Lithium metal batteries(LMBs)are considered the most promising energy stor-age devices for applications such as electrical vehicles owing to its tremendous theoretical capacity(3860 mAh g−1).However,the serious safety...Lithium metal batteries(LMBs)are considered the most promising energy stor-age devices for applications such as electrical vehicles owing to its tremendous theoretical capacity(3860 mAh g−1).However,the serious safety issues and poor cycling performance caused by the dendritic crystal growth during deposi-tion are concerned for any rechargeable batteries with a lithium metal anode.To make widespread adoption a possibility,considerable efforts have been devoted to suppressing lithium(Li)dendrite growth.In this review,the recent strategies to developing dendrite free Li anode,including constructing an artifi-cial solid electrolyte interface,current collector modification,separator film improvement,and electrolyte additive,are summarized.The merits and short-comings for different strategies are reviewed and a general summary and per-spective on the next generation rechargeable batteries are presented.展开更多
To synthesize graphene economically and efficiently,as well as to improve the interface bonding between graphene and metal and to recede the aggregation issue of graphene,in this work,an easy and scalable bottom-up st...To synthesize graphene economically and efficiently,as well as to improve the interface bonding between graphene and metal and to recede the aggregation issue of graphene,in this work,an easy and scalable bottom-up strategy for the mass production of metal nanoparticles modified graphene nanoplates(GNPs)was proposed.Cu nanoparticles modified GNPs(Cu-GNPs)and Ni nanoparticles modified GNPs(Ni-GNPs)were fabricated through this method,and then compounded with Al via ball milling technique.The asobtained Ni-GNPs/Al composite showed simultaneously improved strength and toughness compared with unreinforced Al,while the Cu-GNPs/Al composite presented a greater strengthening effect.The microstructure and interface of the two composites were carefully characterized and investigated to reveal the difference.First principle study was also adopted to explore the binding energy of different interface structures.This study could provide new insights into the fabrication of GNPs and the control of interface in GNPs/Al composites.展开更多
CO oxidation is probably the most studied reaction in heterogeneous catalysis.This reaction has become a hot topic with the discovery of nanogold catalysts,which are active at low temperatures（at or below room temper...CO oxidation is probably the most studied reaction in heterogeneous catalysis.This reaction has become a hot topic with the discovery of nanogold catalysts,which are active at low temperatures（at or below room temperature）.Au catalysts are the benchmark for judging the activities of other metals in CO oxidation.Pt-group metals（PGMs） that give comparable performances are of particular interest.In this mini-review,we summarize the advances in various PGM（Pt,Pd,Ir,Rh,Ru）catalysts that have high catalytic activities in low-temperature CO oxidation arising from reducible supports or the presence of OH species.The effects of the size of the metal species and the importance of the interface between the metal and the reducible support are covered and discussed in terms of their promotional role in CO oxidation at low temperatures.展开更多
Laminated metal composites(LMCs) are a unique composite material and have great application prospects in automobiles, ships, aircraft,and other manufacturing industries. As lightweight materials, the Mg/Al LMCs are ex...Laminated metal composites(LMCs) are a unique composite material and have great application prospects in automobiles, ships, aircraft,and other manufacturing industries. As lightweight materials, the Mg/Al LMCs are expected to combine the advantages of both Mg and Al alloys to broaden their application prospects. Roll-bonding is the most popular process for the fabrication of Mg/Al LMCs due to high production efficiency and good product quality stability. The roll-bonding process involves the deformation of the substrates and the formation of the interfacial diffusion layer. The latter will directly determine the interface bonding strength of Mg/Al LMCs. Bonding strength is very sensitive to the thickness of the reaction layer in the diffusion layer. When the thickness of the reaction layer exceeds 5 μm, the bonding strength decreases sharply. Therefore, controlling the thickness of the reaction layer is very important for the design of rolling parameters.The latest research also showed that the addition of intermediate layer metal and the construction of three-dimensional interfaces can further improve the interface bonding strength. How to apply these methods to roll-bonding is the focus of future research. Recently, a new rolling technique, corrugated roll/plat roll rolling+flat roll/flat roll rolling has been developed to fabricate Mg/Al LMCs. It can effectively promote the deformation of the hard layer and generate a wavy interface, resulting in the enhancement of the bonding quality and rolling quality.In the current review, the effects of rolling parameters and subsequent annealing on the interface structure of Mg/Al LMCs were elaborated in detail. The application of some special rolling techniques in the preparation of Mg/Al LMCs was also summarized. The latest research results on the relationship between interface structure and mechanical properties of Mg/Al LMCs were reviewed. Finally, further research directions in this field were proposed.展开更多
