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Journal of Pharmaceutical Analysis 2024年第5期14卷 772-774页

作者： Lei Yang Yan Wang Zhao Wang Meiyu Cui Ruolan Jin Hai-Bo Shang Donghao Li College of Pharmacy Yanbian UniversityYanjiJilin133002China department of Chemistry Interdisciplinary Program of Biological Functional MoleculesCollege of Integration ScienceYanbian UniversityYanjiJilin133002China

Owing to its high sensitivity,selectivity,and accuracy,liquid chromatography coupled with mass spectrometry(LC-MS)is commonly employed to screen,confirm,and quantify impurities in drugs[1].However,LC-MS has certain drawbacks such as complicated pretreatment steps,long analysis time,large consumption of organic solvents,high maintenance costs,and,most notably,the need for high-pressure pumps and compatible hardware because of the high column backpressure[2].In this study,a two-dimensional(2D)microscale carbon fiber(CF)/active carbon fiber(ACF)system combined with a quadrupole time-of-flight high-resolution mass spectrometry(2DmCFs-QTOF-HRMS)system was developed to rapid screening impurities in the typical three generations of oral cephalosporins,i.e.,cephalexin tablets(CPXTs),cefuroxime axetil tablets(CFATs),and cefixime tablets(CFXTs)(Fig.S1).The“fuzzy chromatographic separation”sample pretreatment method separates complex samples into high-,medium-,and weak-polar fractions for successive detection of MS,achieving effective reduction of the ion suppression effect in electrospray ionization(ESI)-MS and improving the MS detection *** to high performance liquid chromatography(HPLC)-MS,this method has distinct advantages such as less organic solvent consumption(1.5 mL),shorter separation and analysis times(5 min),more information on impurities,and high reproducibility.

关键词： system carbon tablets

Confined Mn^(2+) enables effective aerobic oxidation catalysis

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Science China Chemistry 2024年第5期67卷 1545-1553页

作者： Desheng Yuan Sicong Ma Xiao Kong Chi Zhang Lin Chen Chengsheng Yang Lihua Wang Zhen Liu Lin Ye Yongmei Liu Rui Ma Zhi-Pan Liu Yifeng Zhu Yong Cao Xinhe Bao department of Chemical Physics University of Science and Technology of ChinaHefei 230026China department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsCollaborative Innovation Center of Chemistry for Energy MaterialsFudan UniversityShanghai 200438China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Institute of Advanced Fluorine-Containing materials Zhejiang Normal UniversityJinhua 321004China State Key Laboratory of Catalysis National Laboratory for Clean EnergyCollaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Effective and mild activation of O_(2) is essential but challenging for aerobic oxidation. In heterogeneous catalysis, high-valence manganese oxide(e.g., +4) is known to be active for the oxidation, whereas divalent MnO is ineffective due to its limited capacity to supply surface oxygen and its thermodynamically unstable structure when binding O_(2) in reaction conditions. Inspired by natural enzymes that rely on divalent Mn^(2+), we discovered that confining Mn^(2+) onto the Mn_(2)O_(3) surface through a dedicated calcination process creates highly active catalysts for the aerobic oxidation of 5-hydroxymethylfurfural, benzyl alcohol, and *** Mn_(2)O_(3)-confined Mn^(2+) is undercoordinated and efficiently mediates O_(2) activation, resulting in 2–3 orders of magnitude higher activity than Mn_(2)O_(3) alone. Through low-temperature infrared spectroscopy, we distinguished low-content Mn^(2+) sites at Mn_(2)O_(3) surface, which are difficult to be differentiated by X-ray photoelectron spectroscopy. The combination of in-situ energydispersive X-ray absorption spectroscopy and X-ray diffraction further provides insights into the formation of the newly identified active Mn^(2+) sites. By optimizing the calcination step, we were able to increase the catalytic activity threefold *** finding offers promising frontiers for exploring active oxidation catalysts by utilizing the confinement of Mn^(2+)and oftenignored calcination skills.

