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Applications of in-situ solid-state nuclear magnetic resonance (ssNMR) in methanol to olefins (MTO) reaction

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Science China Chemistry 2024年

作者： Jing Niu Shutao Xu Yingxu Wei Zhongmin Liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of Sciences State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences University of Chinese Academy of sciences

The methanol-to-olefins (MTO) reaction offers an alternative pathway for the production of low-carbon olefins from non-oil *** research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in ***-situ solid-state nuclear magnetic resonance (ssNMR) spectroscopy has emerged as a pivotal tool,offering crucial insights into key species under real-time operando ***,the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ13C MAS NMR and 2D correlation ***,recent technological advancements in hyperpolarization (HP) methods,including HP129Xe NMR and dynamic nuclear polarization (DNP),have significantly improved the sensitivity of ssNMR,enabling detailed structural and kinetic analysis as well as the detection of trace *** this feature article,we summarized recent advancements in (in-situ) ssNMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest *** theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts,thereby advancing the techniques towards more sustainable and economical production route for olefins.

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Ultrathin ternary PtNiGa nanowires for enhanced oxygen reduction reaction

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Chinese chemical Letters 2024年第2期35卷 599-603页

作者： Giday Fisseha Yiping Hu Yanan Yu Shaojie Lu Dongsheng Ma Pei Nian Zheng Wang Qin Yue Institute of Fundamental and Frontier sciences University of Electronic Science and Technology of ChinaChengdu 610054China State Key Laboratory of High-efficiency Utilization of Coal and Green chemical Engineering School of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021China

Achieving high activity and durability for the oxygen reduction reaction(ORR)with an ultra-low amount of platinum is significant to promote the widespread application of proton exchange membrane fuel cells(PEMFCs).Here we report a new ultrathin(∼1 nm)ternary PtNiGa alloy nanowires(PtNiGa NWs)electrocatalyst,in which the presence of gallium(Ga)enhances the oxidation resistance of platinum(Pt)and nickel(Ni)and suppresses the dissolution of *** mass and specific activities of PtNiGa NWs are about 11.2 and 7.6 times higher than those of commercial Pt/C catalysts for ***,the mass activity of PtNiGa/C NWs nanocatalyst decreased only by 12.8%and largely retained its electrochemical surface area(ECSA)after 10,000 potential cycles,compared with 38%loss of ECSA for commercial Pt/C ***,this work provides a general guideline for preparing ternary alloy electrocatalysts and enhancing the activity and stability of the cathode ORR reaction of PEMFCs.

关键词： Ultrathin nanowires Gallium Oxygen reduction reaction Ternary alloy Durability

High-performance and robust high-temperature polymer electrolyte membranes with moderate microphase separation by implementation of terphenyl-based polymers

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Journal of Energy Chemistry 2024年第5期92卷 572-578页

作者： Jinyuan Li Congrong Yang Haojiang Lin Jicai Huang Suli Wang Gongquan Sun Division of Fuel Cells and Battery Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Key Laboratory of Fuel Cells&Hybrid Power Sources Chinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of sciences Beijing 100039China

Acid loss and plasticization of phosphoric acid(PA)-doped high-temperature polymer electrolyte membranes(HT-PEMs)are critical limitations to their practical application in fuel *** overcome these barriers,poly(terphenyl piperidinium)s constructed from the m-and p-isomers of terphenyl were synthesized to regulate the microstructure of the *** rigid p-terphenyl units prompt the formation of moderate PA aggregates,where the ion-pair interaction between piperidinium and biphosphate is reinforced,leading to a reduction in the plasticizing *** a result,there are trade-offs between the proton conductivity,mechanical strength,and PA retention of the membranes with varied m/p-isomer *** designed PA-doped PTP-20m membrane exhibits superior ionic conductivity,good mechanical strength,and excellent PA retention over a wide range of temperature(80–160°C)as well as satisfactory resistance to harsh accelerated aging *** a result,the membrane presents a desirable combination of performance(1.462 W cm^(-2) under the H_(2)/O_(2)condition,which is 1.5 times higher than that of PBI-based membrane)and durability(300 h at 160°C and 0.2 A cm^(-2))in the fuel *** results of this study provide new insights that will guide molecular design from the perspective of microstructure to improve the performance and robustness of HT-PEMs.