Firm joins were obtained between Ti（C,N）-based cermet and steel with Ag-Cu-Zn-Ni filler metal by vacuum brazing. The effects of technological parameters such as brazing temperature, holding time, and filler thicknes...Firm joins were obtained between Ti（C,N）-based cermet and steel with Ag-Cu-Zn-Ni filler metal by vacuum brazing. The effects of technological parameters such as brazing temperature, holding time, and filler thickness on the shear strength of the joints were investigated. The microstructure of welded area and the reaction products of the filler metal were examined by scanning electron microscopy （SEM）, metallographic microscope （OM）, energy-dispersive X-ray analysis （EDS）, and X-ray diffraction （XRD）. The brazing temperature of 870℃, holding time of 15 min, and filler thickness of 0.4 mm are a set of optimum technological parameters, under which the maximum shear strength of the joints, 176.5 MPa, is achieved. The results of microstructure show that the wettability of the filler metal on Ti（C,N）-based cermet and steel is well. A mutual solution layer and a diffusion layer exist between the welding base materials and the filler metal.展开更多
10%(volume fraction) SiCp/Al-Mg composites with different Mg contents were successfully fabricated by semi-solid mechanical stirring technique under optimum processing conditions.Effects of Mg content on microstructur...10%(volume fraction) SiCp/Al-Mg composites with different Mg contents were successfully fabricated by semi-solid mechanical stirring technique under optimum processing conditions.Effects of Mg content on microstructure and mechanical properties were studied by scanning electron microscopy(SEM),X-ray diffractometry(XRD) and transmission electron microscopy(TEM).The results indicate that SiC particles disperse homogeneously in Al-Mg matrix and interfacial reaction between Al matrix and SiC particles is effectively controlled.Distribution of SiCp reinforcement and interfacial bonding are improved by adding Mg.Additionally,the mechanical properties of composites are remarkably improved with the Mg content increasing.展开更多
To date,much efforts have been devoted to the high-efficiency noble metal-free electrocatalysts for hydrogen-and oxygen-involving energy conversion reactions,due to their abundance,low cost and nultifunctionally.Surfa...To date,much efforts have been devoted to the high-efficiency noble metal-free electrocatalysts for hydrogen-and oxygen-involving energy conversion reactions,due to their abundance,low cost and nultifunctionally.Surface/interface engineering is found to be effective in achieving novel physicochemical properties and synergistic effects in nanomaterials for electrocatalysis.Among various engineering strategies,heteroatom-doping has been regarded as a most promising method to improve the electrocatalytic performance via the regulation of electronic structure of catalysts,and numerous works were reported on the synthesis method and mechanism investigation of heteroatom-doping electrocatalysts,though the heteroatom-doping can only provide limited active sites.Engineering of other defects such as vacancies and edge sites and construction of heterostructure have shown to open up a potential avenue for the development of noble metal-free electrocatalysts.In addition,surface functionalization can attach various molecules onto the surface of materials to easily modify their physical or chemical properties,being as a promising complement or substitute for offering materials with catalytic properties.This paper gives the insights into the diverse strategies of surface/interface engineering of the highefficiency noble metal-free electrocatalysts for energy-related electrochemical reactions.The significant advances are summarized.The unique advantages and mechanisms for specific applications are highlighted.The current challenges and outlook of this growing field are also discussed.展开更多
An orthogonal experiment scheme was designed to investigate the effects of the Cu content,compaction pressure,and sintering temperature on the microstructures and mechanical and thermal properties of(30−50)wt.%Cu/Inva...An orthogonal experiment scheme was designed to investigate the effects of the Cu content,compaction pressure,and sintering temperature on the microstructures and mechanical and thermal properties of(30−50)wt.%Cu/Invar bi-metal matrix composites fabricated via spark plasma sintering(SPS).The results indicated that as the Cu content increased from 30 to 50 wt.%,a continuous Cu network gradually appeared,and the density,thermal conductivity(TC)and coefficient of thermal expansion of the composites noticeably increased,but the tensile strength decreased.The increase in the sintering temperature promoted the Cu/Invar interface diffusion,leading to a reduction in the TC but an enhancement in the tensile strength of the composites.The compaction pressure comprehensively affected the thermal properties of the composites.The 50wt.%Cu/Invar composite sintered at 700℃ and 60 MPa had the highest TC(90.7 W/(m·K)),which was significantly higher than the TCs obtained for most of the previously reported Cu/Invar composites.展开更多
基金National Science Foundation,Grant/Award Numbers:1700785,1724941,1917577China Postdoctoral Science Foundation,Grant/Award Number:2020M671606+1 种基金National Natural Science Foundation of China,Grant/Award Numbers:21805221,21905221Natural Science Foundation of Jiangsu Province,Grant/Award Number:BK20191190。
文摘Lithium metal batteries(LMBs)are considered the most promising energy stor-age devices for applications such as electrical vehicles owing to its tremendous theoretical capacity(3860 mAh g−1).However,the serious safety issues and poor cycling performance caused by the dendritic crystal growth during deposi-tion are concerned for any rechargeable batteries with a lithium metal anode.To make widespread adoption a possibility,considerable efforts have been devoted to suppressing lithium(Li)dendrite growth.In this review,the recent strategies to developing dendrite free Li anode,including constructing an artifi-cial solid electrolyte interface,current collector modification,separator film improvement,and electrolyte additive,are summarized.The merits and short-comings for different strategies are reviewed and a general summary and per-spective on the next generation rechargeable batteries are presented.
