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Nano Research 2024年第7期17卷 5914-5921页

作者： Chun-Ying Chen Qi-Jie Mo Fu-Zhen Li Hai-Li Song Li Zhang MOE Laboratory of Bioinorganic and Synthetic chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon ***,we reported the precise immobilization of metal single atoms(M-SAs;M=Ru,Rh,Ir,Pd,Pt,and Au)into a porphyrinic metalorganic framework(MOF)of PCN-222(PCN=porous coordination network),and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene *** solvent-free conditions,Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room *** and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates,which helped to condense the substrates in the cavities of the porous *** density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway.

关键词： alkene hydrosilylation single atom catalysts metal-organic frameworks precision chemistry synergistic catalysis

Mass transfer in heap leaching of weathered crust elution deposited rare earth ore with Al_(2)(SO_(4))_(3) solution

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Journal of Rare Earths 2024年第6期42卷 1175-1181,I0007页

作者： Jingqun Yin Dedong Zeng Jun Tian Yaqing Weng institute of Applied chemistry Jiangxi Academy of SciencesNanchang330096China School of chemistry and Chemical Engineering Nanchang UniversityNanchang330031China

In order to increase efficiency and avoid NH^(4+)-N pollution in the leaching process of weathered crust elution-deposited rare earth ores,the mass transfer in heap leaching with Al_(2)(SO_(4))_(3) solution was simulated with column elution and experimentally *** results indicate that the leaching yield is also up to 99%for leaching with aluminum sulfate instead of ammonium *** optimal flow rate is 60 mL/h,the height equivalent to a theoretical plate(HETP)is 1.29 mm *** peak value position of RE^(3+)is 60 mL/h,Fe^(3+)is 100 mL/h,however,Al^(3+)is 150 mL/h,and the heap leaching process has kinetic separation effect.

关键词： Raree arths Mass transfer Process optimization Heapleaching Weathered crust elution-deposited rare earth ore

Covalent triazine frameworks modified by ultrafine Pt nanoparticles for efficient photocatalytic hydrogen production

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Nano Research 2024年第6期17卷 4908-4915页

作者： Xu Han Xueying Ge Wen-Wen He Wangwang Shen Tao Zhou Jian-Sen Wang Rong-Lin Zhong Abdullah MAl-Enizi Ayman Nafady Shengqian Ma School of chemistry and Life Science Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012China Laboratory of Theoretical and Computational chemistry Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China Department of chemistry University of North Texas1508 W.Mulberry St.DentonTX 76201USA Department of chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

Pt nanoparticles(PtNPs)as active species have always been considered as one of the best semiconductor materials for photocatalytic hydrogen *** this study,a Schottky heterojunction has been successfully constructed by evenly loading ultrafine PtNPs onto a triazine-based covalent organic frameworks(COFs).This strategy maintained the high activity of these ultra-small PtNPs while maximizing the utilization of the Pt active *** fabricated PtNPs@covalent triazine-based framework-1(CTF-1)composite accomplished a significantly high rate of hydrogen evolution(20.0 mmol·g^(−1)·h^(−1),apparent quantum efficiency(AQE)=7.6%,atλ=450 nm)with 0.40 wt.%Pt loading,giving rise to a 44-fold-increase in the efficiency of the photocatalytic hydrogen production compared to the pristine *** calculations revealed that the strong electron transfer(Q(Pt)=−0.726 qe,in the analysis of Bader charge,Q(Pt)is the charge quantity transferred from Pt cluster to CTF-1,and qe is the unit of charge transfer quantity)between PtNPs and CTF-1 triggers a strong interaction,which makes PtNPs being firmly attached to the structure of CTF-1,thereby enabling high stability and excellent hydrogen production ***,the hydrogen binding free energy(ΔGH*)of PtNPs@CTF-1 is much lower than that of the unmodified CTF-1,leading to a much lower intermediate state and hence a significant improvement in photocatalytic *** overall findings of this work provide a new platform to incorporate metallic NPs into COFs for the design and fabrication of highly efficient photocatalysts.

