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Nano Research 2021年第12期14卷 4822-4827页

作者： Lijun Geng baoqi yin Hanyu Zhang Zhen-Dong Sun Zhixun Luo School of Physics Shandong UniversityJinan250100China Beijing National Laboratory for Molecular Sciences(BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of SciencesBeijing100190China School of Physics and Electrical Engineering Kashi UniversityKashgar844006China University of Chinese Academy of Sciences Beijing100049China

Due to challenges in preparing pure metal clusters and in controlling reactions,the oxides produced by metal clusters reacting with oxygen are often different from traditional ion-molecule products in the gas phase and their reactivity pattern is also largely unveiled *** this work,utilizing a customized Re-TOFMS having a home-made cluster source and a flow tube reactor,we have observed the gaseous reactions of Nin±clusters with oxygen and found magic clusters of Ni_(13)O_(8)±that dominate the mass *** quantum chemistry calculations,we find that both Ni_(13)O_(8)−and Ni_(13)O_(8)+clusters bear a regular cubic structure with 8 oxygen anchoring the eight angles,however,they have rather different spin *** Ni_(13)O_(8)−clusters have 15 unpaired spin-up electrons exhibiting cubic aromaticity and decent ferromagnetism,while the Ni_(13)O_(8)+clusters take a lower-spin ground state(11 unpaired electrons),with spin-down population on the central Ni atom pertaining to *** is a class of metalloxocube clusters that hold properties of aromaticity and ferromagnetism/ferrimagnetism charcterized by a few spin electrons,which embodies the bonding nature of superatomic compounds and enables to develop cluster-genetic materials of multi-functionality.

关键词： metalloxocube superatomic compounds aromaticity ferromagnetism cluster materials

The reactivity of O_(2) with copper cluster anions Cu_(n)^(-)(n = 7-20):Leveling effect of spin accommodation

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Chinese Chemical Letters 2022年第2期33卷 995-1000页

作者： Qiuying Du baoqi yin Si Zhou Zhixun Luo Jijun Zhao Key laboratory of Material Modiﬁcation by Laser Ion and Electron Beams(Dalian University of Technology)Ministry of EducationDalian 116024China Beijing National Laboratory for Molecular Sciences(BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

The activation of molecular oxygen is an important step in metal-catalyzed oxidation reactions and a hot subject for the research of gas-phase metal *** is known that the Ag and Au clusters readily re-act with O_(2)when they have open shell electronic *** from this,here we observed Cu_(n)^(-)(n=7−20)clusters of both open and closed shells possess high reactivity with O_(2)with few *** a combination with ab initio calculations,we demonstrate that the activation of O_(2)on the even-and odd-sized Cu_(n)^(-)clusters follows the single and double electron transfer models,*** phe-nomenon of metal clusters with different basicity to activate oxygen is enabled by the leveling effect of spin *** activity of Cu_(n)^(-)clusters is correlated to the HOMO level,and for the close-shell clusters is also governed by the vertical spin excitation energy(VSE).In encountering the attack of dioxygen,the activity of the copper cluster anions not only depends on their basicity to donate electrons,but also closely associated with the cluster *** copper clusters Cu_(n)^(-)(n=7−13)can dissociate O_(2)spontaneously,while large clusters require extra energies and display close relationship between the reaction rates and electronic vertical detachment energies(VDE).Our work illuminates a novel reaction mechanism between Cu_(n)^(-)clusters and O_(2),which sheds light in manipulating the activity and stability of coinage clusters by controlling the spin and charge states.

关键词： Copper cluster Mass spectrometry Ab initio O_(2)adsorption O_(2)dissociation Leveling effect Spin accommodation

Pure Metal Clusters with Atomic Precision for Nanomanufacturing

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Nanomanufacturing and Metrology 2022年第3期5卷 230-239页

作者： Haiming Wu Hanyu Zhang Lijun Geng Yuhan Jia Benben Huang Mengzhou Yang baoqi yin Xin Lei Zhixun Luo Beijing National Laboratory for Molecular Sciences(BNLMS)and State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Advances in cluster science have enabled the preparation of atomically precise metal clusters with one to a hundred atoms under controllable expansion *** introducing typical gas-phase cluster preparation and reaction apparatuses,this work summarized recent progress in preparing pure metal clusters of single-atom resolution,including neutral and ionic ones,with typical examples of Al,V,Nb,Fe,Co,Ni,Rh,Pt,Ag,Cu,and *** the development of soft-landing deposition technology,the size-selective pure metal clusters with strict atomic precision and predictive property will benefit nanomanufacturing down to atomic and near-atomic *** work serves as a modest motivation to stimulate the interest of scientists focusing on interdisciplinary subjects.

