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Regioselective C-C bond cleavage/aminocarbonylation cascade under copper catalysis

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Science China chemistry 2024年第11期67卷 3798-3806页

作者： Qi-Chao Shan Yan Zhao Yong Wu Hong-Fei Liu Xin-Hua Duan Li-Na Guo department of chemistry School of Chemistry Energy Research Center of Energy Storage Materials and Devices Ministry of EducationXi'an Jiaotong University State Key Laboratory of applied Organic chemistry Lanzhou University

A regioselective C-C bond cleavage/aminocarbonylation cascade is presented. In recent years, tremendous progress has been made in the alkoxyl radical-mediated C-C bond cleavage of unstrained monocarbocycles. In contrast, the deconstruction and functionalization of bicyclic skeletons has been less developed and has mainly focused on the ring expansion process. Inspired by the aromatization-driven C-C bond cleavage, here we demonstrate a ring-opening/aminocarbonylation cascade under copper catalysis, in which the formation of a stable γ-lactam or succinimide skeleton reverses the selectivity of C-C cleavage. Remarkably, the photo and thermal assistance is not required when the succinimide skeleton is formed during the ring opening process. DFT calculations revealed that this unexpected ring-opening process is thermodynamically and kinetically favourable.

关键词： C-C bond cleavage controllable regioselectivity aminocarbonylation bicyclic alkoxy radical

Emerging two-dimensional Mo-based materials for rechargeable metal-ion batteries:Advances and perspectives

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Journal of Energy chemistry 2024年第2期89卷 487-518,I0012页

作者： Qingqing Ruan Yuehua Qian Mengda Xue Lingyun Chen Qichun Zhang department of applied chemistry School of Chemistry and Chemical EngineeringChongqing UniversityChongqing 401331China department of materials Science and Engineering City University of Hong Kong999077Hong KongChina

With the rapid development of rechargeable metal-ion batteries(MIBs)with safety,stability and high energy density,significant efforts have been devoted to exploring high-performance electrode *** recent years,two-dimensional(2D)molybdenum-based(Mo-based)materials have drawn considerable attention due to their exceptional characteristics,including low cost,unique crystal structure,high theoretical capacity and controllable chemical ***,like other transition metal compounds,Mo-based materials are facing thorny challenges to overcome,such as slow electron/ion transfer kinetics and substantial volume changes during the charge and discharge *** this review,we summarize the recent progress in developing emerging 2D Mo-based electrode materials for MIBs,encompassing oxides,sulfides,selenides,*** introducing the crystal structure and common synthesis methods,this review sheds light on the charge storage mechanism of several 2D Mo-based materials by various advanced characterization *** latest achievements in utilizing 2D Mo-based materials as electrode materials for various MIBs(including lithium-ion batteries(LIBs),sodium-ion batteries(SIBs)and zinc-ion batteries(ZIBs))are discussed in ***,the modulation strategies for enhancing the electrochemical performance of 2D Mo-based materials are highlighted,focusing on heteroatom doping,vacancies creation,composite coupling engineering and nanostructure ***,we present the existing challenges and future research directions for 2D Mo-based materials to realize high-performance energy storage systems.

关键词： Molybdenum-based materials Two-dimensional materials Lithium-ion batteries Sodium-ion batteries Zinc-ion batteries

Polypyride intercalation boosting the kinetics and stability of V_(3)O_(7)·H_(2)O cathodes for aqueous zinc-ion batteries

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Journal of Energy chemistry 2024年第10期97卷 361-370,I0007页

作者： Qingqing He Jie Bai Mengda Xue Yanxin Liao Huayu Wang Mujun Long Lingyun Chen department of applied chemistry School of Chemistry and Chemical EngineeringChongqing UniversityChongqing 41331China Laboratoryof materials and Metallurgy Cllege of Materials Science and EngineeringChongqing UniversityChongqing 400044Chin

V_(3)O_(7)·H_(2)O(VO)is a high capacity cathode material in the field of aqueous zinc ion batteries(AZIBs),but it is limited by slow ion migration and low electrical *** this paper,polypyridine(PPyd)intercalated VO with nanoribbon structure was prepared by a simple in-situ pre-intercalation,which is noted *** total density of states(TDOS)shows that after the pre-intercalation of PPyd,an intermediate energy level appears between the valence band and conduction band,which provides a step that can effectively reduce the band gap and enhance the electron ***,the density functional theory(DFT)results found that Zn^(2+)is more easily de-intercalated from the V-O skeleton,which proves that the embeddedness of PPyd improves the diffusion kinetics of Zn^(2+).Electrochemical studies have shown that VO-PPyd cathode materials exhibit excellent rate performance(high specific capacity of 465 and 192 mA h g^(-1)at 0.2 and 10 A g^(-1),respectively)and long-term cycling performance(92.7%capacity retention rate after 5300 cycles),due to their advantages in structure and *** importantly,the energy density of VO-PPyd//Zn at 581 and 5806 W kg^(-1)is 375 and 247 W h kg^(-1),***-PPyd exhibits excellent electrochemical properties compared to previously reported vanadium based cathodes,which makes it highly competitive in the field of high-performance cathode materials of AZIBs.