关键词： Pt nanoparticles covalent triazine-based framework-1(CTF-1) photocatalysts hydrogen evolution reaction

Stabilization and detection of labile reaction intermediates in supramolecular containers

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Chinese Chemical Letters 2024年第6期35卷 47-52页

作者： Rui Wang Yang Liang Julius Rebek Jr. Yang Yu Center for Supramolecular chemistry&Catalysis and Department of chemistry College of ScienceShanghai UniversityShanghai 200444China Skaggs institute for Chemical Biology and Department of chemistry The Scripps Research InstituteLa JollaCA 92037United States

Detection and observation of reactive intermediates is an essential step in investigation of reaction ***,most reactive intermediates are unstable and present at low concentrations;their short lifetimes make them difficult to detect and *** containers offer opportunities for the stabilization and characterization of those labile species,through isolation from the media and protection inside the cavity of the *** this review,we summarize the examples of labile reaction intermediates that are stabilized and characterized with the help of supramolecular *** container compounds include carcerands,deep cavitands and amide *** focus on unstable guest species-cyclobutadiene,benzocyclopropenone,o-benzyne,1,2,4,6-cycloheptatetraene,anti-Bredt's olefin,fluorophenoxycarbene,O-acylisoamide,and hemiaminalthat act as intermediates in certain organic reactions.

关键词： Supramolecular containers Reaction intermediates Labile species stabilization Short-lived species detection Supramolecular chemistry

Photocatalyzed ditrifluoromethylthiolation of alkenes with CF_(3)SO_(2)Na

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Science China chemistry 2024年第2期67卷 587-594页

作者： Fangming Chen Lvqi Jiang Chunyang Hu Jie Liu Wenbin Yi School of chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China Key Laboratory of Organofluorine chemistry Shanghai Institute Organic ChemistryChinese Academy of SciencesShanghai200032China

Since the first report of sodium trifluoromethanesulfinate(CF_(3)SO_(2)Na) as an electrophilic trifluoromethylthiolation reagent in 2015,there has been no breakthrough in research in this ***,we disclose an unprecedented usage of CF_(3)SO_(2)Na as a radical trifluoromethylthiolation reagent.A photocatalyzed ditrifluoromethylthiolation of alkenes with CF_(3)SO_(2)Na in the presence of PPh_(3) and catalytic copper has been ***,either Ir[(p-Fppy)_(2)(bpy)]PF_6 or Ir(ppy)_(3) could facilitate this *** studies indicate that initiation of the radical chain proceeded via two different photocatalytic quenching *** protocol provides a practical method for the construction of diverse vicinal ditrifluoromethylthiolated compounds.

关键词： trifluoromethylthiolation photocatalysis radical difunctionalization alkenes

Si/TiO2 carbon fiber core encapsulated in hierarchical multiple MXene@Co-MoS2 shells for constructing a free-standing anode of lithium storage

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Rare Metals 2024年第9期43卷 4222-4233页

作者： Xian-ping Du Ying Huang Jia-ming Wang Zhen-he Feng Xu Sun MOE Key Laboratory of Material Physics and chemistry Under Extraordinary Conditions School of Chemistry and Chemical Engineering Northwestern Polytechnical University Shanghai institute of Space Power-Sources Ningbo institute of Northwestern Polytechnical University

Silicon-based（Si-based） materials offer more possibilities for generating new portable electronic devices due to their high specific capacities. However, their inferior electrical conductivity and volume expansion during cycling seriously limit their development. The optimum solution is to select specific materials to establish an exceptionally conductive and volume buffer structure,which can assist Si materials in developing their excellent lithium storage properties. In this study, Si particles were confined in TiO2carbon fibers（TiO2CFs） via electrospinning, after which they were encapsulated with MXene and Co-MoS2（CMS） nanosheets to fabricate hierarchical ST-2@MXene@CMS films. TiO2CF, MXene and CMS were employed to establish a coherent conductive network with one-, two-and three-dimensional electronic pathways to permit the unimpeded flow of electrons inside the electrode material. TiO2CF, MXene and CMS acted precisely as multilayered buffers to ameliorate the volume change of Si particles during cycling. In addition, the CMS nanosheets were involved in lithium storage, contributing to the final electrochemical performance. Ultimately, the ST-2@MXene@CMS films served as free-standing electrodes, avoiding the impact of inactive interfaces on the electrochemical performance and fulfilling the lightweight requirement for new energy storage devices.

