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Chinese Journal of chemistry 2024年第3期42卷 235-242页

作者： Chun Tang Shengjie Zhang Zhengyu Lu Qian Li Ming Luo Dafa Chen Haiping Xia State Key Laboratory of Physical chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringCollaborative Innovation Center of Chemistry for Energy MaterialsXiamen UniversityXiamenFujian361005 China Shenzhen Grubbs institute and Guangdong Provincial Key Laboratory of Catalysis Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong518055 China

Metallacyclopentadienes are important metallacycles and regarded as intermediates in many reactions,therefore,new methods to achieve them are anticipated.In this study,a formal[3+2]method,through the reactions of an osmapentalyne with benzyl carbanions,was developed.The reactions underwent a nucleophilic attack of carbanions to the Os≡C bond,followed by C—H activation to form the five-membered osmacyclopentadiene ring.Most of the reactions were carried out at room temperature,the substituents on the aromatic rings of benzyl carbanions are diverse,and the resulting products contain an Os—H bond,representing a novel type of 10C-carbolong complexes.This work provides a new convenient route to construct metallacyclopentadienes,which is expected to further promote the development of such a type of substances.

关键词： Metallacyclopentadiene Carbolong chemistry Osmium C–H activation Nucleophilic addition

Delving into the dissimilarities in electrochemical performance and underlying mechanisms for sodium and potassium ion storage in N-doped carbon-encapsulated metallic Cu2Se nanocubes

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Journal of Energy chemistry 2024年第8期95卷 336-347页

作者： Xinyu Wang Yanan Xu Xiaofeng Liu Lei Tan Huaiqiang Gu Xin Du Dan Li College of chemistry Zhengzhou University Green Catalysis Center College of Chemistry Zhengzhou University institute of Theoretical Physics Lanzhou University School of Nuclear Science and Technology Lanzhou University Key Laboratory of Advanced Energy Materials chemistry(Ministry of Education) College of Chemistry Nankai University State Key Laboratory of chemistry and Utilization of Carbon Based Energy Resources College of Chemistry Xinjiang University

The large volumetric variations experienced by metal selenides within conversion reaction result in inferior rate capability and cycling stability,ultimately hindering the achievement of superior electrochemical performance.Herein,metallic Cu2Se encapsulated with N-doped carbon（Cu2Se@NC） was prepared using Cu2O nanocubes as templates through a combination of dopamine polymerization and hightemperature selenization.The unique nanocubic structure and uniform N-doped carbon coating could shorten the ion transport distance,accelerate electron/charge diffusion,and suppress volume variation,ultimately ensuring Cu2Se@NC with excellent electrochemical performance in sodium ion batteries（SIBs） and potassium ion batteries（PIBs）.The composite exhibited excellent rate performance(187.7 mA h g-1at 50 A g-1in SIBs and 179.4 mA h g-1at 5 A g-1in PIBs) and cyclic stability(246,8 mA h g-1at 10 A g-1in SIBs over 2500 cycles).The reaction mechanism of intercalation combined with conversion in both SIBs and PIBs was disclosed by in situ X-ray diffraction（XRD） and ex situ transmission electron microscope（TEM）.In particular,the final products in PIBs of K2Se and K2Se3species were determined after discharging,which is different from that in SIBs with the final species of Na2Se.The density functional theory calculation showed that carbon induces strong coupling and charge interactions with Cu2Se,leading to the introduction of built-in electric field on heterojunction to improve electron mobility.Significantly,the theoretical calculations discovered that the underlying cause for the relatively superior rate capability in SIBs to that in PIBs is the agile Na+diffusion with low energy barrier and moderate adsorption energy.These findings offer theoretical support for in-depth understanding of the performance differences of Cu-based materials in different ion storage systems.

关键词： Cu2Se nanocubes DFT calculations Ion storage mechanism Potassium ion batteries Sodium ion batteries

Illuminating spin-crossover octanuclear metal-organic cages

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Science China chemistry 2024年第4期67卷 1208-1215页

作者： Zhi-Kun Liu Alyona A.Starikova Yu-Xia Li Ke Sun Meng Yu Zi-Shuo Yao Jun Tao Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringLiangxiang CampusBeijing Institute of TechnologyBeijing 102488China institute of Physical and Organic chemistry Southern Federal UniversityRostov-on-Don 344090Russia