关键词： confinement catalysis manganese oxide aerobic oxidation divalent Mn^(2+) operando spectroscopies

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Computational design of bimetallic Tm_(2)@g-C_(9)N_(4)electrocatalysts for enhanced CO reduction toward C_(2)products

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Chinese Chemical Letters 2024年第7期35卷 484-490页

作者： Jiajun Wang Guolin Yi Shengling Guo Jianing Wang Shujuan Li Ke Xu Weiyi Wang Shulai Lei Tianjin Key Laboratory of Structure and Performance for Functional molecules College of ChemistryTianjin Normal UniversityTianjin 300387China department of Chemical Physics&Hefei National Laboratory for Physical Sciences at Microscale University of Science and Technology of ChinaHefei 230026China Hubei Key Laboratory of Low Dimensional Optoelectronic materials and Devices Hubei University of Arts and ScienceXiangyang 441053China Hubei Longzhong Laboratory Xiangyang 441053China

Electrochemical CO reduction(ECOR)as a potential strategy for producing valuable chemicals and fuels has captured substantial ***,the currently available electrocatalysts suffer from poor selectivity and low Faradaic efficiency,limiting their industrial ***,we systematically investigate the potential of homonuclear bimetallic electrocatalysts,Tm_(2)@C_(9)N_(4)(TM=Fe,Co,Ni,and Cu),for the ECOR through extensive density functional theory *** findings suggest that all four proposed monolayers exhibit exceptional stability,making them highly suitable for experimental synthesis and practical ***,these transition-metal dual atoms anchored on C_(9)N_(4)monolayers show great potential in facilitating the production of high-value C_(2)products,such as C_(2)H_(5)OH and C_(2)H_(4),due to the significantly low limiting potentials(-0.06~-0.46 V)and small kinetic energy barriers(0.54–1.08 eV)for the CO coupling ***,with the exception of Ni_(2)@C_(9)N_(4),these bimetallic catalysts demonstrate the impressive suppression of the competitive hydrogen evolution reaction(HER),leading to a high selectivity for C_(2)products in *** predictions would accelerate the development of high-performance C_(9)N_(4)-based dual-atom catalysts for the ECOR.

关键词： C_(9)N_(4)monolayer Double-atom catalysts CO electroreduction Multi-carbon products Density functional theory

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Biomimetic design of highly flexible metal oxide nanofibrous membranes with exceptional mechanical performance for superior phosphopeptide enrichment

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Nano Research 2024年第5期17卷 4270-4278页

作者： Xue Mao Zhen-Zhen Li Dong-Lian Hao Wei-Dong Han Gao-Peng Li Yao-Yu Wang Kun Zhang School of Textile Science and Engineering Key Laboratory of Functional Textile Material and Product(Ministry of Education)Xi’an Polytechnic UniversityXi’an 710048China Key Laboratory of Magnetic molecules&Magnetic Information materials of the Ministry of Education School of Chemistry&Material ScienceShanxi Normal UniversityTaiyuan 030031China department of Clinical Laboratory The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004China Shanghai iProteome Biotechnology Co. LtdShanghai 201210China College of Chemistry&materials Science Northwest UniversityXi'an 710127China

Developing free-standing and mechanical robust membrane materials capable of superior enrichment of phosphopeptides for analyzing and identifying the specific phosphoproteome of cancer cells is significant in understanding the molecular mechanisms of cancer development and exploring new therapeutic approaches,but still a significant challenge in materials *** this end,we firstly constructed highly flexible ZrTiO_(4) nanofibrous membranes(NFMs)with excellent mechanical stability through a cost-effective and scalable electrospinning and subsequent calcination ***,to further increase the enrichment capacity of the phosphopeptide,the biomimetic TiO_(2)@ZrTiO_(4) NFMs with root hair or leaf like branch microstructure are developed by the hydrothermal post-synthetic modification of ZrTiO_(4) NFMs through growing unfurling TiO_(2) nanosheets onto the ZrTiO_(4) ***,remarkable flexibility and mechanical stability enable the resulting TiO_(2)@ZrTiO_(4) NFMs excellent practicability,while the biomimetic microstructure allows it outstanding enrichment ability of the phosphopeptide and identification ability of the specific phosphoproteins in the digest of cervical cancer ***,6770 phosphopeptides can be enriched by TiO_(2)@ZrTiO_(4) NFMs(2205 corresponding phosphoproteins can be identified),and the value is much higher than that of ZrTiO_(4) NFMs(6399 phosphopeptides and 2132 identified phosphoproteins)and commercial high-performance TiO_(2) particles(4525 phosphopeptides and 1811 identified phosphoproteins).These results demonstrate the super ability of TiO_(2)@ZrTiO_(4) NFMs in phosphopeptide enrichment and great potential for exploring the pathogenesis of cancer.

