Chirality,the property that an object cannot coincide with its mirror image arising from lack of mirror symmetry,is ubiquitous in nature at various length scales.The physical and chemical properties are strongly relat...Chirality,the property that an object cannot coincide with its mirror image arising from lack of mirror symmetry,is ubiquitous in nature at various length scales.The physical and chemical properties are strongly related to the nature of chiral complexes,playing a significant role in various fields such as photonics,biochemistry,medicine and catalysis.In particular,the recent flexible design of chiral metal nanostructures offers one platform for deeply understanding the origin of chirality and one roadmap for the precise construction of chiral nanomaterials directed by the applications.Herein,we summarize the different geometries and classical synthetic approaches to chiral noble metal nanomaterials.Moreover,chiroptical properties and potential applications of chiral metal nanostructures are discussed as well.Finally,the opportunities and challenges toward the synthesis and application of chiral metal nanostructures are proposed.展开更多
Based on the lightning monitoring and FY4A satellite data in 12 periods during a thunderstorm,the relationship between lightning activity and four satellite digital products:blackbody radiation brightness temperature(...Based on the lightning monitoring and FY4A satellite data in 12 periods during a thunderstorm,the relationship between lightning activity and four satellite digital products:blackbody radiation brightness temperature(TBB),cloud top temperature(CTT),cloud top height(CTH)and cloud top pressure(CTP)was quantitatively analyzed.The following conclusions were obtained:(1)at lightning location,90.5%of TBB values were less than 214.1 K;88.5%of CTT values were less than 207.7 K;88.5%of CTP values were less than 137.7 hPa,and 88.5%of CTH values were greater than 14872 m.At location without lightning,92.5%of TBB values were greater than 214.1 K;90.4%of CTT values were greater than 207.7 K;89%of CTP values were greater than 137.7 hPa,and 92%of CTH values were less than 14872 m.(2)Lightning activity was concentrated in the cloud area with TBB between 190-210 K,CTT between 185-210 K,CTP between 50-150 hPa and CTH between 12-18 km.Lightning intensity was roughly positively correlated with TBB,CTT and CTP,and negatively correlated with CTH.With the increase of CTH,lightning intensity decreased.(3)TBB,CTT,CTP and CTH can well indicate the location and activity frequency of lightning in thunderstorm weather.展开更多
The active site engineering of electrocatalysts,as one of the most economical and technological approaches,is a promising strategy to enhance the intrinsic activity and selectivity towards electrochemical CO_(2)reduct...The active site engineering of electrocatalysts,as one of the most economical and technological approaches,is a promising strategy to enhance the intrinsic activity and selectivity towards electrochemical CO_(2)reduction reaction.Herein,an indium-based porphyrin framework(In-TCPP)with a well-defined structure,highly dispersed catalytic center,and good stability was constructed for efficient CO_(2)-to-formate conversion.In-TCPP could achieve a high Faraday efficiency for formate(90%)and a cathodic energy efficiency of 63.8%in flow cells.In situ attenuated total reflectance Fourier transform infrared spectroscopy and density functional theory calculation confirm that the crucial intermediate is*COOH species which contributes to the formation of formate.This work is expected to provide novel insights into the precise design of active sites for high-performance electrocatalysts towards electrochemical CO_(2)reduction reaction.展开更多
Rationally modulating the adsorption configuration of the key*CO intermediate could facilitate carbon±carbon(C±C)coupling to generate multi-carbon products in the electrochemical CO_(2) reduction reaction.In...Rationally modulating the adsorption configuration of the key*CO intermediate could facilitate carbon±carbon(C±C)coupling to generate multi-carbon products in the electrochemical CO_(2) reduction reaction.In this work,theoretical calculations reveal that C±C coupling via atopadsorbed*CHO and hollow-adsorbed*CO over Cu sites is an energetically favorable pathway.As a proof of concept,a tandem trimetallic AuAgCu heterojunction(Au@Ag/Cu)was prepared,where the atop-adsorbed*CO over Au@Ag sites could migrate to Cu sites with hollow adsorption configuration,and then the asymmetric C±C coupling via transferred hollow-adsorbed*CO and existed atop-adsorbed*CHO over Cu sites facilitates the formation of the ethanol product,exhibiting a maximum Faraday efficiency of 65.9%at a low potential of−0.3 V vs.reverse hydrogen electrode.Our work provides new insights into the intrinsic understanding of tandem catalysis by regulating adsorption configuration of the intermediate products.展开更多
Covalent organic frameworks(COFs)represent an emerging class of crystalline porous polymers with high porosity,good stability,and adjustable structure,and their excellent characteristics lay a solid foundation for ele...Covalent organic frameworks(COFs)represent an emerging class of crystalline porous polymers with high porosity,good stability,and adjustable structure,and their excellent characteristics lay a solid foundation for electrocatalysis.This review systematically introduces the design principles of the catalytic sites in two-dimensional(2D)COF-based electrocatalysts and analyzes the relationship between 2D COF structure and their electrocatalytic performances.In particular,the recent progress in the field of 2D COFs as electrocatalysts is comprehensively summarized.Finally,we discuss the current shortcomings and challenges on tailoring 2D COF for high-performance electrocatalysts in details,and look forward to promoting more researches on 2D COF-based electrocatalysts.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.22071172,21902148,12205165,50835002 and 51105102)。
文摘Chirality,the property that an object cannot coincide with its mirror image arising from lack of mirror symmetry,is ubiquitous in nature at various length scales.The physical and chemical properties are strongly related to the nature of chiral complexes,playing a significant role in various fields such as photonics,biochemistry,medicine and catalysis.In particular,the recent flexible design of chiral metal nanostructures offers one platform for deeply understanding the origin of chirality and one roadmap for the precise construction of chiral nanomaterials directed by the applications.Herein,we summarize the different geometries and classical synthetic approaches to chiral noble metal nanomaterials.Moreover,chiroptical properties and potential applications of chiral metal nanostructures are discussed as well.Finally,the opportunities and challenges toward the synthesis and application of chiral metal nanostructures are proposed.
