Cong-Qiao Xu, Tiantong Wang, Chong Wang, Xin-Ran Dong, Huijun Zheng, Ya Zhao, Li-Li Pan, Jiayue Yang, Weiqing Zhang, Guorong Wu, Hua Xie, Gang Li, Jun Li, Ling Jiang, Xueming Yang, Lai-Sheng Wang
Despite major progress in the investigation of boron cluster anions, direct experimental study of neutral boron clusters remains a significant challenge because of the difficulty in size selection. Here we report a size-specific study of the neutral B9 cluster using threshold photoionization with a tunable vacuum ultraviolet free electron laser. The ionization potential of B9 is measured to be 8.45 ± 0.02 eV and it is found to have a heptagonal bipyramid D7h structure, quite different from the planar molecular wheel of the B9- anionic cluster. Chemical bonding analyses reveal superior stability of the bipyramidal structure arising from delocalized s and p bonding interactions within the B7 ring and between the B7 ring and the capping atoms. Photoionization of B9 breaks the single-electron B-B bond of the capping atoms, which undergo off-axis distortion to enhance interactions with the B7 ring in the singlet ground state of B9+. The single-electron B-B bond of the capping atoms appears to be crucial in stabilizing the D7h structure of B9. This work opens avenues for direct size-dependent experimental studies of a large variety of neutral boron clusters to explore the stepwise development of network structures.
{"title":"Observation of the Smallest Three-Dimensional Neutral Boron Cluster","authors":"Cong-Qiao Xu, Tiantong Wang, Chong Wang, Xin-Ran Dong, Huijun Zheng, Ya Zhao, Li-Li Pan, Jiayue Yang, Weiqing Zhang, Guorong Wu, Hua Xie, Gang Li, Jun Li, Ling Jiang, Xueming Yang, Lai-Sheng Wang","doi":"10.1002/anie.202419089","DOIUrl":"https://doi.org/10.1002/anie.202419089","url":null,"abstract":"Despite major progress in the investigation of boron cluster anions, direct experimental study of neutral boron clusters remains a significant challenge because of the difficulty in size selection. Here we report a size-specific study of the neutral B9 cluster using threshold photoionization with a tunable vacuum ultraviolet free electron laser. The ionization potential of B9 is measured to be 8.45 ± 0.02 eV and it is found to have a heptagonal bipyramid D7h structure, quite different from the planar molecular wheel of the B9- anionic cluster. Chemical bonding analyses reveal superior stability of the bipyramidal structure arising from delocalized s and p bonding interactions within the B7 ring and between the B7 ring and the capping atoms. Photoionization of B9 breaks the single-electron B-B bond of the capping atoms, which undergo off-axis distortion to enhance interactions with the B7 ring in the singlet ground state of B9+. The single-electron B-B bond of the capping atoms appears to be crucial in stabilizing the D7h structure of B9. This work opens avenues for direct size-dependent experimental studies of a large variety of neutral boron clusters to explore the stepwise development of network structures.","PeriodicalId":125,"journal":{"name":"Angewandte Chemie International Edition","volume":"90 1","pages":""},"PeriodicalIF":16.6,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jianbin Liu, Yao Liu, Bing Nan, Dashuai Wang, Christopher Allen, Zhichao Gong, Guanchao He, Kaixing Fu, Gonglan Ye, Huilong Fei
Site density and turnover frequency are the two fundamental kinetic descriptors that determine the oxygen reduction activity of iron-nitrogen-carbon (Fe−N−C) catalysts. However, it remains a grand challenge to simultaneously optimize these two parameters in a single Fe−N−C catalyst. Here we show that treating a typical Fe−N−C catalyst with ammonium iodine (NH4I) vapor via a one-step chemical vapor deposition process not only increases the surface area and porosity of the catalyst (and thus enhanced exposure of active sites) via the etching effect of the in-situ released NH3, but also regulates the electronic structure of the Fe−N4 moieties by the iodine dopants incorporated into the carbon matrix. As a result, the NH4I-treated Fe−N−C catalyst possesses both high values in the site density of 2.15×1019 sites g−1 (×2 enhancement compared to the untreated counterpart) and turnover frequency of 3.71 electrons site−1 s−1 (×3 enhancement) that correspond to a high mass activity of 12.78 A g−1, as determined by in-situ nitrite stripping technique. Moreover, this catalyst exhibits an excellent oxygen reduction activity in base with a half-wave potential (E1/2) of 0.924 V and acceptable activity in acid with E1/2 = 0.795 V, and superior power density of 249.1 mW cm−2 in zinc-air batteries.