关键词： Fuel cell High-temperature polymer electrolyte membranes Microphase separation Poly(terphenyl piperidinium)s Phosphoric acid

In-situ synthesis of quantum dots in the nucleus of live cells

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National Science Review 2024年第3期11卷 172-182页

作者： Yusi Hu Zhi-Gang Wang Haohao Fu Chuanzheng Zhou Wensheng Cai Xueguang Shao Shu-Lin Liu Dai-Wen Pang State Key Laboratory of Medicinal chemical Biology Frontiers Science Centre for New Organic MatterTianjin Key Laboratory of Biosensing and Molecular Recognition Research Centre for Analytical Sciences College of Chemistry School of Medicine and Frontiers Science Centre for Cell Responses Nankai University Haihe Laboratory of Sustainable chemical Transformations

The cell nucleus is the main site for the storage and replication of genetic material, and the synthesis of substances in the nucleus is rhythmic, regular and strictly regulated by physiological processes. However,whether exogenous substances, such as nanoparticles, can be synthesized in situ in the nucleus of live cells has not been reported. Here, we have achieved in-situ synthesis of CdSxSe1-xquantum dots（QDs） in the nucleus by regulation of the glutathione（GSH） metabolic pathway. High enrichment of GSH in the nucleus can be accomplished by the addition of GSH with the help of the Bcl-2 protein. Then, high-valence Se is reduced to low-valence Se by glutathione-reductase-catalyzed GSH, and interacts with the Cd precursor formed through Cd and thiol-rich proteins, eventually generating QDs in the nucleus. Our work contributes to a new understanding of the syntheses of substances in the cell nucleus and will pave the way for the development of advanced ‘supercells’.

关键词： glutathione live cell nucleus quantum dot intracellular synthesis

NaBH4-induced phase transition of CoSe_(2) with abundant Se deficiency for acidic oxygen reduction to hydrogen peroxide

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Rare Metals 2024年第2期43卷 500-510页

作者： Cai-Di Han Yong-Chao Zhang Qian Zhang Jin-Ting Wu Jian Gao Ji-Jun Zou Xiao-Dong Zhu State Key Laboratory Base of Eco-chemical Engineering College of chemical Engineering Qingdao University of Science and TechnologyQingdao266042China Key Laboratory for Green chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China

Electrocatalytic oxygen reduction(ORR)via the 2e−pathway to form H_(2)O_(2) in acidic medium has attracted extensive ***,the low activity,insufficient selectivity and high cost of catalysts have been the ***,CoSe_(2) with abundant Se deficiency was synthesized by a simple hydrothermal method,and the addition of NaBH4-induced CoSe_(2) phase transition from orthorhombic to cubic phase with more Se *** cubic phase CoSe_(2) with abundant Se deficiency can effectively regulate the surface electronic structure with suitable binding energies of*OOH and*O,which shows high activity,selectivity and long-term stability for acidic ORR to H_(2)O_(2).The onset potential is as low as 0.73 V *** hydrogen electrode(RHE),the H_(2)O_(2) selectivity is 84%(0 V ***),and the average electron transfer number is about ***,the H_(2)O_(2) yield measured using a flow cell is as high as 115.92 mmol·gcat.^(−1)·h^(−1) and the Faradaic efficiency is 70%at 0 V ***,which presents high potential in electrocatalytic acidic ORR to H_(2)O_(2) and organic pollutant degradation using the electron-Fenton process.

关键词： Se defected CoSe_(2) Crystal phase transition Electrocatalysis Acidic oxygen reduction Hydrogen peroxide

Copper-Free Click Chemistry-Mediated Assembly of Single Quantum Dot Nanosensor for Accurately Monitoring Locus-Specific m^(6)A in Cancer Cells

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Chinese Journal of Chemistry 2024年第5期42卷 499-504页

作者： Yue-Ying Li Ning-Ning Zhao Yi-Xuan Geng Qian Han Jian-Ge Qiu Bing-Hua Jiang Zi-Yue Wang Chun-Yang Zhang Translational Medicine Center The First Affiliated Hospital of Zhengzhou UniversityThe Academy of Medical SciencesHenan Institute of Medical and Pharmaceutical Sciences BGI CollegeZhengzhou UniversityZhengzhouHenan450052 China College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJinanShandong250014 China School of Chemistry and chemical Engineering Southeast UniversityNanjingJiangsu211189 China

N6-methyladenosine(m^(6)A)plays an important role in embryogenesis,nuclear export,transcription splicing,and protein translation ***,we demonstrate a copper-free click chemistry-mediated assembly of single quantum dot(QD)nanosensor for accurately monitoring locus-specific m^(6)A in cancer *** m^(6)A-sensitive endoribonuclease MazF can digest the unmethylated A-RNA,and the intact m^(6)A-RNA then hybridizes with DNA probes a and b to produce a sandwich hybrid,initiating the click chemistry to generate probe a–b ligation product via first tandem ligation detection reaction(LDR)***,DNA probes c and d can hybridize with the probe a–b ligation product to generate the probe c–d ligation product via second LDR *** LDR cycles can be repeated through denaturation and annealing reaction to generate abundant biotin-/fluorophore-modified probe c–d ligation products that can easily assemble on the QD surface to induce distinct fluorescence resonance energy transfer(FRET)between QD and *** assay can be homogenously performed without the involvement of copper catalyst,m^(6)A-specific antibody,radioactive labeling,ligase enzyme,enzymatic reverse transcription,and next-generation ***,it can discriminate even 0.01% m^(6)A level in complex samples and accurately measure cellular m^(6)A-RNA expression,providing a promising avenue for clinical diagnostics and biomedical research.