关键词： Metal cluster Gas phase Cluster assembly Deposition Printing

Superatomic Signature and Reactivity of Silver Clusters with Oxygen:Double Magic Ag_(17)^– with Geometric and Electronic Shell Closure

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CCS Chemistry 2021年第12期3卷 219-229页

作者： baoqi yin Qiuying Du Lijun Geng Hanyu Zhang Zhixun Luo Si Zhou Jijun Zhao State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049 Key Laboratory of Materials Modification by Laser Ion and Electron BeamsMinistry of EducationDalian University of TechnologyDalian 116024

Understanding the stability and reactivity of silver clusters toward oxygen provides insights to design new materials of coinage metals with atomic ***,we report a systematic study on anionic silver clusters,Ag_(n)^(−)(n=10-34),by reacting them with O_(2) under multiple-collision *** spectrometry observation presents the odd-even alternation effect on the reaction rates of these Agn−clusters.

关键词： metal cluster superatom gas-phase reaction Ag_(17)^– shell closure

Adsorption and activation of O2 or NO on heavy metal clusters

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Adsorption and activation of O2 or NO on heavy metal cluster...

Low-temperature adsorption of O2 on Aun-(n = 2-36)

第十五届全国化学动力学会议

作者：邢小鹏 Jun Ma baoqi yin Tingting Wang School of Chemical Science and Engineering Tongji University

We studied low-temperature adsorption and activation of O2 or NO on heavy metal clusters of Agn+/-, Aun+/-, Bin+/-, Pbn+/-etc., which contain two to tens of atoms. The reaction rates of Agn+/-and Agn+/-are closely related to their global electronic properties, while nearly independent on local structures of the adsorption sites. For Bin+/-and Pbn+/-, both the electronic properties and the local adsorption sites have significant effects. These observations imply different reaction mechanisms of these molecules on the heavy metal clusters, providing more profound views on the adsorption and activation processes on bulky metal surfaces. The reactions of O2 or NO on gold or silver clusters are also closely related to the processes on real catalysts containing dispersed gold or silver.

关键词： cluster reactions flow-reactor heavy metals adsorption of O2 adsorption NO

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Low-temperature adsorption of O2 on Aun-(n = 2-36)

Co_(12)C^(-)_(12)--metallo-carbospherenes:a new class of magic clusters for hydrogen storage

第十五届全国化学动力学会议

作者：王亭亭 Jun Ma baoqi yin Xiaopeng Xing School of Chemical Science and Engineering Tongji University

We studied low-temperature adsorption of O on Au, in which n ranges from 2 to 100. Only some even sizes can adsorb a single O molecule to form AuO, and the largest active one is found to be Au. The kinetic measurements distinguished co-existing isomers of Au, Au, and Au, while the isomers of many other sizes including the co-existing 2 D and 3 D isomers of Auhave nearly identical reaction rates. Analyses indicates that the global electronic properties of anionic gold clusters dominate the O adsorption processes, while the local structures of the adsorption sites play no or negligible effects. These observations provide more profound views on the adsorption and activation of O on real catalysts containing dispersed gold.

关键词： cluster reactions flow-reactor gold clusters adsorption of O2 isomer titration

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Science Bulletin 2022年第22期67卷 2280-2284页

作者： Lijun Geng Chaonan Cui baoqi yin Hanyu Zhang Yuhan Jia Zhixun Luo Beijing National Laboratory for Molecular Sciences(BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

Metal carbides play significant roles in electronics and materials science due to their unique properties,high strength,and high melting ***,they are applied in various organometallic synthesis and catalytic reactions,such as in the Fischer-Tropsch process and olefin metathesis[1,2],and they are able to adsorb small gas molecules such as hydrogen showing promising application for the hydrogen storage[3].Hydrogen is known as a sustainable solution for rising energy demands and an environmentally friendly option to replace fossil *** efforts have been made to develop hydrogen storage materials[4],with the aim to facilitate the application of hydrogen energy for achieving the future carbon–neutral goal set by *** has been recognized that the removal of the metal-bound terminal ligands and the doping of transition metals(TMs)on carbon substrates can improve the capacity of hydrogen adsorption[5,6].