{"title":"A Two-in-One Strategy to Simultaneously Boost the Site Density and Turnover Frequency of Fe−N−C Oxygen Reduction Catalysts","authors":"Jianbin Liu, Yao Liu, Bing Nan, Dashuai Wang, Christopher Allen, Zhichao Gong, Guanchao He, Kaixing Fu, Gonglan Ye, Huilong Fei","doi":"10.1002/anie.202425196","DOIUrl":"https://doi.org/10.1002/anie.202425196","url":null,"abstract":"Site density and turnover frequency are the two fundamental kinetic descriptors that determine the oxygen reduction activity of iron-nitrogen-carbon (Fe−N−C) catalysts. However, it remains a grand challenge to simultaneously optimize these two parameters in a single Fe−N−C catalyst. Here we show that treating a typical Fe−N−C catalyst with ammonium iodine (NH4I) vapor via a one-step chemical vapor deposition process not only increases the surface area and porosity of the catalyst (and thus enhanced exposure of active sites) via the etching effect of the in-situ released NH3, but also regulates the electronic structure of the Fe−N4 moieties by the iodine dopants incorporated into the carbon matrix. As a result, the NH4I-treated Fe−N−C catalyst possesses both high values in the site density of 2.15×1019 sites g−1 (×2 enhancement compared to the untreated counterpart) and turnover frequency of 3.71 electrons site−1 s−1 (×3 enhancement) that correspond to a high mass activity of 12.78 A g−1, as determined by in-situ nitrite stripping technique. Moreover, this catalyst exhibits an excellent oxygen reduction activity in base with a half-wave potential (E1/2) of 0.924 V and acceptable activity in acid with E1/2 = 0.795 V, and superior power density of 249.1 mW cm−2 in zinc-air batteries.","PeriodicalId":125,"journal":{"name":"Angewandte Chemie International Edition","volume":"4 1","pages":""},"PeriodicalIF":16.6,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Samantha L. Le, Christopher R. O’Connor, Taek-Seung Kim, Christian Reece
The dynamic response of heterogeneous catalytic materials to their environment opens a wide variety of possible surface states which may have increased catalytic activity. In this work, we find that it is possible to generate a surface state with increased catalytic activity over metallic 2nm Pt nanoparticles by performing a thermal treatment of the CO*-covered Pt catalyst. This state is characterised by its ability to oxidise CO to CO2 at room temperature. By combining pressure pulse experiments with in situ spectroscopy we correlate the formation of this high-activity state with the desorption of weakly bound CO* molecules from well-coordinated Pt sites. This high-activity state is metastable, degrading after elevated thermal treatments or upon readsorption of CO at room temperature. We conclude that this metastable state is highly localised to the surface of the nanoparticle, however its exact atomic structure remains open to speculation.
