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Influence of Hydrogen Bonds between Solution Molecules on the Stability of Metal Cluster in Mass Spectrometry

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Chinese Journal of Structural chemistry 2022年

Electrospray ionization time-of-flight mass spectrometry （ESI-TOF-MS） has been recognized as a powerful technique for studying metal clusters’ chemical composition and reaction mechanisms. It is a great challenge in MS analysis to maintain the metal cluster molecules intact without fragmentation, which was achieved in this work by using mixed solvents to change the interaction between cluster molecules and solvent molecules, further affecting the fragmentation behaviors of the metal cluster in MS. Theoretical analysis reveals that the stability of the [（C）Au;Ag;(C;H;ONP);];cluster in ESI-TOF-MS is related to the strength of the chemical bonds between its own atoms and the bonding between the solvent and the cluster molecules.

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Advances in microwave absorbing materials with broad-bandwidth response

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Nano Research 2023年第8期16卷 11054-11083页

作者： Susu Bao Meixi Zhang Zhiyuan Jiang Zhaoxiong Xie Lansun Zheng state key laboratory for physical chemistry of solid surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Microwave absorbing materials(MAMs)are playing an increasingly essential role in the development of wireless communications,high-power electronic devices,and advanced target detection technology.MAMs with a broad-bandwidth response are particularly important in the area of communication security,radiation prevention,electronic reliability,and military stealth.Although considerable progress has been made in the design and preparation of MAMs with a broad-bandwidth response,a number of challenges still remain,and the structure–function relationship of MAMs is still far from being completely understood.Herein,the advances in the design and research of MAMs with a broad-bandwidth response are outlined.The main strategies for expanding the effective absorption bandwidth of MAMs are comprehensively summarized considering three perspectives:the chemical combination strategy,morphological control strategy,and macrostructure control strategy.Several important results as well as design principles and absorption mechanisms are highlighted.A coherent explanation detailing the influence of the chemical composition and structure of various materials on the microwave absorption properties of MAMs is provided.The main challenges,new opportunities,and future perspectives in this promising field are also presented.

关键词： microwave absorbing materials broad-bandwidth response magnetic-dielectric synergy morphology control macrostructure control

Highly stable Eu-coordination polymer exhibiting the highest quantum yield

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Science China chemistry 2023年第5期66卷 1400-1405页

作者： Ming-Yu Ye Ming-Xuan Zhang Qiao-Fei Xu Han Xu La-Sheng Long Lan-Sun Zheng State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of chemistry College of Chemistry and Chemical EngineeringXiamenUniversityXiamen361005China

Lanthanide luminescent materials with high quantum yield and thermal stability are of key importance for their practical application.Here we report crystal structures and luminescent properties of[Eu(pfbz)_(2)(phen)Cl](1)and[Tb(pfbz)2(phen)Cl](2)(pfbz=Pentafluorobenzoate).Single-crystal analysis reveals that both 1 and 2 crystallize in a polar space group of Cmc21.Investigation on their luminescent properties indicates that the solid-state quantum yields of 1 and 2 are 97.7%and 90.7%,respectively,while their efficiency of the sensitization process is as high as 100%,revealing that polar structures are more favorable to obtain high quantum yields.Thermogravimetric analysis reveals that both 1 and 2 can be stable up to 240℃.More importantly,temperature-dependent luminescent spectra of 1 indicate its luminescent intensity at 612 nm only decreased by 5%from room temperature to 373 K,whereas at 373 K,its luminescent intensity remains almost constant for 36 h.Considering that1 represents the highest quantum yield among known Eu-coordination polymers and its performance as the LED material is better than that of commercially widely used luminescent materials of(Sr,Ca)Al Si N3:Eu(630 nm)and(Sr,Ca)Al Si N3:Eu(640 nm),the present work provides an excellent substitute for commercial LED materials.

关键词： lanthanide coordination polymers luminescence LED materials

Chemoselective and Living/Controlled Polymerization of Alkenyl Methacrylates by the Phosphonium Ylide/Organoaluminum Lewis Pairs

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Chinese Journal of Polymer Science 2024年第2期42卷 159-167,I0005页

作者： Zhi-Kang Chen Wu-Chao Zhao Yi-Ling Zhao Cong-Lei Liu Liu-Yin Jiang Yue-Tao Zhang Hong-Ping Zhu State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China state key laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun130012China

Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been realized.The P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were synthesized.In the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy groups.The pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)SH.The thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.

关键词： Phosphonium ylide Alkenyl methacrylate Chemoselectivity Living/controlled polymerization Post-functionalization

Ultrathin oxygen-containing graphdiyne wrapping CoP for enhanced electrocatalytic hydrogen generation

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Nano Research 2023年第4期16卷 5073-5079页

作者： Yan Lv Xueyan Wu Hao Li Hongbo Zhang Jiaxin Li Zhiyou Zhou Jixi Guo Dianzeng Jia state key laboratory of chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi830017China State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005China

Graphdiyne(GDY)is fascinating in the construction of efficient and stable catalysts,but their performance is still somewhat restricted due to GDY’s thicker layers,as well as hydrophobic and relatively chemically inert surfaces.Herein,via oxidationexfoliation-reduction strategy,the self-supported electrode material of CoP nanosheets with ultrathin oxygen-containing GDY wrapping(CoP@RGDYO)for effective HER is constructed.The wrapping of ultrathin oxygen-containing GDY promotes charge transfer,improves the surface property,and enhances the acid and alkali resistance as well as the structural stability of the catalyst.As a result,CoP@RGDYO shows enhanced activity and stability in both acidic and alkaline media.Especially,it exhibits a low overpotential of 86 mV and exceptional stability under a 14000-cycle cyclic voltammetry scanning in alkaline media.This work provides new ideas for the design of GDY hybrid materials and the preparation of high-efficiency catalysts.