关键词：金属碳化物光电子能谱化学惰性笼状结构超稳定极性键金属簇

Hydrogen and nitrogen absorption properties of Ce-added Zr_(2)(Fe_(1-x)Ni_(x)) alloys

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Journal of Rare Earths 2024年第6期42卷 1136-1141,I0005页

作者： Kai yin Xiaopeng Liu State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.Ltd.Beijing10088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute of Nonferrous Metals Beijing100088China

To improve the nitriding resistance of Zr_(2)Fe alloy,the Ce-added Zr_(2)(Fe_(1-x)Ni_(x))(x=0,0.15,0.3,0.5)alloys were prepared by magnetic levitation melting *** effects of Ni substitution for Fe on the phase structure,hydrogen and nitrogen absorption properties of the alloys were investigated by X-ray diffraction,scanning electron microscopy and p-c isotherm *** experimental results show that Ni substitution can effectively inhibit the formation of both α-Zr and ZrFe_(2) phases and promote the formation of C16 structure Zr_(2)(Fe,Ni)phase,causing Ni-substituted alloys to exhibit low nitrogen absorption rate and *** 623 K under 0.5 MPa nitrogen pressure,the nitrogen absorption capacity of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy reaches to 0.8 mL/g,much lower than that of Zr_(2)Fe alloy(1.5 mL/g).Ni substitution decreases the crystal cell volume of the C_(16)Zr_(2)(Fe,Ni)phase,resulting in an increase in the hydrogen absorption equilibrium *** 623 K under 0.05 MPa hydrogen pressure,the hydrogen absorption capacity decreases from 1.46 wt%of Zr_(2)Fe alloy to 1.41 wt%of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy.

关键词： Zr_(2)Fe alloy Ce Pressure-composition isotherm Hydrogen absorption Nitrogen absorption Rare earths

Rational surface charge engineering of haloalkane dehalogenase for boosting the enzymatic performance in organic solvent solutions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 276-285页

作者： yin Wu Yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Biocatalysis in organic solvents(OSs)has numerous important applications,but native enzymes in OSs often exhibit limited catalytic ***,we proposed a computation-aided surface charge engineering strategy to improve the catalytic performance of haloalkane dehalogenase DhaA in OSs based on the energetic analysis of substrate binding to the DhaA *** variants with enhanced OS resistance were obtained by replacing negative charged residues on the surface with positive charged residue(Arg).Particularly,a four-substitution variant E16R/E93R/E121R/E257R exhibited the best catalytic performance(five-fold improvement in OS resistance and seven-fold half-life increase in 40%(vol)dimethylsulfoxide).As a result,the overall catalytic performance of the variant could be at least 26 times higher than the wild-type *** spectroscopy and molecular dynamics simulation studies revealed that the residue substitution mainly enhanced OS resistance from four aspects:(a)improved the overall structural stability,(b)increased the hydrophobicity of the local microenvironment around the catalytic triad,(c)enriched the hydrophobic substrate around the enzyme molecule,and(d)lowered the contact frequency between OS molecules and the catalytic *** findings validate that computationaided surface charge engineering is an effective and ingenious rational strategy for tailoring enzyme performance in OSs.

关键词： Surface charge engineering Organic solvent resistance Molecular dynamics simulation Haloalkane dehalogenase

A generalized presentation of multi-caloric effects based on exterior derivative theory and its applications

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Communications in Theoretical Physics 2024年第8期76卷 156-163页

作者： Jun yin School of Materials Science and Engineering Nankai UniversityTianjin 300350China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China

The emerging concept of multi-caloric effects, introduced in 2010, entails the application of multiple interplay fields to a thermodynamic system. While multi-caloric effects are the main focus of experimental endeavors, theoretical considerations fall short of providing a thorough understanding. This paper introduces a comprehensive presentation on multi-caloric effects,employing the method and theory of exterior derivative formations. It addresses every aspect of thermodynamic systems, showcasing its applicability to multi-caloric materials(both singlephase and multi-phase materials), and its adaptability to different scenarios(either in single or multiple force fields). The formulation of Maxwell relationships, characterized by their generality and universality, enables a clear prediction in entropy and temperature, facilitating a distinct identification between independent and interdependent contributions from multi-caloric effects. These insights hold significant importance in designing and developing specialized thermodynamic materials, optimizing functional performances and exploring innovative mechanisms.

关键词： multicaloric effects Maxwell relations isothermal entropy adiabatic temperature