基金Key Foundational Technology Development of Yunnan Academic Institutes(2002KFZX-31)Candidates of the Young and Middle Aged Academic Leaders of Yunnan Province (2006py01-42)
基金the National Natural Science Foundation of China(Grant Nos.51771130,51531004,and 51422104)the Tianjin youth talent support program+1 种基金the Tianjin Natural Science Funds for Distinguished Young(Grant No.17JCJQJC44300)the Tianjin Science and Technology Support Project(Grant No.17ZXCLGX00060)。
文摘To synthesize graphene economically and efficiently,as well as to improve the interface bonding between graphene and metal and to recede the aggregation issue of graphene,in this work,an easy and scalable bottom-up strategy for the mass production of metal nanoparticles modified graphene nanoplates(GNPs)was proposed.Cu nanoparticles modified GNPs(Cu-GNPs)and Ni nanoparticles modified GNPs(Ni-GNPs)were fabricated through this method,and then compounded with Al via ball milling technique.The asobtained Ni-GNPs/Al composite showed simultaneously improved strength and toughness compared with unreinforced Al,while the Cu-GNPs/Al composite presented a greater strengthening effect.The microstructure and interface of the two composites were carefully characterized and investigated to reveal the difference.First principle study was also adopted to explore the binding energy of different interface structures.This study could provide new insights into the fabrication of GNPs and the control of interface in GNPs/Al composites.
基金supported by the National Natural Science Foundation of China(21076211,21203181,21576251,21676269)the "Strategic Priority Research Program" of the Chinese Academy of Sciences(XDB17020100)+1 种基金the National Key projects for Fundamental Research and Development of China(2016YFA0202801)Department of Science and Technology of Liaoning Province under contract of 2015020086-101~~
文摘CO oxidation is probably the most studied reaction in heterogeneous catalysis.This reaction has become a hot topic with the discovery of nanogold catalysts,which are active at low temperatures（at or below room temperature）.Au catalysts are the benchmark for judging the activities of other metals in CO oxidation.Pt-group metals（PGMs） that give comparable performances are of particular interest.In this mini-review,we summarize the advances in various PGM（Pt,Pd,Ir,Rh,Ru）catalysts that have high catalytic activities in low-temperature CO oxidation arising from reducible supports or the presence of OH species.The effects of the size of the metal species and the importance of the interface between the metal and the reducible support are covered and discussed in terms of their promotional role in CO oxidation at low temperatures.
基金supported by Guangdong Major Project of Basic and Applied Basic Research,No. 2020B0301030006。
文摘Laminated metal composites(LMCs) are a unique composite material and have great application prospects in automobiles, ships, aircraft,and other manufacturing industries. As lightweight materials, the Mg/Al LMCs are expected to combine the advantages of both Mg and Al alloys to broaden their application prospects. Roll-bonding is the most popular process for the fabrication of Mg/Al LMCs due to high production efficiency and good product quality stability. The roll-bonding process involves the deformation of the substrates and the formation of the interfacial diffusion layer. The latter will directly determine the interface bonding strength of Mg/Al LMCs. Bonding strength is very sensitive to the thickness of the reaction layer in the diffusion layer. When the thickness of the reaction layer exceeds 5 μm, the bonding strength decreases sharply. Therefore, controlling the thickness of the reaction layer is very important for the design of rolling parameters.The latest research also showed that the addition of intermediate layer metal and the construction of three-dimensional interfaces can further improve the interface bonding strength. How to apply these methods to roll-bonding is the focus of future research. Recently, a new rolling technique, corrugated roll/plat roll rolling+flat roll/flat roll rolling has been developed to fabricate Mg/Al LMCs. It can effectively promote the deformation of the hard layer and generate a wavy interface, resulting in the enhancement of the bonding quality and rolling quality.In the current review, the effects of rolling parameters and subsequent annealing on the interface structure of Mg/Al LMCs were elaborated in detail. The application of some special rolling techniques in the preparation of Mg/Al LMCs was also summarized. The latest research results on the relationship between interface structure and mechanical properties of Mg/Al LMCs were reviewed. Finally, further research directions in this field were proposed.