关键词： RNA methylation Click chemistry Förster resonance energy transfer Biosensor Cancer

Multistep Desolvation as a Fundamental Principle Governing Peptide Self-Assembly Through Liquid-Liquid Phase Separation

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CCS Chemistry 2024年第1期6卷 255-265页

作者： Chengqian Yuan Ruirui Xing Jie Cui Wei Fan Junbai Li Xuehai Yan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190 School of chemical Engineering University of Chinese Academy of SciencesBeijing 100049 Analysis and Test Center Institute of ChemistryChinese Academy of SciencesBeijing 100190 Beijing National Laboratory for Molecular sciences CAS Key Laboratory of ColloidInterface and Chemical ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijing 100190 Center for Mesoscience Institute of Process EngineeringChinese Academy of SciencesBeijing 100190

Biomolecular self-assembly based on peptides and proteins is a general phenomenon encountered in natural and synthetic ***–liquid phase separation(LLPS)is intimately involved in biomolecular self-assembly,yet the key factors at a molecular scale activating or modulating such a process remain largely ***,we discovered in our experiments that multistep desolvation is fundamental to the formation and evolution of peptide-rich droplets:The first step was partial desolvation of peptides to form peptide clusters,and the second step was selective desolvation of hydrophobic groups within clusters to trigger LLPS and the formation of peptiderich droplets,followed by complete desolvation of droplets,initiating the nucleation of peptide *** of the degree of desolvation at different stages was an effective strategy to control the self-assembly pathways and *** study sheds light on the molecular origin of LLPS-mediated self-assembly distinct from classical one-step self-assembly and paves the way for the precise control of supramolecular self-assembly.

关键词： peptide liquid-liquid phase separation multistep desolvation nanostructures self-assembly

Pd-catalyzed asymmetric carbonyl alkynylation:Synthesis of axial chiral ynones

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Chinese chemical Letters 2024年第6期35卷 293-297页

作者： Long Jin Jian Han Dongmei Fang Min Wang Jian Liao Natural Products Research Center Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China College of chemical Engineering Sichuan UniversityChengdu 610065China University of Chinese Academy of sciences Beijing 100049China

Ynones are important skeletons in bioactive molecules and valuable building blocks for organic synthesis,thus great efforts have been devoted to their ***,introducing prochiral substrates to construct ynones bearing a chiral framework is unrealized to ***,we reported the first example of Pd/SOP-catalyzed asymmetric carbonylative alkynylation via a non-classical carbonylative Sonogashiratype approach(acyl-Pd(Ⅱ)species generated from nucleophiles).By using cyclic diaryliodonium salts as prochiral substrates,various axial chiral ynones with good functional group tolerance(39 examples),satisfied yields(71%-96%)and excellent enantioselectivities(generally 94%-99%ee)were *** of bioactive compounds,scale-up experiment and useful transformations were also conducted to demonstrate the utility of this process.

关键词： Pd-catalyzed Axial chiral ynones Cyclic diaryliodonium High-valent palladium catalyzed Asymmetric carbonyl alkynylation

Regulating the non-effective carriers transport for high-performance lithium metal batteries

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Journal of Energy Chemistry 2024年第5期92卷 132-141页

作者： Simeng Wang Youchun Yu Shaotong Fu Hongtao Li Jiajia Huang Institute of Process Engineering Chinese Academy of SciencesBeijing 100190China School of chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Haike Group Research Institute of Innovation&Technology Dongying 257000ShangdongChina

The absence of control over carriers transport during electrochemical cycling,accompanied by the deterioration of the solid electrolyte interphase(SEI)and the growth of lithium dendrites,has hindered the development of lithium metal ***,a separator complexion consisting of polyacrylonitrile(PAN)nanofiber and MIL-101(Cr)particles prepared by electrospinning is proposed to bind the anions from the electrolyte utilizing abundant effective open metal sites in the MIL-101(Cr)particles to modulate the transport of non-effective *** binding effect of the PANM separator promotes uniform lithium metal deposition and enhances the stability of the SEI layer and long cycling stability of ultra-high nickel layered oxide *** PANM as the Li||NCM96 separator enables high-voltage cycling stability,maintaining 72%capacity retention after 800 cycles at a charging and discharging rate of 0.2 C at a cut-off voltage of 4.5 V and 0°***,the excellent high-rate performance delivers a specific capacity of 156.3 mA h g^(-1) at 10 *** addition,outstanding cycling performance is realized from−20 to 60°*** separator engineering facilitates the electrochemical performance of lithium metal batteries and enlightens a facile and promising strategy to develop fast charge/discharge over a wide range of temperatures.

关键词： Functional separators Metal-organic frameworks 3D continuous ion transport networks Electrospinning Lithium metal batteries