Spin-crossover(SCO)materials that reversibly switch between high-and low-spin states have potential for the storage of spin state-relative information,and have gained much attention incorporating secondary physical properties,such as fluorescence and magneto-optical switching.In this study,we synthesized three octanuclear metal-organic cages(MOCs)using tetraphenylethylene-based luminophores,aldehydes,and Fe^(Ⅱ)salts,by subcomponent self-assembly approach,namely[Fe1]-[Fe3].By controlling the ligand-field strength and guest encapsulation,we finely tuned their SCO properties.Among them,MOC[Fe2]displayed nearly complete SCO behavior in the solid state,which is rare for high-nuclearity complexes.We also demonstrated the coupling of SCO with fluorescence emission in these MOCs by using isostructural Zn^(Ⅱ)complexes([Zn1]-[Zn3])as control experiments,for the first time.Theoretical calculations revealed the energy-transfer mechanism between fluorophores and SCOactive centers,which emphasizes the significant contribution of d-d transitions in the interplay between the occurrence of SCO and fluorescence emission.

关键词： metal-organic cages spin crossover fluorescence switching materials DFT calculation

Asymmetric side-chain engineering of organic semiconductor for ultrasensitive gas sensing

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Chinese Chemical Letters 2024年第3期35卷 428-433页

作者： Xiaoying Ma Xiaojuan Dai Lanyi Xiang Jiajun Chang Danfeng Zhi Haozhen Zhao Zhenjie Ni Ye Zou Xike Gao Fengjiao Zhang School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Laboratory of Organic Solids Institute of ChemistryChinese Academy of SciencesBeijing 100190China Key Laboratory of Synthetic and Self-Assembly chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Binzhou institute of Technology Binzhou 256606China

Molecular structure of organic semiconductor plays a critical role in determining the performance and functionality of organic electronic devices,by optimizing the electrical,optical and physicochemical properties.Substituted alkyl chains are fundamental units in tailering the solubility and assemblability,among which the asymmetric properties have been reported as key element for controlling the packing motifs and intrinsic charge transport.Here,we expanded the scope of molecular asymmetry dependent sensing features based on a new series of naphthalene diimides(NDI)-based derivatives substituted with a same branching alkyl chain but various linear-shaped alkyl chains(Cn-).A clear molecular stacking change,from head-to-head bilayer to head-to-tail monolayer packing model,is observed based on the features of anisotropic molecular interactions with the change in the chain length.Most importantly,a unique LUMO level shift of 0.17 eV is validated for NDI-PhC4,providing a record sensitivity up to 150%to 0.01 ppb ammonia,due to the desired molecular reactivity and device amplification properties.These results indicate that asymmetric side-chain engineering opens a route for breath healthcare.

关键词： Organic thin film transistor Asymmetric side chain Gas sensing Molecular stacking Energy level manipulating

Cobalt(Ⅲ)hydride HAT mediated enantioselective intramolecular hydroamination access to chiral pyrrolidines

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Science China chemistry 2024年第6期67卷 2002-2008页

作者： Qi Meng Tao Qin Huanran Miao Ge Zhang Qian Zhang Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun130024China State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Enantioenriched pyrrolidines and derivatives are ubiquitous substructures in compounds of importance to medicinal and biological chemistry.Herein,we report an efficient cobalt-catalyzed intramolecular asymmetric hydroamination reaction that produces chiral pyrrolidines with good to excellent yield and enantiocontrol.Compared with previously reported radicalinvolved methodologies for enantioenriched pyrrolidines,these conditions feature two elegant versatilities,enabling(1)the use of cobalt-catalyzed hydrogen atom transfer(HAT)to generate organocobalt intermediates that bring radical reaction to organometallic chemistry,and(2)enantioselective intramolecular C-N bond forging through an S_(N)2-like displacement involving dynamic kinetic resolution(DKR).This approach provides a new alternative and efficient methodology for enantioselective radical-involved C-N bond construction that can be used in the synthesis of both chiral pyrrolidines and homologous nitrogen heterocycles.

关键词： asymmetric catalysis radical hydroamination cobalt catalysis hydrogen atom transfer

Heterocatalytic ethylene methoxycarbonylation via a pseudo-hydride pathway over Pt1/MoS2

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Science China chemistry 2024年第8期67卷 2427-2428页

作者： Bo-Hang Zhao Bin Zhang institute of Molecular Plus Department of Chemistry School of Science Tianjin University

Ethylene (C2H4) methoxycarbonylation (EMC) with CO and methanol (CH3OH) to methyl propanoate (MP) is industrially important due to its 100% atom efficiency [1].However, the heavy reliance on homogeneous Pd-based catalysts and strong acid media over commercial EMC processes still causes economic and environmental concerns [2]. At present, supported single-atom catalysts (SACs) can serve as bridges for accessing homogeneous catalysts in traditional heterogeneous catalytic processes.