基金supported by the National Natural Science Foundation of China (No. 50074014)
文摘Firm joins were obtained between Ti（C,N）-based cermet and steel with Ag-Cu-Zn-Ni filler metal by vacuum brazing. The effects of technological parameters such as brazing temperature, holding time, and filler thickness on the shear strength of the joints were investigated. The microstructure of welded area and the reaction products of the filler metal were examined by scanning electron microscopy （SEM）, metallographic microscope （OM）, energy-dispersive X-ray analysis （EDS）, and X-ray diffraction （XRD）. The brazing temperature of 870℃, holding time of 15 min, and filler thickness of 0.4 mm are a set of optimum technological parameters, under which the maximum shear strength of the joints, 176.5 MPa, is achieved. The results of microstructure show that the wettability of the filler metal on Ti（C,N）-based cermet and steel is well. A mutual solution layer and a diffusion layer exist between the welding base materials and the filler metal.
基金Project(2006CB605203-3) supported by the National Basic Research Program of China
文摘10%(volume fraction) SiCp/Al-Mg composites with different Mg contents were successfully fabricated by semi-solid mechanical stirring technique under optimum processing conditions.Effects of Mg content on microstructure and mechanical properties were studied by scanning electron microscopy(SEM),X-ray diffractometry(XRD) and transmission electron microscopy(TEM).The results indicate that SiC particles disperse homogeneously in Al-Mg matrix and interfacial reaction between Al matrix and SiC particles is effectively controlled.Distribution of SiCp reinforcement and interfacial bonding are improved by adding Mg.Additionally,the mechanical properties of composites are remarkably improved with the Mg content increasing.
基金supported by the Natural Science Foundation of Shandong Province(ZR2019PB013)the Natural Science Foundation of Tianjin(19JCZDJC37700)the National Natural Science Foundation of China(21421001 and 21875118)。
文摘To date,much efforts have been devoted to the high-efficiency noble metal-free electrocatalysts for hydrogen-and oxygen-involving energy conversion reactions,due to their abundance,low cost and nultifunctionally.Surface/interface engineering is found to be effective in achieving novel physicochemical properties and synergistic effects in nanomaterials for electrocatalysis.Among various engineering strategies,heteroatom-doping has been regarded as a most promising method to improve the electrocatalytic performance via the regulation of electronic structure of catalysts,and numerous works were reported on the synthesis method and mechanism investigation of heteroatom-doping electrocatalysts,though the heteroatom-doping can only provide limited active sites.Engineering of other defects such as vacancies and edge sites and construction of heterostructure have shown to open up a potential avenue for the development of noble metal-free electrocatalysts.In addition,surface functionalization can attach various molecules onto the surface of materials to easily modify their physical or chemical properties,being as a promising complement or substitute for offering materials with catalytic properties.This paper gives the insights into the diverse strategies of surface/interface engineering of the highefficiency noble metal-free electrocatalysts for energy-related electrochemical reactions.The significant advances are summarized.The unique advantages and mechanisms for specific applications are highlighted.The current challenges and outlook of this growing field are also discussed.
基金the International Science&Technology Cooperation Program of China(No.2014DFA50860).
文摘An orthogonal experiment scheme was designed to investigate the effects of the Cu content,compaction pressure,and sintering temperature on the microstructures and mechanical and thermal properties of(30−50)wt.%Cu/Invar bi-metal matrix composites fabricated via spark plasma sintering(SPS).The results indicated that as the Cu content increased from 30 to 50 wt.%,a continuous Cu network gradually appeared,and the density,thermal conductivity(TC)and coefficient of thermal expansion of the composites noticeably increased,but the tensile strength decreased.The increase in the sintering temperature promoted the Cu/Invar interface diffusion,leading to a reduction in the TC but an enhancement in the tensile strength of the composites.The compaction pressure comprehensively affected the thermal properties of the composites.The 50wt.%Cu/Invar composite sintered at 700℃ and 60 MPa had the highest TC(90.7 W/(m·K)),which was significantly higher than the TCs obtained for most of the previously reported Cu/Invar composites.
