Surface-enhanced Raman spectroscopy(SERS)has advanced significantly since its inception.Numerous experimental and theoretical efforts have been made to understand the SERS effect and demonstrate its potential.Due to i...Surface-enhanced Raman spectroscopy(SERS)has advanced significantly since its inception.Numerous experimental and theoretical efforts have been made to understand the SERS effect and demonstrate its potential.Due to its extremely high sensitivity and selectivity and ability to provide molecular fingerprint information,SERS has a wide range of applications in surface and interfacial chemistry,energy,materials,biomedicine,environmental analysis,etc.This review aims to provide readers with an understanding of the principles,methodologies,and applications of SERS.We briefly introduce the fundamental theory of the SERS enhancement mechanism and summarize the details of the preparation of SERS-active substrates.Recent applications of SERS in energy systems are then highlighted,including probing surface reactions and interfacial charge transfer of batteries and electrocatalysts.Finally,the challenges and prospects of SERS research are discussed.展开更多
Benefiting from a principally contaminant-free and well-defined surface,single-crystal electrodes offer new insights into interfacial processes and are important in electrochemistry.The early impetus for using single-...Benefiting from a principally contaminant-free and well-defined surface,single-crystal electrodes offer new insights into interfacial processes and are important in electrochemistry.The early impetus for using single-crystal electrodes in electrocatalysis was to investigate the surface structure at the atomic level for the reactions that are sensitive to the surface.These studies were usually performed in an ultra-high vacuum with atomic force microscopy(AFM),scanning tunneling microscope(STM),and X-ray methods to avoid the contamination.However,such characterizations are limited in their ability to identify chemical species definitively,a limitation that has similarly plagued the study of single-crystals.Recent advances in shellisolated nanoparticle-enhanced Raman spectroscopy(SHINERS)have enabled the detection of reaction intermediates on singlecrystal electrodes,in which shell-isolated nanoparticles on the single-crystal electrode can enhance the Raman signal from the surface,without changing the surface structure and electrochemical response.Thus,this work aims to review recent advances in Raman spectroelectrochemical studies on single-crystal electrode surfaces.The discussion focuses on how SHINERS technology has enabled the effective detection of intermediate species and,when combined with the electrochemical method,has yielded novel insights into the dynamic evolution of surface structure and electrocatalytic reaction mechanisms.Finally,the challenges and future of single-crystal electrodes are introduced.展开更多
Conventional intermetallics are strong but brit-tle.However,multi-principal element intermetallics,also termed as high-entropy intermetallics(HEIs)in the recent high-entropy alloy literature,are strong but malleable,s...Conventional intermetallics are strong but brit-tle.However,multi-principal element intermetallics,also termed as high-entropy intermetallics(HEIs)in the recent high-entropy alloy literature,are strong but malleable,some of which even show appreciable ductility and fracture toughness at room temperature.In this article,we provide a focused review on the recent researches on HEIs,from the fundamentals,such as the concept of HEIs,the formation rules to the structural and functional properties of HEIs.The results hitherto reported clearly show that the HEIs with distinct properties could be a promising material for future structural and functional applications.展开更多
Ir-Ni-Ta metallic glasses(MGs)exhibit an array of superior high-temperature properties,making them attractive for applications at high temperatures or in harsh environments.However,Ir-Ni-Ta bulk MGs are quite brittle ...Ir-Ni-Ta metallic glasses(MGs)exhibit an array of superior high-temperature properties,making them attractive for applications at high temperatures or in harsh environments.However,Ir-Ni-Ta bulk MGs are quite brittle and often fracture catastrophically even before plastic yielding,significantly undercutting their high-strength advantage.Here,we show that the Ir-Ni-Ta MGs are not intrinsically brittle,but rather malleable when the feature size is reduced to micro/nano-scales.All tested Ir-Ni-Ta MG micropillars with a diameter ranging from~500 nm to~5μm display a large plastic strain above 25%(the maximum up to 35%),together with a yield strength up to 7 GPa,well exceeding the strength recorded in most metallic materials.The intrinsic shear stability of Ir-Ni-Ta MGs,as characterized by the normalized shear displacement during a shear event,is much larger than those malleable Zr-and Cu-based MGs.Our results suggest that Ir-Ni-Ta MGs are excellent candidates for micro/nanoscale structural applications used at high-temperature or extreme conditions.展开更多
基金supported by the National Key Research and Development Program of China (2020YFB1505800)the National Natural Science Foundation of China (22005130,21925404,22174165,21902137,and 21991151)+1 种基金the China Postdoctoral Science Foundation (Bx20220187)the Natural Science Foundation of Fujian Province of China (2021J01988).