基金Supported by Guizhou Provincial Science and Technology Fund Project(QIANKEHEJICHU-ZK[2022]GENERAL245)。
文摘Based on the lightning monitoring and FY4A satellite data in 12 periods during a thunderstorm,the relationship between lightning activity and four satellite digital products:blackbody radiation brightness temperature(TBB),cloud top temperature(CTT),cloud top height(CTH)and cloud top pressure(CTP)was quantitatively analyzed.The following conclusions were obtained:(1)at lightning location,90.5%of TBB values were less than 214.1 K;88.5%of CTT values were less than 207.7 K;88.5%of CTP values were less than 137.7 hPa,and 88.5%of CTH values were greater than 14872 m.At location without lightning,92.5%of TBB values were greater than 214.1 K;90.4%of CTT values were greater than 207.7 K;89%of CTP values were greater than 137.7 hPa,and 92%of CTH values were less than 14872 m.(2)Lightning activity was concentrated in the cloud area with TBB between 190-210 K,CTT between 185-210 K,CTP between 50-150 hPa and CTH between 12-18 km.Lightning intensity was roughly positively correlated with TBB,CTT and CTP,and negatively correlated with CTH.With the increase of CTH,lightning intensity decreased.(3)TBB,CTT,CTP and CTH can well indicate the location and activity frequency of lightning in thunderstorm weather.
基金This work was supported by the National Natural Science Foundation of China(Nos.22071172,52121002,51733004,51725304,and 21907043)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB12030300)the Ministry of Science and Technology of China(No.2018YFA0703200)。
文摘The active site engineering of electrocatalysts,as one of the most economical and technological approaches,is a promising strategy to enhance the intrinsic activity and selectivity towards electrochemical CO_(2)reduction reaction.Herein,an indium-based porphyrin framework(In-TCPP)with a well-defined structure,highly dispersed catalytic center,and good stability was constructed for efficient CO_(2)-to-formate conversion.In-TCPP could achieve a high Faraday efficiency for formate(90%)and a cathodic energy efficiency of 63.8%in flow cells.In situ attenuated total reflectance Fourier transform infrared spectroscopy and density functional theory calculation confirm that the crucial intermediate is*COOH species which contributes to the formation of formate.This work is expected to provide novel insights into the precise design of active sites for high-performance electrocatalysts towards electrochemical CO_(2)reduction reaction.
基金National Natural Science Foundation of China (22071172 and 22375142)2022 Subsidized Project of Tianjin University Graduate Arts and Science Excellence Innovation Award Program (B2-2022-002)+3 种基金Innovation Funding Project of Science and Technology,China National Petroleum Corporation(2022DQ02-0408)financial support from the National Natural Science Foundation of China (52373233)SIAT International Joint Lab Project (E3G113)Shenzhen Science and Technology Program (KQTD20221101093647058)。
文摘Rationally modulating the adsorption configuration of the key*CO intermediate could facilitate carbon±carbon(C±C)coupling to generate multi-carbon products in the electrochemical CO_(2) reduction reaction.In this work,theoretical calculations reveal that C±C coupling via atopadsorbed*CHO and hollow-adsorbed*CO over Cu sites is an energetically favorable pathway.As a proof of concept,a tandem trimetallic AuAgCu heterojunction(Au@Ag/Cu)was prepared,where the atop-adsorbed*CO over Au@Ag sites could migrate to Cu sites with hollow adsorption configuration,and then the asymmetric C±C coupling via transferred hollow-adsorbed*CO and existed atop-adsorbed*CHO over Cu sites facilitates the formation of the ethanol product,exhibiting a maximum Faraday efficiency of 65.9%at a low potential of−0.3 V vs.reverse hydrogen electrode.Our work provides new insights into the intrinsic understanding of tandem catalysis by regulating adsorption configuration of the intermediate products.
基金This project was supported by the National Natural Science Foundation of China(Nos.22071172,21872103,and 52073208).
文摘Covalent organic frameworks(COFs)represent an emerging class of crystalline porous polymers with high porosity,good stability,and adjustable structure,and their excellent characteristics lay a solid foundation for electrocatalysis.This review systematically introduces the design principles of the catalytic sites in two-dimensional(2D)COF-based electrocatalysts and analyzes the relationship between 2D COF structure and their electrocatalytic performances.In particular,the recent progress in the field of 2D COFs as electrocatalysts is comprehensively summarized.Finally,we discuss the current shortcomings and challenges on tailoring 2D COF for high-performance electrocatalysts in details,and look forward to promoting more researches on 2D COF-based electrocatalysts.