关键词： V_(3)O_(7)·H_(2)O Polypyridine Ion migration Electrical conductivity Aqueous zinc ion batteries DFT calculation

Topological Structure-Modulated Collagen Carbon as Two-in-One Energy Storage Configuration toward Ultrahigh Power and Energy Density

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Energy & Environmental materials 2024年第2期7卷 18-29页

作者： Li Yuan Wenlong Cai Yunhong Wei Yiran Pu Can Liu Yun Zhang Hao Wu College of materials Science and Engineering Sichuan UniversityChengdu 610065China department of applied chemistry University of Science and Technology of ChinaHefei 230026China

Efficient energy storage devices with suitable electrode materials,that integrate high power and high energy,are the crucial requisites of the renewable power source,which have unwrapped new possibilities in the sustainable development of energy and the ***,a facile collagen microstructure modulation strategy is proposed to construct a nitrogen/oxygen dual-doped hierarchically porous carbon fiber with ultrahigh specific surface area(2788 m^(2)g^(-1))and large pore volume(4.56 cm^(3)g^(-1))via local microfibrous breakage/disassembly of natural structured *** operando spectroscopy and density functional theory unveil that the dual-heteroatom doping could effectively regulate the electronic structure of carbon atom framework with enhanced electric conductivity and electronegativity as well as decreased diffusion resistance in favor of rapid pseudocapacitive-dominated Li^(+)-storage(353 mAh g^(-1)at 10 A g^(-1)).Theoretical calculations reveal that the tailored micro-/mesoporous structures favor the rapid charge transfer and ion storage,synergistically realizing high capacity and superior rate performance for NPCF-H cathode(75.0 mAh g^(-1)at 30 A g^(-1)).The assembled device with NPCF-H as both anode and cathode achieves extremely high energy density(200 Wh kg^(-1))with maximum power density(42600 W kg^(-1))and ultralong lifespan(80%capacity retention over 10000 cycles).

关键词： collagen carbon energy storage device theoretical calculations topological structure modulation ultrahigh power and energy density

Emerging perovskite materials for supercapacitors:Structure,synthesis,modification,advanced characterization,theoretical calculation and electrochemical performance

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Journal of Energy chemistry 2024年第2期89卷 41-70,I0003页

作者： Yuehua Qian Qingqing Ruan Mengda Xue Lingyun Chen department of applied chemistry School of Chemistry and Chemical EngineeringChongqing UniversityChongqing 401331China

As a new generation electrode materials for energy storage,perovskites have attracted wide attention because of their unique crystal structure,reversible active sites,rich oxygen vacancies,and good *** this review,the design and engineering progress of perovskite materials for supercapacitors(SCs)in recent years is ***,the review will focus on four types of perovskites,perovskite oxides,halide perovskites,fluoride perovskites,and multi-perovskites,within the context of their intrinsic structure and corresponding electrochemical performance.A series of experimental variables,such as synthesis,crystal structure,and electrochemical reaction mechanism,will be carefully analyzed by combining various advanced characterization techniques and theoretical *** applications of these materials as electrodes are then featured for various ***,we look forward to the prospects and challenges of perovskite-type SCs electrodes,as well as the future research direction.

关键词： Perovskite Modification engineering Oxygen vacancy Theoretical calculation methodology Supercapacitor

Multicolor circularly polarized phosphorescence of axially chiral binuclear platinum(Ⅱ) complexes

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Science China chemistry 2024年第11期67卷 3757-3766页

作者： Jintong Song Rui Zeng Hui Xiao Hailiang Ni Zong-Xiang Xu Haifeng Xiang College of chemistry and materials Science Sichuan Normal University department of chemistry Southern University of Science and Technology College of chemistry Sichuan University