{"title":"A Metastable State Facilitates Low Temperature CO Oxidation over Pt Nanoparticles","authors":"Samantha L. Le, Christopher R. O’Connor, Taek-Seung Kim, Christian Reece","doi":"10.1002/anie.202423880","DOIUrl":"https://doi.org/10.1002/anie.202423880","url":null,"abstract":"The dynamic response of heterogeneous catalytic materials to their environment opens a wide variety of possible surface states which may have increased catalytic activity. In this work, we find that it is possible to generate a surface state with increased catalytic activity over metallic 2nm Pt nanoparticles by performing a thermal treatment of the CO*-covered Pt catalyst. This state is characterised by its ability to oxidise CO to CO2 at room temperature. By combining pressure pulse experiments with in situ spectroscopy we correlate the formation of this high-activity state with the desorption of weakly bound CO* molecules from well-coordinated Pt sites. This high-activity state is metastable, degrading after elevated thermal treatments or upon readsorption of CO at room temperature. We conclude that this metastable state is highly localised to the surface of the nanoparticle, however its exact atomic structure remains open to speculation.","PeriodicalId":125,"journal":{"name":"Angewandte Chemie International Edition","volume":"1 1","pages":""},"PeriodicalIF":16.6,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142974932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Reliable methods for rapidly constructing C(sp3)-rich three-dimensional polycycles are in high demand for organic synthesis and medicinal chemistry. Although there are various mature systems for synthesizing five- or six-membered polycycles, a catalytic platform for accessing diverse cycloheptanoid-containing polycyclic scaffolds is lacking. Herein, we describe a method for copper-catalyzed intramolecular 2-aminoallyl cation–diene (4 + 3) cycloaddition reactions. By using 1,3-diene-tethered ethynyl methylene cyclic carbamates as substrates, we were able to construct various cycloheptanoid-containing polycyclic scaffolds, which are present in many bioactive molecules. The cycloaddition products were rich in functionality that could undergo various chemical transformations. The synthetic utility of the method was illustrated by total synthesis of the natural products (±)-mint ketone and (±)-aphanamol I. Mechanistic studies indicated that the cycloadditions proceed via a concerted [4π + 2π] mechanism and that an endo-selective pathway is favored.
{"title":"Building Three-Dimensional Complexity by Intramolecular 2-Aminoallyl Cation–Diene (4 + 3) Cycloaddition","authors":"Lulu Shen, Tianzhu Qin, Chongling Jiao, Weiwei Zi","doi":"10.1002/anie.202423405","DOIUrl":"https://doi.org/10.1002/anie.202423405","url":null,"abstract":"Reliable methods for rapidly constructing C(sp3)-rich three-dimensional polycycles are in high demand for organic synthesis and medicinal chemistry. Although there are various mature systems for synthesizing five- or six-membered polycycles, a catalytic platform for accessing diverse cycloheptanoid-containing polycyclic scaffolds is lacking. Herein, we describe a method for copper-catalyzed intramolecular 2-aminoallyl cation–diene (4 + 3) cycloaddition reactions. By using 1,3-diene-tethered ethynyl methylene cyclic carbamates as substrates, we were able to construct various cycloheptanoid-containing polycyclic scaffolds, which are present in many bioactive molecules. The cycloaddition products were rich in functionality that could undergo various chemical transformations. The synthetic utility of the method was illustrated by total synthesis of the natural products (±)-mint ketone and (±)-aphanamol I. Mechanistic studies indicated that the cycloadditions proceed via a concerted [4π + 2π] mechanism and that an endo-selective pathway is favored.","PeriodicalId":125,"journal":{"name":"Angewandte Chemie International Edition","volume":"84 1","pages":""},"PeriodicalIF":16.6,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142974933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haiyan Li, Yuwei Zhang, Yubo Chen, Yang Li, Zhongjian Li, Bin Yang, Qinghua Zhang, Jianguo Lu, Lecheng Lei, Zhichuan J. Xu, Yang Hou
Electrochemical water splitting is a pivotal technology for storing intermittent electricity from renewable sources into hydrogen fuel. However, its overall energy efficiency is impeded by the sluggish oxygen evolution reaction (OER) at the anode. In the quest to design high-performance anode catalysts for driving the OER under non-acidic conditions, iron (Fe) has emerged as a crucial element. Although the profound impact of adventitious electrolyte Fen+ species on OER catalysis had been reported forty years ago, recent interest in tailoring the electrode-electrolyte interface has spurred studies on the controlled introduction of Fe ions into the electrolyte to improve OER performance. During the catalytic process, scenarios where the rate of Fen+ deposition on a specific host material outruns that of dissolution pave the way for establishing highly efficient and dynamically stable electrochemical interfaces for long-term steady operation. This review systematically summarizes recent endeavors devoted to elucidating the behaviors of in situ Fe(aq.) incorporation, the role of incorporated Fe sites in the OER, and critical factors influencing the interplay between the electrode surface and Fe ions in the electrolyte environment. Finally, unexplored issues related to comprehensively understanding and leveraging the dynamic exchange of Fen+ at the interface for improved OER catalysis are summarized.