关键词： inorganic nanofibers flexible ceramic nanofibrous membranes biomimetic materials exceptional mechanical performance flexibility

Metal to insulator transition for conducting polymers in plasmonic nanogaps

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Light(Science & Applications) 2024年第1期13卷 23-32页

作者： Yuling Xiong Rohit Chikkaraddy Charlie Readman Shu Hu Kunli Xiong Jialong Peng Qianqi Lin Jeremy J.Baumberg NanoPhotonics Centre Cavendish LaboratoryDepartment of PhysicsUniversity of CambridgeCambridgeCB30HEUK School of Physics&Astronomy University of BirminghamEdgbastonBirminghamUK College of Advanced Interdisciplinary Studies and Hunan Provincial Key Laboratory of Novel Nano-Optoelectronic Information materials and Devices National University of Defense TechnologyChangshaChina Hybrid materials for Opto-Electronics Group Department of Molecules and MaterialsMESA+Institute for NanotechnologyMolecules Center and Center for Brain-Inspired Nano SystemsFaculty of Science and TechnologyUniversity of TwenteEnschedeNetherlands

Conjugated polymers are promising material candidates for many future applications in flexible displays, organic circuits, and sensors. Their performance is strongly affected by their structural conformation including both electrical and optical anisotropy. Particularly for thin layers or close to crucial interfaces, there are few methods to track their organization and functional behaviors. Here we present a platform based on plasmonic nanogaps that can assess the chemical structure and orientation of conjugated polymers down to sub-10 nm thickness using light. We focus on a representative conjugated polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), of varying thickness (2-20 nm) while it undergoes redox in situ. This allows dynamic switching of the plasmonic gap spacer through a metal-insulator transition. Both dark-field (DF) and surface-enhanced Raman scattering (SERS) spectra track the optical anisotropy and orientation of polymer chains close to a metallic interface. Moreover, we demonstrate how this influences both optical and redox switching for nanothick PEDOT devices.

关键词： transition insulator conjugated

Subnanometric bimetallic Pt–Pd clusters in zeolites for efficient hydrogen production and selective tandem hydrogenation of nitroarenes

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Science China Chemistry 2024年第9期67卷 2911-2917页

作者： Jiafu Li Tao Cai Yanran Feng Xia Liu Ning Wang Qiming Sun Institute of Sustainable Energy and Resources College of Chemistry and Chemical Engineering Key Laboratory of Shandong Provincial Universities for Functional Molecules and Materials Qingdao University Innovation Center for Chemical Sciences College of Chemistry Chemical Engineering and Materials Science Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow University

The solvolysis of ammonia borane（AB） and the hydrogenation of nitroarenes represent significant reactions for hydrogen generation and value-added chemical synthesis. The strategic engineering of the catalysts is imperative for surmounting obstacles associated with their stability and catalytic efficiency. In this work, subnanometric bimetallic Pt–Pd clusters were encapsulated within silicalite-1（S-1） zeolites through a ligand-protected in-situ hydrothermal synthesis method. The synergetic effect of bimetallic composition and zeolite confinement markedly enhances the catalytic performance of representative Pt0.5Pd0.5@S-1-H catalyst, affording exceptional turnover frequency（TOF） values of 1,043 and 573 molH2molmetal-1min-1for AB hydrolysis and methanolysis at ambient conditions, respectively, surpassing most of the state-of-the-art Pt-based *** and isotopic experiments reveal that the bimetallic catalytic system remarkably boosts the O–H cleavage of water,thereby facilitating the H2production from AB hydrolysis. Remarkably, a conspicuous synergistic effect is demonstrated in the shape-selective tandem hydrogenation of nitroarenes, with the bimetallic catalyst facilitating both AB hydrolysis and nitroarene hydrogenation, giving a high TOF value of 1,260 h-1under atmospheric pressure. This study not only demonstrates the effectiveness of bimetallic nanocatalysts encapsulated in zeolites for hydrogen production from chemical hydrogen storage materials, but also paves the way for the design of catalysts with multifunctional active sites capable of synergistically promoting tandem catalytic processes.

关键词： subnanometer bimetallic cluster zeolite synergistic effect ammonia borane solvolysis selective tandem hydrogenation

Universal insertion of molecules in ionic compounds under pressure

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National Science Review 2024年第1期11卷 120-128页

作者： Feng Peng Yanming Ma Chris J.Pickard Hanyu Liu Maosheng Miao College of Physics and Electronic Information Luoyang Normal University department of Chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard materials & Key Laboratory of Material Simulation Methods and Software of Ministry of Education College of Physics Jilin University International Center of Future Science Jilin University department of materials Science & Metallurgy University of Cambridge Advanced Institute for materials Research Tohoku University department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, N2, CO2, NH3, H2O and CH4may react with NaC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. These molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding Na and Cl ions. In contrast, the most stable molecule among all examples, N2, is found to transform into cyclo-N5-anions while reacting with NaC l under high pressures. It provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. This surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior

A dynamically stable self-healable wire based on mechanical±electrical coupling

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National Science Review 2024年第3期 250-258页

