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Engineering single-atom Mn on nitrogen-doped carbon to regulate lithium-peroxide reaction kinetics for rechargeable lithium-oxygen batteries

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Journal of Energy Chemistry 2024年第7期94卷 199-207页

作者： Yaling Huang Yong Liu Yang Liu Chenyang Zhang Wenzhang Li Jie Li School of Chemistry and Chemical Engineering Central South UniversityChangsha 410083HunanChina School of Minerals Processing and Bioengineering Central South UniversityChangsha 4003HunanChina

Precision engineering of catalytic sites to guide more favorable pathways for Li_(2)O_(2) nucleation and decom-position represents an enticing kinetic strategy for mitigating overpotential,enhancing discharge capac-ity,and improving recycling stability of Li-O_(2) *** this work,we employ metal-organic frameworks(MOFs)derivation and ion substitution strategies to construct atomically dispersed Mn-N_(4) moieties on hierarchical porous nitrogen-doped carbon(Mn SAs-NC)with the aim of reducing the over-potential and improving the cycling stability of Li-O_(2) *** porous structure provides more chan-nels for mass transfer and exposes more highly active sites for electrocatalytic reactions,thus promoting the formation and decomposition of Li_(2)O_(2).The Li-O_(2) batteries with Mn SAs-NC cathode achieve lower overpotential,higher specific capacity(14290 mA h g^(-1) at 100 mAg^(-1)),and superior cycle stability(>100 cycles at 200 mA g^(-1))compared with the Mn NPs-NC and *** functional theory(DFT)cal-culations reveal that the construction of Mn-N_(4) moiety tunes the charge distribution of the pyridinic N-rich vacancy and balances the affinity of the intermediates(LiO_(2) and Li_(2)O_(2)).The initial nucleation of Li_(2)O_(2) on Mn SAs-NC favors the O_(2)-→LiO_(2)→Li_(2)O_(2) surface-adsorption pathway,which mitigates the overpoten-tials of the oxygen reduction(ORR)and oxygen evolution reaction(OER).As a result,Mn SAs-NC with Mn-N_(4) moiety effectively facilitates the Li_(2)O_(2) nucleation and enables its reversible *** work establishes a methodology for constructing carbon-based electrocatalysts with high activity and selectivity for Li-O_(2)batteries.

关键词： Single-atom Mn MOFs-oriented architecture Rechargeable Li-O_(2)battery N-doped carbon density functional theory calculation

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Regulating the intrinsic electronic structure of carbon nanofibers with high-spin state Ni for sodium storage with high-power density

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Journal of Materials Science & Technology 2024年第4期171卷 16-23页

作者： Zhijia Zhang Gang Xie Yuefang Chen Yanhao Wei Mengmeng Zhang Shulei Chou Yunxiao Wang Yifang Zhang Yong Jiang School of Materials Science and Engineering Institute of Quantum Materials and DevicesState Key Laboratory of Separation Membrane and Membrane ProcessesTiangong UniversityTianjin 300387China Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China Institute for Superconducting and Electronic Materials University of WollongongWollongongNSW 2522Australia

Carbon nanofibers(CNFs)with high specific surface area show great potential for sodium storage as a hard carbon ***,CNFs anchored with Ni nanoparticles(CNFs/Ni)were prepared through chemical vapor deposition and impregnation reduction methods,in situ growing on the three-dimensional porous copper current collector(3DP-Cu).The coupling effect of high-spin state Ni nanopar-ticles leads to the increase of defect density and the expansion of lattice spacing of ***,the 3DP-Cu ensures a high loading capacity of CNFs and short ion/electron transport *** an integral binder-free anode,the 3DP-Cu/CNFs/Ni exhibits excellent electrochemical performance,which demon-strates a high specific capacity with 298.5 mAh g^(-1)at 1000 mA g^(-1)after 1500 cycles,and a high power density with 200 mAh g^(-1)over 1000 cycles at 5000 mA g^(-1).density functional theory calculation re-sults show that the high-spin state Ni regulates the electronic structure of CNFs,which significantly reduces the adsorption energy for Na^(+)(-2.7 Ev)and thus enables high-rate *** regulation of the electronic structure of carbon materials by high-spin state metal provides a new strategy for developing high-power carbonaceous anode materials for sodium-ion batteries.