{"title":"Leveraging Iron in the Electrolyte to Improve Oxygen Evolution Reaction Performance: Fundamentals, Strategies, and Perspectives","authors":"Haiyan Li, Yuwei Zhang, Yubo Chen, Yang Li, Zhongjian Li, Bin Yang, Qinghua Zhang, Jianguo Lu, Lecheng Lei, Zhichuan J. Xu, Yang Hou","doi":"10.1002/anie.202423071","DOIUrl":"https://doi.org/10.1002/anie.202423071","url":null,"abstract":"Electrochemical water splitting is a pivotal technology for storing intermittent electricity from renewable sources into hydrogen fuel. However, its overall energy efficiency is impeded by the sluggish oxygen evolution reaction (OER) at the anode. In the quest to design high-performance anode catalysts for driving the OER under non-acidic conditions, iron (Fe) has emerged as a crucial element. Although the profound impact of adventitious electrolyte Fen+ species on OER catalysis had been reported forty years ago, recent interest in tailoring the electrode-electrolyte interface has spurred studies on the controlled introduction of Fe ions into the electrolyte to improve OER performance. During the catalytic process, scenarios where the rate of Fen+ deposition on a specific host material outruns that of dissolution pave the way for establishing highly efficient and dynamically stable electrochemical interfaces for long-term steady operation. This review systematically summarizes recent endeavors devoted to elucidating the behaviors of in situ Fe(aq.) incorporation, the role of incorporated Fe sites in the OER, and critical factors influencing the interplay between the electrode surface and Fe ions in the electrolyte environment. Finally, unexplored issues related to comprehensively understanding and leveraging the dynamic exchange of Fen+ at the interface for improved OER catalysis are summarized.","PeriodicalId":125,"journal":{"name":"Angewandte Chemie International Edition","volume":"1 1","pages":""},"PeriodicalIF":16.6,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142974936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tingting Liu, Chen Chen, Zonghua Pu, Qiufeng Huang, Jiadong Jiang, Min Han, Wei Chen, Guangtao Yu, Yuzhi Sun, Shengyun Huang, Qingjun Chen, Abdullah M. Al-Enizi, Ayman Nafady, Xueqin Mu, Shichun Mu
Nanoscale metal borides, with exceptional physicochemical properties, have been attracted widespread attention. However, traditional synthesis methods of metal borides often lead to surface coking and large particle sizes. Herein, we have employed a flash Joule heating (FJH) technique to enable the ultrafast synthesis of metal boride nanomaterials. The synthesized materials encompass a wide range of diverse categories, including alkaline-earth metal borides (CaB6), transition metal borides (TiB2, VB2, CrB2, MoB, MoB2, MnB2, MnB4, FeB, CoB, NiB), noble-metal borides (RuB2, RuB1.1), and rare-earth metal borides (LaB6, CeB6). As an example, the RuB2 demonstrates highly desirable electrocatalytic performance for all-pH hydrogen evolution reaction (HER). Especially, under the acidic condition, it exhibits an overpotential as low as 15 mV at a current density of 10 mA cm-2, with a nearly 100% faradic efficiency. Additionally, in situ Raman spectra confirm that both Ru and B sites serve as active sites for the HER. Moreover, the stability of RuB2 can be further enhanced by optimizing the microenvironments of the anolyte composition (H+, K+). More importantly, the experimental and density functional theory (DFT) calculations reveal that the co-existence of H+ and K+ localized around the RuB2 plays a crucial role in further enhancing the stability.