D-A charge transfer, including through-bond charge transfer and through-space charge transfer between two different electron donors（D） and electron acceptors（A）, is a fundamental and powerful tool to tune the optical properties of organic dyes. Herein,we demonstrate a unique strategy to tune phosphorescence and circularly polarized luminescence properties of axially chiral binuclear Pt（Ⅱ） complexes through long-range charge transfer, even though these molecules have two totally identical segments on either side of the chiral core. The presence of axial chirality would break not only the symmetry of molecular structure and π-conjugation system but also the symmetry of charge distribution for long-range charge transfer. These binaphthyl-based Pt（Ⅱ）complexes bearing coordinated atoms far away from chiral axis exhibit no Pt-Pt interactions but colorful concentrationdependent phosphorescence with quantum yield up to 86.4% and could be applied as emitters in highly efficient solutionprocessed organic light-emitting diodes to achieve luminance, luminance efficiency, power efficiency, external quantum efficiency, and asymmetry factor up to 8.94 × 10～3cd m-2, 41.9 cd A-1, 18.8 lm W-1, 12.6% and 2.98 × 10-3, respectively. Therefore,the present work affords a new and simple way to utilize the inherently asymmetric advantage of chirality for the design of D-Abased organic dyes.

关键词： Pt(II) complexes organic light-emitting diodes circularly polarized phosphorescence axial chirality

Facile Synthesis of Polyisothioureas via Alternating Copolymerization of Aziridines and Isothiocayanates

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Chinese Journal of Polymer Science 2024年第3期42卷 292-298,I0005页

作者： Hao-Tian Zhang Ming-Xin Niu Qi Zhang Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China department of materials Science and Engineering Jilin UniversityChangchun 130025China School of applied chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer's side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions(11 examples). The structures of obtained polyisothioureas were fully characterized with ^(1)H-NMR, ^(13)C-NMR, and ^(1)H-^(13)C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of nextgeneration functional plastics.

关键词： Polyisothioureas Alternative copolymer Aziridines Isothiocayanates

Template-Induced Graphitic Nanodomains in Nitrogen-Doped Carbons Enable High-Performance Sodium-Ion Capacitors

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Energy & Environmental materials 2024年第4期7卷 295-303页

作者： Chun Li Zihan Song Minliang Liu Enrico Lepre Markus Antonietti Junwu Zhu Jian Liu Yongsheng Fu Nieves López-Salas Key Laboratory for Soft chemistry and Functional materials of Ministry of Education Nanjing University of Science and Technology Colloid chemistry department Max Planck Institute of Colloids and Interfaces School of Engineering Faculty of Applied Science University of British Columbia

Sodium-ion capacitors (SICs) have great potential in energy storage due to their low cost,the abundance of Na,and the potential to deliver high energy and power *** article demonstrates a template-assisted method to i... 详细信息

关键词： anode graphitic nanodomains N-doped carbons sodium-ion capacitor template

Molecule aging induced by electron attacking

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Journal of Energy chemistry 2024年第6期93卷 519-525,I0013页

作者： Ping Song Yining Dong Xue Gong Mingbo Ruan Baoxin Ni Xuanhao Mei Kun Jiang Weilin Xu State Key Laboratory of Electroanalytical chemistry and Jilin Province Key Laboratory of Low Carbon Chemical Power Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022JilinChina School of applied chemistry and Engineering University of Science and Technology of Chin1Hefei 230026AnhuiChina Shanghai Key Laboratory of Molecular Catalysis and Innovative materials Collaborative Innovation Center of Chemistry for Energy MaterialsDepartment of ChemistryFudan UniversityShanghai 200438China

Here we propose a new concept of"molecule aging":with some special treatment,a molecule could be"aged"by losing some unknown tiny particles or pieces from atoms in the molecule,Such"aging"or loss of unknown tiny particles does not change apparently its molecular structure or chemical composition,but some physicochemical properties could be changed *** further confirm such"molecule aging"via a long-term electron attacking to age water(H_(2)O)*** IR spectra show no structural difference between the fresh water and the aged one,while the NMR spectra show that the electron attacking can decrease the size of water *** facts indicate that the electron attacking indeed can"affect"the structure of water molecule slightly but without damaging to its basic molecule *** exploration reveals that the hydrogen evolution reaction(HER)activity of the aged water molecule is lower than the fresh water on the same Pt/C *** density functional theory calculations indicate that the shortened O-H bond in H_(2)O indeed can present lower HER activity,so the observed size decrease of water clusters from NMR probably could be attributed to the shortening of O-H bond in water *** results indicate significantly that the molecule aging can produce materials with new functions for new possible applications.

关键词： Aging of molecules Electron attacking Full width at half maxima Hydrogen evolution reaction