关键词： Co-MoS2 nanosheets Hierarchical structure Lithium-ion batteries MXene Si particles

Combining cisplatin and a STING agonist into one molecule for metalloimmunotherapy of cancer

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National Science Review 2024年第1期11卷 107-119页

作者： Shuren Zhang Dongfan Song Wenhao Yu Ji Li Xiaoyu Wang Yachao Li Zihan Zhao Qi Xue Jing Zhao Jie P.Li Zijian Guo State Key Laboratory of Coordination chemistry School of Chemistry and Chemical EngineeringChemistry and Biomedicine Innovation Center (ChemBIC) Nanjing University Department of Urology Afflliated Drum Tower HospitalMedical SchoolNanjing University Nanchuang (Jiangsu)institute of chemistry and Health

Mounting evidence suggests that strategies combining DNA-damaging agents and stimulator of interferon genes(STING) agonists are promising cancer therapeutic regimens because they can amplify STING activation and remodel the immunosuppressive tumor microenvironment. However, a single molecular entity comprising both agents has not yet been developed. Herein, we designed two PtIV-MSA-2 conjugates(Ⅰand Ⅱ) containing the DNA-damaging chemotherapeutic drug cisplatin and the innate immuneactivating STING agonist MSA-2; these conjugates showed great potential as multispecific small-molecule drugs against pancreatic cancer. Mechanistic studies revealed that conjugate Ⅰ upregulated the expression of transcripts associated with innate immunity and metabolism in cancer cells, significantly differing from cisplatin and MSA-2. An analysis of the tumor microenvironment demonstrated that conjugate I could enhance the infiltration of natural killer(NK) cells into tumors and promote the activation of T cells, NK cells and dendritic cells in tumor tissues. These findings indicated that conjugate I, which was created by incorporating a Pt chemotherapeutic drug and STING agonist into one molecule, is a promising and potent anticancer drug candidate, opening new avenues for small-molecule-based cancer metalloimmunotherapy.

关键词： platinum drug STING agonist single-molecule multitarget metalloimmunology

Dielectric Constant Calculation of Poly(vinylidene fluoride)Based on Finite Field and Density Functional Theory

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Chinese Journal of Polymer Science 2024年第5期42卷 655-662,I0009页

作者： Yong-Zhi Lin Lu-Kun Feng Ya-Dong Li Chao-Fan Chang Cai-Zhen Zhu Ming-Liang Wang Jian Xu College of chemistry and Environmental Engineering Shenzhen UniversityShenzhen518055China Chengdu institute of Organic chemistry Chinese Academy of SciencesChengdu610041China

In this study,we proposed a novel method that integrates density functional theory(DFT)with the finite field method to accurately estimate the polarizability and dielectric constant of *** approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric *** validated our method using polyethylene(PE)and polytetrafluoroethylene(PTFE)as benchmark materials,and found that it reliably predicted their dielectric ***,we explored the impact of conformation variations in poly(vinylidene fluoride)(PVDF)on its dielectric constant and *** resulting dielectric constants ofα-andγ-PVDF(3.0)showed excellent agreement with crystalline PVDF in *** findings illuminate the relationship between PVDF’s structural properties and its electrical behavior,offering valuable insights for material design and applications.

关键词： Dielectric constant PVDF Finite field DFT

Diatomic Fe-Co catalysts synergistically catalyze oxygen evolution reaction

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Nano Research 2024年第5期17卷 3794-3800页

作者： Tianmi Tang Jingyi Han Zhenlu Wang Xiaodi Niu Jingqi Guan institute of Physical chemistry College of ChemistryJilin UniversityChangchun 130021China College of Food Science and Engineering Jilin UniversityChangchun 130062China

The design of diatomic catalysts with uniformly dispersed metal atoms is expected to improve catalytic performance,which is conducive to the intensive comprehending of the synergistic mechanism between dual-metal sites for the oxygen evolution reaction(OER)at the atomic ***,we design a strategy to immobilize bimetallic Fe-Co atoms onto nitrogen-doped graphene to obtain a diatomic catalyst(DA-FC-NG)with FeN_(3)-CoN_(3) *** DA-FC-NG shows excellent OER activity with a low overpotential(η_(10)=268 mV),which is superior to commercial iridium dioxide *** calculations uncover that the excellent activity of DA-FC-NG is due to the interaction between Fe and Co diatoms,which causes charge rearrangement and induces the adsorption of intermediates on the Fe-O-Co bridge structure,thus improving the catalytic OER *** work is of great significance for the design of highly active diatomic catalysts to replace noble metal catalysts for energy-related applications.

关键词： oxygen evolution reaction diatomic catalyst FeN_(3)-CoN_(3) X-ray absorption spectroscopy(XAS)spectrum theoretical calculation

Making topological protein links using enzymatic reactions

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National Science Review 2024年第03期11卷 50-51页

作者： Roger Castells-Graells Todd O.Yeates Department of chemistry and Biochemistry University of California UCLA-DOE institute for Genomics and Proteomics

Proteins are exceedingly complex molecules though, at their heart, they are essentially linear polymers. Pull at their ends and one obtains an extended backbone. While that is true in most cases, some natural proteins... 详细信息

关键词： DESIGN