to research further.In this study,a 316L stainless steel/Ti6Al4V alloy multi-metal was fabricated by LAM,and the mechanism of intermetallic phase transformation was deeply investigated.Results show that a strong reaction zone(SRZ)can be induced at the interface of the multi-metal.The phase constituents at the SRZ vary fromχ(Ti_(5)Fe_(17)Cr_(5))+Fe_(2)Ti+α′-Ti+β-Ti or FeTi to Fe_(2)Ti+χwhen the laser power is increased.When the scanning speed is further decreased,the thickness of the SRZ is significantly increased,andα′-Ti phase is also formed at this region besides Fe_(2)Ti andχphases.Moreover,the micro-hardness at the SRZ is increased,caused by the intermetallic phase transformation and elemental interdiffusion at the interface.
基金National Natural Science Foundation of China,China(Grant ID:52105343 and 52021003)China Postdoctoral Science Foundation,China(Grant ID:2021M701387 and 2022T150259)Department of Science and Technology of Jilin Province,China(Grant ID:2020122214JC).
文摘Bioinspired Multi-Metal Structures(MMSs)combine distinct properties of multiple materials,benefiting from improved properties and providing superior designs.Additive Manufacturing(AM)exhibits enormous advantages in applying different materials and geometries according to the desired functions at specific locations of the structure,having great potential in fabricating multi-materials structures.However,current AM techniques have difficulty manufacturing 3D MMSs without material cross-contamination flexibly and reliably.This study demonstrates a reliable,fast,and flexible direct ink writing method to fabricate 3D MMSs.The in-situ material-switching system enables the deposition of multiple metallic materials across different layers and within the same layer.3D Fe-Cu MMSs with complex geometries and fine details are fabricated as proof of concept.The microstructures,chemical and phase compositions,and tensile fracture surfaces of the Fe-Cu interfaces indicate a well-bonded interface without cracks,delamination,or material cross-contamination.We envision this novel method making other metallic combinations and even metal-ceramic components.It paves the way for manufacturing 3D MMSs using AM and establishes the possibilities of numerous MMSs applications in engineering fields.
基金This work is financially supported by the Foundation of Basic Research of Harbin Engineering Universi-ty( HEUFT06030)
文摘Morphology of zinc alloy layer,from zincate solution with zinc sulfate and zinc oxide respectively,together with the consequent deposit was observed with SEM and back scattering electron image.EDS was applied to analyze the components of zinc alloy layer and the interface of high-Si aluminum alloy substrate-zinc alloy-deposit.Besides,the surface morphology of the zincated aluminum alloy after immersing in 3.5% NaCl solution for 7 d,is observed and the corrosion rate was calculate.Finally,tension test is conducted to quantify the adhesion between high-Si aluminum cast substrate and the deposit.The results show that,the zinc oxide contained zincating solution with sodium potassium tartrate and sodium citrate is a better one in multi-metal zincating solutions.The zinc alloy layer from this one gets stable performance,perfect adhesion with deposit,and good corrosion resistance.
文摘In order to find out a multi-metal zincate solution to get good micromorphology and fine adhesion of coatings, sulfate zincate and zinc oxide zincate with different chelating agents combinations, of which there are 8 solutions are designed. CHI630 electrochemical test system is applied to measure the φ—t curves of zincate process and Tafle curves of zincated plates in 3.5% NaCl medium. The analyzed results show that when molar ratio of sodium hydroxide to zinc ions is constant, the better chelating agents combination for multi-metal zincation solution is the combination of sodium potassium tartrate and sodium citrate in zinc oxide solution, from which zinc alloy is high in potential and perfect in corrosion resistance. After the second zincate immersion for 60s, the immersion potential is -1.606V(vs SCE). The corrosion current density is 6.612, J_ corr/(A·cm -2); and the corrosion potential is -1.381, φ_ corr(I=0)/V.
