In-space manufacturing is an emerging and promising research field in space industry,which benefits the development of space explorations.Owing to the microgravity,high vacuum and complexity of the space environment,a...In-space manufacturing is an emerging and promising research field in space industry,which benefits the development of space explorations.Owing to the microgravity,high vacuum and complexity of the space environment,a special manufacturing strategy for alloys is highly demanded for the in-space manufacturing.Herein,a lowtemperature thermoplastic metallic welding method was proposed and employed for La-based metallic glass ribbons.With the sandwiched structures of La-and Zr-based ribbons,the welded samples exhibit a competitive fracture strength and an increased tensile strain than those of the welded la-based samples due to the second phase strengthening.This suggests that metallic glass is an ideal material candidate for in-space manufacturing,and can be well manufactured at a nonmelting state with good mechanical performances.In addition,the thermoplastic manufacturing method can also feature a moderate processing time window.In general,this work presents the promising potential of low-temperature thermoplastic welding strategy for in-space manufacturing of metallic materials.展开更多
Inspired by the great success of ultrathin two-dimensional(2D)layered crystals,more and more attention is being paid to preparing 2D nanostructures from non-layered materials.They can significantly enrich the 2D mater...Inspired by the great success of ultrathin two-dimensional(2D)layered crystals,more and more attention is being paid to preparing 2D nanostructures from non-layered materials.They can significantly enrich the 2D materials and 2D heterostructures family,extend their application prospects,and bring us distinct properties from their bulk counterparts due to the strong 2D confinement effect.However,the realization of 2D non-layered semiconductors with strong light-harvesting capability and the ability to construct high-performance 2D heterostructures is still a critical challenge.Herein,we successfully synthesized 2D PbSe semiconductors with a large lateral dimension and ultrathin thickness via van der Waals epitaxy.The fabricated 2D PbSe device exhibits good electrical conductivity and superior multi-wavelength photoresponse performance with high responsivity(∼10^(3) A/W)and impressive detectivity(∼2×10^(11) Jones).Furthermore,we demonstrate that 2D PbSe nanosheets can serve as component units for constructing high-performance heterostructure devices.With our strategy,ultrahigh current on/off ratio(∼10^(8))and rectification ratio(∼10^()6),as well as high responsivity(∼3×10^(3) A/W)and detectivity(∼7×10^(12) Jones),can be achieved in PbSe/MoS_(2) back-gated transistors.These results indicate that 2D PbSe nanosheets and their heterostructures have tremendous applications potential in electrical and optoelectronic devices.展开更多
基金the National Natural Science Foundation of China(51901244)Qian Xuesen Laboratory of Space Technology。
文摘In-space manufacturing is an emerging and promising research field in space industry,which benefits the development of space explorations.Owing to the microgravity,high vacuum and complexity of the space environment,a special manufacturing strategy for alloys is highly demanded for the in-space manufacturing.Herein,a lowtemperature thermoplastic metallic welding method was proposed and employed for La-based metallic glass ribbons.With the sandwiched structures of La-and Zr-based ribbons,the welded samples exhibit a competitive fracture strength and an increased tensile strain than those of the welded la-based samples due to the second phase strengthening.This suggests that metallic glass is an ideal material candidate for in-space manufacturing,and can be well manufactured at a nonmelting state with good mechanical performances.In addition,the thermoplastic manufacturing method can also feature a moderate processing time window.In general,this work presents the promising potential of low-temperature thermoplastic welding strategy for in-space manufacturing of metallic materials.
基金supported by the National Key R&D Program of China(2018YFA0703700)the National Natural Science Foundation of China(91964203,62104171,62104172,and 62004142)+2 种基金the Natural Science Foundation of Hubei Province(2021CFB037)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB44000000)the Fundamental Research Funds for the Central Universities(2042021kf0067)。
文摘Inspired by the great success of ultrathin two-dimensional(2D)layered crystals,more and more attention is being paid to preparing 2D nanostructures from non-layered materials.They can significantly enrich the 2D materials and 2D heterostructures family,extend their application prospects,and bring us distinct properties from their bulk counterparts due to the strong 2D confinement effect.However,the realization of 2D non-layered semiconductors with strong light-harvesting capability and the ability to construct high-performance 2D heterostructures is still a critical challenge.Herein,we successfully synthesized 2D PbSe semiconductors with a large lateral dimension and ultrathin thickness via van der Waals epitaxy.The fabricated 2D PbSe device exhibits good electrical conductivity and superior multi-wavelength photoresponse performance with high responsivity(∼10^(3) A/W)and impressive detectivity(∼2×10^(11) Jones).Furthermore,we demonstrate that 2D PbSe nanosheets can serve as component units for constructing high-performance heterostructure devices.With our strategy,ultrahigh current on/off ratio(∼10^(8))and rectification ratio(∼10^()6),as well as high responsivity(∼3×10^(3) A/W)and detectivity(∼7×10^(12) Jones),can be achieved in PbSe/MoS_(2) back-gated transistors.These results indicate that 2D PbSe nanosheets and their heterostructures have tremendous applications potential in electrical and optoelectronic devices.