{"title":"Ultrafast Synthesis of Nanoscale Metal Borides for Efficient Hydrogen Evolution","authors":"Tingting Liu, Chen Chen, Zonghua Pu, Qiufeng Huang, Jiadong Jiang, Min Han, Wei Chen, Guangtao Yu, Yuzhi Sun, Shengyun Huang, Qingjun Chen, Abdullah M. Al-Enizi, Ayman Nafady, Xueqin Mu, Shichun Mu","doi":"10.1002/anie.202425257","DOIUrl":"https://doi.org/10.1002/anie.202425257","url":null,"abstract":"Nanoscale metal borides, with exceptional physicochemical properties, have been attracted widespread attention. However, traditional synthesis methods of metal borides often lead to surface coking and large particle sizes. Herein, we have employed a flash Joule heating (FJH) technique to enable the ultrafast synthesis of metal boride nanomaterials. The synthesized materials encompass a wide range of diverse categories, including alkaline-earth metal borides (CaB6), transition metal borides (TiB2, VB2, CrB2, MoB, MoB2, MnB2, MnB4, FeB, CoB, NiB), noble-metal borides (RuB2, RuB1.1), and rare-earth metal borides (LaB6, CeB6). As an example, the RuB2 demonstrates highly desirable electrocatalytic performance for all-pH hydrogen evolution reaction (HER). Especially, under the acidic condition, it exhibits an overpotential as low as 15 mV at a current density of 10 mA cm-2, with a nearly 100% faradic efficiency. Additionally, in situ Raman spectra confirm that both Ru and B sites serve as active sites for the HER. Moreover, the stability of RuB2 can be further enhanced by optimizing the microenvironments of the anolyte composition (H+, K+). More importantly, the experimental and density functional theory (DFT) calculations reveal that the co-existence of H+ and K+ localized around the RuB2 plays a crucial role in further enhancing the stability.","PeriodicalId":125,"journal":{"name":"Angewandte Chemie International Edition","volume":"36 1","pages":""},"PeriodicalIF":16.6,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142981742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ruimin Lan, Zhuofeng Hu, Haoran Liu, Kui Shen, Hui Wang, Tingting Hou, Yingwei Li
An inevitable overoxidation process is considered as one of the most challenging problems in the direct conversion of methane (CH4) to methanol (CH3OH), which is limited by the uncontrollable cracking of key intermediates. Herein, we have successfully constructed a photocatalyst, the Fe-doped ZnO hollow polyhedron (Fe/ZnOHP), for the highly selective photoconversion of CH4 to CH3OH under mild conditions. In-situ experiments and density functional theory calculations confirmed that the introduction of Fe was able to decrease the energy level of the O 2p orbital, which passivated the activity of lattice oxygen in ZnO nanocrystals. This passivation effect greatly weakened the interaction between *CH3 and lattice oxygen, thus facilitating the conversion of *CH3O to *CH3 intermediate rather than the direct desorption of *CH3O. As a result, Fe/ZnOHP exhibited excellent CH3OH generation rate (ca. 1009 μmol gcat−1 h-1) and selectivity (ca. 96%) in the photocatalytic conversion of CH4 at room temperature and low pressure.