关键词： graphdiyne chainmail catalyst hydrophilicity stability hydrogen generation

Understanding reaction mechanisms of metal-free dinitrogen activation by methyleneboranes

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Chinese Chemical Letters 2023年第2期34卷 210-213页

作者： Jie Zeng Jiaying Su Feiying You Jun Zhu State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial key laboratory of Theoretical and Computational chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Dinitrogen activation under mild conditions is important but extremely challenging due to the inert nature of the N≡N triple bond evidenced by high bond dissociation energy(945 k J/mol) and large HOMOLUMO gap(10.8 e V). In comparison with largely developed transition metal systems, the reported main group species on dinitrogen activation are rare. Here, we carry out density functional theory calculations on methyleneboranes to understand the reaction mechanisms of their dinitrogen activation. It is found that the methyleneboranes without any substituent at the boron atom performs best on dinitrogen activation, which could be contributed to its small singlet-triplet gap. In addition, strong correlations are achieved on dinitrogen activation between the singlet-triplet energy gap and the reaction energies for the formation of the end-on products as well as the side-on ones. The principal interacting orbital analysis suggests that methyleneboranes can mimic transition metals to cleave the N≡N triple bond. Our findings could be helpful for experimental chemists aiming at dinitrogen activation by main group species.

关键词： Dinitrogen activation Methyleneborane NHC-stabilized borylene Reaction mechanism Singlet–triplet gap

Synergistic coupling of amorphous carbon and graphitic domains toward high-rate and long-life K^(+) storage

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Journal of Energy chemistry 2022年第10期31卷 533-541,I0013页

作者： Hehe Zhang Wangqin Li Jianhai Pan Zhefei Sun Bensheng Xiao Weibin Ye Chengzhi Ke Haowen Gao Yong Cheng Qiaobao Zhang Ming-Sheng Wang State Key Laboratory of Physical Chemistry of Solid Surfaces College of MaterialsXiamen UniversityXiamen 361005FujianChina Fujian key laboratory of surface and Interface Engineering for High Performance Materials(Xiamen University) Xiamen 361005FujianChina

Amorphous carbon materials hold great potential for practical use in potassium-ion batteries(PIBs)due to their abundant resources,low cost and high structural stability.However,given the challenge of sluggish potassiation kinetics,the rate performance of amorphous carbon is severely hindered.Herein,amorphous carbon compounded with graphitic domains(HG-CNTs)was proposed as an advanced anode for PIBs.As directly verified by in situ transmission electron microscopy(TEM),the graphitic domains guarantee fast K-ions transport in the carbon composite at a high current density,while the amorphous carbon shells ensure the structural integrity during potassiation,thus boosting its fast and durable K^(+)storage.As a PlB anode,the HG-CNTs electrode exhibits not only a super-stable long-term cyclability(191.6 mAh g^(-1)at 1 A g^(-1)with almost no capacity decay over 3000 cycles),but also an outstanding rate performance(184.5 mAh g^(-1)at 2 A g^(-1)).Ex situ Raman and TEM results further suggest that the highly reversible structure of HG-CNTs is responsible for its superior electrochemical stability.This work provides helpful insights into the development of carbonaceous electrodes with both high rate capability and long cycle life for PIBs.

关键词： Potassium-ion batteries Amorphous carbon Graphitic domains Synergistic effect In situ TEM

Magnetoelectric effect generated through electron transfer from organic radical to metal ion

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National Science Review 2023年第4期10卷 133-141页

作者： Xiaolin Liu Qiang Liu Haixia Zhao Guilin Zhuang Yanping Ren Tao Liu Lasheng Long Lansun Zheng Collaborative Innovation Center of chemistry for Energy Materials State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University state key laboratory of Fine Chemicals Dalian University of Technology College of Chemical Engineering Zhejiang University of Technology

Magnetoelectric(ME) materials induced by electron transfer are extremely rare. Electron transfer in these materials invariably occurs between the metal ions. In contrast, ME properties induced by electron transfer from an organic radical to a metal ion have never been observed. Here, we report the ME coupling effect in a mononuclear molecule-based compound [(CH3)3NCH2CH2Br][Fe(Cl2An)2(H2O)2](1)[Cl2An = chloranilate,(CH3)3NCH2CH2Br+=(2-bromoethyl)trimethylammonium]. Investigation of the mechanism revealed that the ME coupling effect is realized through electron transfer from the Cl2An to the Fe ion. Measurement of the magnetodielectric(MD) coefficient of 1 indicated a positive MD of up to ～12% at 103.0Hz and 370 K, which is very different from that of ME materials with conventional electron transfer for which the MD is generally negative. Thus, the current work not only presents a novel ME coupling mechanism, but also opens a new route to the synthesis of ME coupling materials.

关键词： molecular ferroelectric electron transfer radical magnetoelectric effect

Nucleophilic Radicals as Hydrogen Atom Abstractors in C(sp3)-H Functionalization Reactions

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Chinese Journal of chemistry 2023年第5期41卷 544-547页

作者： Tao Li Jian Li Haohua Huo State Key Laboratory of Physical Chemistry of Solid Surfaces Key Laboratory of Chemical Biology of Fujian ProvinceCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Hydrogen atom transfer(HAT)is an elementary mechanistic step in organic synthesis.The photoredox-catalyzed HAT has transformed organic synthesis by enabling the activation and subsequent cross-coupling of traditionall... 详细信息

关键词： Radicals Hydrogen atom transfer(HAT) C(sp^(3))-H functionalization Polarity matching Photocatalysis