文摘Surface-enhanced Raman spectroscopy(SERS)has advanced significantly since its inception.Numerous experimental and theoretical efforts have been made to understand the SERS effect and demonstrate its potential.Due to its extremely high sensitivity and selectivity and ability to provide molecular fingerprint information,SERS has a wide range of applications in surface and interfacial chemistry,energy,materials,biomedicine,environmental analysis,etc.This review aims to provide readers with an understanding of the principles,methodologies,and applications of SERS.We briefly introduce the fundamental theory of the SERS enhancement mechanism and summarize the details of the preparation of SERS-active substrates.Recent applications of SERS in energy systems are then highlighted,including probing surface reactions and interfacial charge transfer of batteries and electrocatalysts.Finally,the challenges and prospects of SERS research are discussed.
基金supported by the National Key Research and Development Program of China (2020YFB1505800)the National Natural Science Foundation of China (21925404,22005130,and 21991151)the China Postdoctoral Science Foundation (BX20220187)。
文摘Benefiting from a principally contaminant-free and well-defined surface,single-crystal electrodes offer new insights into interfacial processes and are important in electrochemistry.The early impetus for using single-crystal electrodes in electrocatalysis was to investigate the surface structure at the atomic level for the reactions that are sensitive to the surface.These studies were usually performed in an ultra-high vacuum with atomic force microscopy(AFM),scanning tunneling microscope(STM),and X-ray methods to avoid the contamination.However,such characterizations are limited in their ability to identify chemical species definitively,a limitation that has similarly plagued the study of single-crystals.Recent advances in shellisolated nanoparticle-enhanced Raman spectroscopy(SHINERS)have enabled the detection of reaction intermediates on singlecrystal electrodes,in which shell-isolated nanoparticles on the single-crystal electrode can enhance the Raman signal from the surface,without changing the surface structure and electrochemical response.Thus,this work aims to review recent advances in Raman spectroelectrochemical studies on single-crystal electrode surfaces.The discussion focuses on how SHINERS technology has enabled the effective detection of intermediate species and,when combined with the electrochemical method,has yielded novel insights into the dynamic evolution of surface structure and electrocatalytic reaction mechanisms.Finally,the challenges and future of single-crystal electrodes are introduced.
基金financially supported by the General Research Fund (GRF) from Research Grant Council,the Hong Kong Government (Nos.CityU11213118 and CityU11200719)the fund from City University of Hong Kong (No.7005438)
文摘Conventional intermetallics are strong but brit-tle.However,multi-principal element intermetallics,also termed as high-entropy intermetallics(HEIs)in the recent high-entropy alloy literature,are strong but malleable,some of which even show appreciable ductility and fracture toughness at room temperature.In this article,we provide a focused review on the recent researches on HEIs,from the fundamentals,such as the concept of HEIs,the formation rules to the structural and functional properties of HEIs.The results hitherto reported clearly show that the HEIs with distinct properties could be a promising material for future structural and functional applications.
基金supported by the National Key Research and Development Plan(2018YFA0703603)Guangdong Major Project of Basic and Applied Basic Research,China(2019B030302010)+1 种基金the National Natural Science Foundation of China(51822107,11790291 and 61888102)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB30000000)。
文摘Ir-Ni-Ta metallic glasses(MGs)exhibit an array of superior high-temperature properties,making them attractive for applications at high temperatures or in harsh environments.However,Ir-Ni-Ta bulk MGs are quite brittle and often fracture catastrophically even before plastic yielding,significantly undercutting their high-strength advantage.Here,we show that the Ir-Ni-Ta MGs are not intrinsically brittle,but rather malleable when the feature size is reduced to micro/nano-scales.All tested Ir-Ni-Ta MG micropillars with a diameter ranging from~500 nm to~5μm display a large plastic strain above 25%(the maximum up to 35%),together with a yield strength up to 7 GPa,well exceeding the strength recorded in most metallic materials.The intrinsic shear stability of Ir-Ni-Ta MGs,as characterized by the normalized shear displacement during a shear event,is much larger than those malleable Zr-and Cu-based MGs.Our results suggest that Ir-Ni-Ta MGs are excellent candidates for micro/nanoscale structural applications used at high-temperature or extreme conditions.