High-purity copper(Cu) with excellent thermal and electrical conductivity, is crucial in modern technological applications, including heat exchangers, integrated circuits, and superconducting magnets. The current puri...High-purity copper(Cu) with excellent thermal and electrical conductivity, is crucial in modern technological applications, including heat exchangers, integrated circuits, and superconducting magnets. The current purification process is mainly based on the zone/electrolytic refining or anion exchange, however, which excessively relies on specific integrated equipment with ultra-high vacuum or chemical solution environment, and is also bothered by external contaminants and energy consumption. Here we report a simple approach to purify the Cu foils from 99.9%(3N) to 99.99%(4N) by a temperature-gradient thermal annealing technique, accompanied by the kinetic evolution of single crystallization of Cu.The success of purification mainly relies on(i) the segregation of elements with low effective distribution coefficient driven by grain-boundary movements and(ii) the high-temperature evaporation of elements with high saturated vapor pressure.The purified Cu foils display higher flexibility(elongation of 70%) and electrical conductivity(104% IACS) than that of the original commercial rolled Cu foils(elongation of 10%, electrical conductivity of ~ 100% IACS). Our results provide an effective strategy to optimize the as-produced metal medium, and therefore will facilitate the potential applications of Cu foils in precision electronic products and high-frequency printed circuit boards.展开更多
Since the first isolation of graphene by Geim and Novoselov in 2004,this two-dimensional(2D)material has attracted significant attention from the scientific and engineering communities.^(1)Due to its structure with a ...Since the first isolation of graphene by Geim and Novoselov in 2004,this two-dimensional(2D)material has attracted significant attention from the scientific and engineering communities.^(1)Due to its structure with a single layer of covalently bonded sp^(2)-hybridized carbon atoms,graphene has superior mechanical,electrical,optical,and thermal properties.^(2-4)Although mechanical exfoliation remains an ideal method for obtaining highquality graphene,its scalability is severely limited;thus,it is impractical for industrial applications.In pursuit of a method suitable for large-scale production,research has been performed using chemical vapor deposition(CVD)methods for synthesizing graphene on metal substrates.展开更多
基金Project supported by the Basic and Applied Basic Research Foundation of Guangdong Province,China(Grant Nos.2019A1515110302 and 2022A1515140003)the Key Research and Development Program of Guangdong Province,China(Grant Nos.2020B010189001,2021B0301030002,2019B010931001,and 2018B030327001)+5 种基金the National Natural Science Foundation of China(Grant Nos.52172035,52025023,52322205,51991342,52021006,51991344,52100115,11888101,92163206,12104018,and 12274456)the National Key Research and Development Program of China(Grant Nos.2021YFB3200303,2022YFA1405600,2018YFA0703700,2021YFA1400201,and 2021YFA1400502)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB33000000)the Pearl River Talent Recruitment Program of Guangdong Province,China(Grant No.2019ZT08C321)China Postdoctoral Science Foundation(Grant Nos.2020T130022 and 2020M680178)the Science and Technology Plan Project of Liaoning Province,China(Grant No.2021JH2/10100012).
文摘High-purity copper(Cu) with excellent thermal and electrical conductivity, is crucial in modern technological applications, including heat exchangers, integrated circuits, and superconducting magnets. The current purification process is mainly based on the zone/electrolytic refining or anion exchange, however, which excessively relies on specific integrated equipment with ultra-high vacuum or chemical solution environment, and is also bothered by external contaminants and energy consumption. Here we report a simple approach to purify the Cu foils from 99.9%(3N) to 99.99%(4N) by a temperature-gradient thermal annealing technique, accompanied by the kinetic evolution of single crystallization of Cu.The success of purification mainly relies on(i) the segregation of elements with low effective distribution coefficient driven by grain-boundary movements and(ii) the high-temperature evaporation of elements with high saturated vapor pressure.The purified Cu foils display higher flexibility(elongation of 70%) and electrical conductivity(104% IACS) than that of the original commercial rolled Cu foils(elongation of 10%, electrical conductivity of ~ 100% IACS). Our results provide an effective strategy to optimize the as-produced metal medium, and therefore will facilitate the potential applications of Cu foils in precision electronic products and high-frequency printed circuit boards.
基金supported by the National Natural Science Foundation of China(52172035,52025023 and 92163206)Guangdong Major Project of Basic and Applied Basic Research(2021B0301030002)+4 种基金the National Key R&D Program of China(2021YFA1400502)the National Postdoctoral Program for Innovative Talents(BX20230022)Beijing Municipal Science and Technology Project(Z221100005822003)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB33000000)the New Cornerstone Science Foundation through the XPLORER PRIZE.
文摘Since the first isolation of graphene by Geim and Novoselov in 2004,this two-dimensional(2D)material has attracted significant attention from the scientific and engineering communities.^(1)Due to its structure with a single layer of covalently bonded sp^(2)-hybridized carbon atoms,graphene has superior mechanical,electrical,optical,and thermal properties.^(2-4)Although mechanical exfoliation remains an ideal method for obtaining highquality graphene,its scalability is severely limited;thus,it is impractical for industrial applications.In pursuit of a method suitable for large-scale production,research has been performed using chemical vapor deposition(CVD)methods for synthesizing graphene on metal substrates.