作者： Shuo Wang Zhaofeng Ouyang Shitao Geng Yan Wang Xiaoju Zhao Bin Yuan Xiao Zhang Qiuchen Xu Chengqiang Tang Shanshan Tang Han Miao Huisheng Peng Hao Sun Frontiers Science Center for Transformative molecules School of Chemistry and Chemical EngineeringZhangjiang Institute for Advanced Studyand Key Laboratory of Green and High-End Utilization of Salt Lake Resources(Chinese Academy of Sciences)Shanghai Jiao Tong University State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science Institute of Fiber Materials and Devices and Laboratory of Advanced MaterialsFudan University School of materials Science and Engineering East China University of Science and Technology

The rise in wearable electronics has witnessed the advancement of self-healable wires, which are capable of recovering mechanical and electrical properties upon structural damage. However, their highly fluctuating electrical resistances in the range of hundreds to thousands of ohms under dynamic conditions such as bending, pressing, stretching and tremoring may seriously degrade the precision and continuity of the resulting electronic devices, thus severely hindering their wearable applications. Here, we report a new family of self-healable wires with high strengths and stable electrical conductivities under dynamic conditions, inspired by mechanical–electrical coupling of the myelinated axon in nature. Our self-healable wire based on mechanical–electrical coupling between the structural and conductive components has significantly improved the electrical stability under dynamic scenarios, enabling precise monitoring of human health status and daily activities, even in the case of limb tremors from simulated Parkinson's *** mechanical–electrical coupling strategy opens a new avenue for the development of dynamically stable electrodes and devices toward real-world wearable applications.

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Rhodium-catalyzed addition reactions of benzylic C–H bonds to cyclic N-sulfonyl ketimines viaπ-coordination

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Chinese Chemical Letters 2024年第3期35卷 287-291页

作者： Yuntong Li Hang Shi department of Chemistry Zhejiang UniversityHangzhou 310027China Key Laboratory of Precise Synthesis of Functional molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Mannich-type reactions are a widely used method for the synthesis of amines due to the readily availability of nucleophiles and ***,the inclusion of alkylarenes instead of active carbon pronucleophiles such as aldehydes and ketones in these addition reactions has been a challenge due to the inherent difficulty of benzylic *** this study,we present a novel approach for the construction of N-sulfonyl amines via rhodium-catalyzed addition of unbiased benzylic C–H bonds to cyclic N-sulfonyl ketamines throughπ-*** strategy enables the synthesis of a diverse range of N-sulfonyl amines,and subsequent diversification of the addition products showcases the synthetic potential of this protocol.

关键词： Benzylic deprotonation Cyclic N–sulfonyl ketimines π-Coordination Mannich-type addition Rhodium catalysis

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Insight into the mechanism of 5-hydroxymethylfurfural electroreduction to 2,5-bis(hydroxymethyl)furan over Cu anchored N-doped carbon nanosheets

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Nano Research 2024年第9期17卷 7991-7999页

作者： Haoran Wu Xinwei Chen Haishan Xu Runlu Yang Xin Wang Junying Chen Zhenbing Xie Liang Wu Yiyong Mai School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgeingShanghai Jiao Tong UniversityShanghai 200240China department of Chemistry Tangshan Normal UniversityTangshan 063000China

Design of non-noble metal electrocatalysts for biomass conversion to high-value chemicals and understanding the related catalytic mechanisms are of profound significance but have remained a major ***,we developed a novel biomass-derived electrocatalyst(denoted as Cu/NC),featuring with electron-deficient copper nanoparticles anchored on N-doped carbon nanosheets,for the electrochemical reduction of 5-hydroxymethylfurfural(HMF)to 2,5-bis(hydroxymethyl)furan(BHMF,a vital precursor of functional polymers).The optimized Cu/NC electrocatalyst exhibited an excellent performance with high Faradaic efficiency(89.5%)and selectivity(90.8%)of BHMF at a low concentration of HMF(18.1 mM).Even at a very high HMF concentration(108.6 mM),the Faraday efficiency and selectivity of BHMF could still reach 74.8%and 81.1%,*** performance approached those of the reported noble metal-based *** study revealed that the N doping in the Cu/NC catalyst could regulate the electronic structure of Cu,strengthening the adsorption of the HMF carbonyl group,and thus boosting the selectivity of ***,strong electronic metal-support interactions of Cu and the N-doped carbon support optimized the charge transfer rate,thus promoting the dissociation of water to the active hydrogen(H^(*))species and boosting the reaction kinetic rate of H^(*)and HMF.

关键词： biomass 5-hydroxymethylfurfural electrochemical reduction N-doped carbon materials 2,5-bis(hydroxymethyl)furan