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Defect mediated losses and degradation of perovskite solar cells:Origin impacts and reliable characterization techniques

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Journal of Energy chemistry 2024年第7期94卷 217-253页

作者： Himangshu Baishy Ramkrishna Das Adhikari Mayur Jagdishbhai Patel Deepak Yadav Tapashi Sarmah Mizanur Alam Manab Kalita Parameswar Krishnan lyer Centre for Nanotechnology Indian Institute of Technology GuwahatiGuwahati 781039AssamIndia Department of chemistry Indian Institute ofTechnology GuwahatGuwahati739AssamIndi

The rapid advancement of halide-based hybrid perovskite materials has garnered significant research attention,particularly in the domain of photovoltaic technology.Owing to their exceptional optoelec-tronic properties,they demonstrated power conversion efficiency(PcE)of over 25%in single junction solar cells.Despite the notable progress in PCE over the past decade,the inherent high defect density pre-senting in perovskite materials gives rise to several loss mechanisms and associated ion migration in per-ovskite solar cells(PsCs)during operational conditions.These factors collectively contribute to a significant stability challenge in PsCs,placing their longevity far behind for commercialization.While numerous reports have explored defects,ion migration,and their impacts on device performance,a com-prehensive correlation between the types of defects and the degradation kinetics of perovskite materials and PsCs has been lacking.In this context,this review aims to provide a comprehensive overview of the origins of defects and ion migration,emphasizing their correlation with the degradation kinetics of per-ovskite materials and PsCs,leveraging reliable characterization techniques.Furthermore,these charac-terization techniques are intended to comprehend loss mechanisms by different passivation approaches to enhance the durability and PCE of PSCs.

关键词： Perovskite solar cells Defects lon migration Degradation Stability

Controlling hydrogenation of C=C and C=O bonds in cinnamaldehyde using Pt1/Ni and Pt1/Co single-atom alloy catalysts

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Rare Metals 2024年第6期43卷 2859-2868页

作者： Huan-Shi Lan Yi-Da Yang Qing-Di Sun Hao Zhang Ying Zhang Qian He Ran Chen Guo-Yi Bai Xiao-Hui He Hong-Bing Ji School of chemistry and Chemical Engineering Guangxi University Key Laboratory of Bioinorganicand Synthetic chemistry of Ministry of Education Fine Chemical Industry Research InstituteSchool of ChemistryIGCMESun Yat-sen University UBFC CNRSENSMMFEMTO-ST Institute College of chemistry and Materials Science Hebei University State Key Laboratory Breeding Base of Green-Chemical Synthesis Technology Institute of Green Petroleum Processing and Light Hydrocarbon ConversionCollege of Chemical EngineeringZhejiang University of Technology

Selective hydrogenation of C=C and C=O bonds in cinnamaldehyde (CAL) to produce desired products is a challenging task due to the complex conjugate system of the two unsaturated functional groups.In this study,a simple ball milling method is presented for synthesizing Pt-based single-atom alloy catalysts (SAAs) that can function as a control switch for the selective hydrogenation of CAL into highly valuable products.

关键词： SELECTIVE HYDROGENATION CHEMOSELECTIVE HYDROGENATION NANOPARTICLES GENERATION EFFICIENT FE CO

Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： Feng Ren Zhuang-Zhuang Liang Ming-Xin Niu Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic systems.The new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

Nanofluidic memristor based on the elastic deformation of nanopores with nanoparticle adsorption

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National Science Review 2024年第4期11卷 46-54页

作者： Xi Zhou Yuanyuan Zong Yongchang Wang Miao Sun Deli Shi Wei Wang Guanghua Du Yanbo Xie Department of chemistry and Chemical Engineering Northwestern Polytechnical University School of Physical Science and Technology Northwestern Polytechnical University School of Aeronautics and institute of Extreme Mechanics Northwestern Polytechnical University institute of Modern Physics Chinese Academy of Sciences

The memristor is the building block of neuromorphic computing. We report a new type of nanofluidic memristor based on the principle of elastic strain on polymer nanopores. With nanoparticles absorbed at the wall of a single conical polymer nanopore, we find a pinched hysteresis of the current within a scanning frequency range of 0.01–0.1 Hz, switching to a diode below 0.01 Hz and a resistor above 0.1 Hz. We attribute the current hysteresis to the elastic strain at the tip side of the nanopore, caused by electrical force on the particles adsorbed at the inner wall surface. Our simulation and analytical equations match well with experimental results, with a phase diagram for predicting the system transitions. We demonstrate the plasticity of our nanofluidic memristor to be similar to a biological synapse. Our findings pave a new way for ionic neuromorphic computing using nanofluidic memristors.

关键词： nanofluidics memristor neurocomputing elastic deformation