{"title":"Passivating Lattice Oxygen in ZnO Nanocrystals to Reduce its Interactions with the Key Intermediates for a Selective Photocatalytic Methane Oxidation to Methanol","authors":"Ruimin Lan, Zhuofeng Hu, Haoran Liu, Kui Shen, Hui Wang, Tingting Hou, Yingwei Li","doi":"10.1002/anie.202425186","DOIUrl":"https://doi.org/10.1002/anie.202425186","url":null,"abstract":"An inevitable overoxidation process is considered as one of the most challenging problems in the direct conversion of methane (CH4) to methanol (CH3OH), which is limited by the uncontrollable cracking of key intermediates. Herein, we have successfully constructed a photocatalyst, the Fe-doped ZnO hollow polyhedron (Fe/ZnOHP), for the highly selective photoconversion of CH4 to CH3OH under mild conditions. In-situ experiments and density functional theory calculations confirmed that the introduction of Fe was able to decrease the energy level of the O 2p orbital, which passivated the activity of lattice oxygen in ZnO nanocrystals. This passivation effect greatly weakened the interaction between *CH3 and lattice oxygen, thus facilitating the conversion of *CH3O to *CH3 intermediate rather than the direct desorption of *CH3O. As a result, Fe/ZnOHP exhibited excellent CH3OH generation rate (ca. 1009 μmol gcat−1 h-1) and selectivity (ca. 96%) in the photocatalytic conversion of CH4 at room temperature and low pressure.","PeriodicalId":125,"journal":{"name":"Angewandte Chemie International Edition","volume":"1 1","pages":""},"PeriodicalIF":16.6,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142981786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Honggen Wang, Yin Li, Xiao-Bin Liu, Vadym Sham, Ivan Logvinenko, Jiang-Hao Xue, Jun-Yunzi Wu, Jia-Luo Fu, Shuang Lin, Yuan Liu, Qingjiang Li, Pavel K. Mykhailiuk
A general method to convert simple exocyclic alkenes (no Ar-substituents) into saturated F2-rings has been developed. The reaction involves the IIII-reagent C6F5I(OAc)2 (F5-PIDA). The reaction efficiently works on the mg-, g-, and even multigram scale.
现已开发出一种将简单的外环烯（无 Ar 取代基）转化为饱和 F2 环的通用方法。该反应涉及 IIII 试剂 C6F5I(OAc)2 (F5-PIDA)。该反应在毫克、克甚至多克级上都能有效进行。
{"title":"Saturated F2-rings from Alkenes","authors":"Honggen Wang, Yin Li, Xiao-Bin Liu, Vadym Sham, Ivan Logvinenko, Jiang-Hao Xue, Jun-Yunzi Wu, Jia-Luo Fu, Shuang Lin, Yuan Liu, Qingjiang Li, Pavel K. Mykhailiuk","doi":"10.1002/anie.202422899","DOIUrl":"https://doi.org/10.1002/anie.202422899","url":null,"abstract":"A general method to convert simple exocyclic alkenes (no Ar-substituents) into saturated F2-rings has been developed. The reaction involves the IIII-reagent C6F5I(OAc)2 (F5-PIDA). The reaction efficiently works on the mg-, g-, and even multigram scale.","PeriodicalId":125,"journal":{"name":"Angewandte Chemie International Edition","volume":"8 1","pages":""},"PeriodicalIF":16.6,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142981778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ling Liu, Yuanxin Deng, Da-Hui Qu, Ben L. Feringa, He Tian, Qi Zhang
Kinetically controlled self-assembly is garnering increasing interest in the field of supramolecular polymers and materials, yet examples involving dynamic covalent exchange remain relatively unexplored. Here we report an unexpected dynamic covalent polymeric system whose aqueous self-assembly pathway is strongly influenced by the kinetics of evaporation of water. The key design is to integrate dual dynamic covalent bonds—including disulfide bonds and boroxine/borate—into a dynamic equilibrium system of monomers, polymers, and materials. This dual dynamic covalent design allows polymer growth and crosslinking to occur with the same spatiotemporal characteristics, governed solely by solvent evaporation. We found that a single building block can assemble into two distinct types of polymeric materials, each characterized by unique crosslinking topologies, orders, solubility, and macroscopic properties. The dual dynamic nature of the materials imparts them with intrinsic reconfigurability, such as interfacial repairability and close-loop chemical recyclability.
{"title":"Kinetic Control of Self-Assembly Pathway in Dual Dynamic Covalent Polymeric Systems","authors":"Ling Liu, Yuanxin Deng, Da-Hui Qu, Ben L. Feringa, He Tian, Qi Zhang","doi":"10.1002/anie.202424147","DOIUrl":"https://doi.org/10.1002/anie.202424147","url":null,"abstract":"Kinetically controlled self-assembly is garnering increasing interest in the field of supramolecular polymers and materials, yet examples involving dynamic covalent exchange remain relatively unexplored. Here we report an unexpected dynamic covalent polymeric system whose aqueous self-assembly pathway is strongly influenced by the kinetics of evaporation of water. The key design is to integrate dual dynamic covalent bonds—including disulfide bonds and boroxine/borate—into a dynamic equilibrium system of monomers, polymers, and materials. This dual dynamic covalent design allows polymer growth and crosslinking to occur with the same spatiotemporal characteristics, governed solely by solvent evaporation. We found that a single building block can assemble into two distinct types of polymeric materials, each characterized by unique crosslinking topologies, orders, solubility, and macroscopic properties. The dual dynamic nature of the materials imparts them with intrinsic reconfigurability, such as interfacial repairability and close-loop chemical recyclability.","PeriodicalId":125,"journal":{"name":"Angewandte Chemie International Edition","volume":"75 1","pages":""},"PeriodicalIF":16.6,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142974935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Min-Rui Gao, Ye-Cheng Li, Xiao-Long Zhang, Xiao-Lin Tai, Xue-Peng Yang, Peng-Cheng Yu, Shi-Chen Dong, Li-Ping Chi, Zhi-Zheng Wu, Yu-Cai Zhang, Shu-Ping Sun, Pu-Gan Lu, Lei Zhu, Fei-Yue Gao, Yue Lin
Electrolysis of carbon dioxide (CO2) in acid offers a promising route to overcome CO2 loss in alkaline and neutral electrolytes, but requires concentrated alkali cations (typical ≥3 M) to mitigate the trade-off between low pH and high hydrogen evolution reaction (HER) rate, causing salt precipitation. Here we report a strategy to resolve this problem by introducing tensile strain in a copper (Cu) catalyst, which can selectively reduce CO2 to valuable multicarbon products, particularly ethylene, in a pH 1 electrolyte with 1 M potassium ions. We find that the tension-strained Cu creates an electron-rich surface that concentrates diluted potassium ions, contributing to CO2 activation and HER suppression. With this catalyst, we show constant ethylene Faradaic efficiency (FE) of 44.3% over 100 hours at 400 mA cm-2 and a cell voltage of 3.1 volts in a proton-exchange membrane electrolyser. Moreover, selective electrosynthesis of ethylene oxide using the as-produced ethylene was demonstrated in an integrated system.
{"title":"Highly Tension-Strained Copper Concentrates Diluted Cations for Selective Proton-Exchange Membrane CO2 Electrolysis","authors":"Min-Rui Gao, Ye-Cheng Li, Xiao-Long Zhang, Xiao-Lin Tai, Xue-Peng Yang, Peng-Cheng Yu, Shi-Chen Dong, Li-Ping Chi, Zhi-Zheng Wu, Yu-Cai Zhang, Shu-Ping Sun, Pu-Gan Lu, Lei Zhu, Fei-Yue Gao, Yue Lin","doi":"10.1002/anie.202422054","DOIUrl":"https://doi.org/10.1002/anie.202422054","url":null,"abstract":"Electrolysis of carbon dioxide (CO2) in acid offers a promising route to overcome CO2 loss in alkaline and neutral electrolytes, but requires concentrated alkali cations (typical ≥3 M) to mitigate the trade-off between low pH and high hydrogen evolution reaction (HER) rate, causing salt precipitation. Here we report a strategy to resolve this problem by introducing tensile strain in a copper (Cu) catalyst, which can selectively reduce CO2 to valuable multicarbon products, particularly ethylene, in a pH 1 electrolyte with 1 M potassium ions. We find that the tension-strained Cu creates an electron-rich surface that concentrates diluted potassium ions, contributing to CO2 activation and HER suppression. With this catalyst, we show constant ethylene Faradaic efficiency (FE) of 44.3% over 100 hours at 400 mA cm-2 and a cell voltage of 3.1 volts in a proton-exchange membrane electrolyser. Moreover, selective electrosynthesis of ethylene oxide using the as-produced ethylene was demonstrated in an integrated system.","PeriodicalId":125,"journal":{"name":"Angewandte Chemie International Edition","volume":"42 1","pages":""},"PeriodicalIF":16.6,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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