关键词： Carbon nanofibers Ni nanoparticles High-spin state Sodium-ion batteries Anode materials density functional theory calculation

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Epitaxial growth of Cu_(2-x)Se on Cu(220)crystal plane as high property anode for sodium storage

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Chinese Chemical Letters 2024年第7期35卷 519-523页

作者： Zhijia Zhang Shihao Sun Yuefang Chen Yanhao Wei Mengmeng Zhang Chunsheng Li Yan Sun Shaofei Zhang Yong Jiang School of Materials Science and Engineering Institute of Quantum Materials and DevicesState Key Laboratory of Separation Membrane and Membrane ProcessesTiangong UniversityTianjin 300387China School of Chemistry and Life Sciences Suzhou University of Science and TechnologySuzhou 215009China Key Laboratory of Advanced Electrode Materials for Novel Solar Cells for Petroleum and Chemical Industry of China Suzhou University of Science and TechnologySuzhou 215009China Hebei Key Laboratory of Flexible functional Materials/Hebei Key Laboratory of Material Near-Net Forming Technology School of Materials Science and EngineeringHebei University of Science and TechnologyShijiazhuang 050018China

Three-dimentional(3D)transition metal selenides with sufficient channels could produce significant superiority on enhancing reaction kinetics for sodium-ion ***,the thorough exploration of 3D architecture with a facile strategy is still *** we report that a polycrystalline Cu_(2-x)Se film was epitaxial grown on(220)facets-exposed Cu by direct selenization of a nanoporous Cu skeleton,which is obtained by dealloying rolled Cu Mn@Cu alloy *** functional theory calculation result shows strong adsorption energy for Se atoms on Cu(220)planes during selenization reaction,rendering a low energy *** virtue of this core-shell 3D nanoporous architecture to offer abundant active sites and endow fast electron/ion transportation,the nanoporous Cu_(2-x)Se@Cu-0.15 composite electrode exhibits remarkable sodium-ion storage properties with high reversible capacity of 950.6μAh/cm^(2)at 50μA/cm^(2),suprior rate capability of 457.6μAh/cm^(2)at 500μA/cm^(2),as well as an ultra-long stability at a high current *** investigation reveals that the electrochemical reaction is a typical conversion-type reaction with different *** novel electrode synthetic strategy provides useful instructions to design the high-performance anode material for sodium-ion batteries.

关键词： Cu_(2)se 3D architecture Anode materials density functional theory calculation Sodium-ion battery

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Mg/Fe site-specific dual-doping to boost the performance of cobalt-free nickle-rich layered oxide cathode for high-energy lithium-ion batteries

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Journal of Energy Chemistry 2024年第4期91卷 670-679页

作者： Yunting Wang Gaohui Du Di Han Wenhao Shi Jiahao Deng Huayu Li Wenqi Zhao Shukai Ding Qingmei Su Bingshe Xu Materials Institute of Atomic and Molecular Science Shaanxi University of Science and TechnologyXi'an 710021ShanxiChina Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030024ShanxiChina Key Laboratory of Interface Science and Engineering in Advanced Materials Taiyuan University of TechnologyTaiyuan 030024ShanxiChina

Layer-type LiNi0.9Mn0.1O2is promising to be the primary cathode material for lithium-ion batteries(LIBs)due to its excellent electrochemical ***,the cathode with high nickel content suffers from severely detrimental structural transformation that causes rapid capacity ***,site-specific dual-doping with Fe and Mg ions is proposed to enhance the structural stability of *** Fe3+dopants are inserted into transition metal sites(3b)and can favorably provide additional redox potential to compensate for charge and enhance the reversibility of anionic *** Mg ions are doped into the Li sites(3a)and serve as O_(2)^(-)-Mg^(2+)-O_(2)^(-)pillar to reinforce the electrostatic cohesion between the two adjacent transition-metal layers,which further suppress the cracking and the generation of harmful phase transitions,ultimately improving the *** theoretical calculations,including Bader charge and crystal orbital Hamilton populations(COHP)analyses,confirm that the doped Fe and Mg can form stable bonds with oxygen and the electrostatic repulsion of O_(2)^(-)-O_(2)^(-)can be effectively suppressed,which effectively mitigates oxygen anion loss at the high delithiation *** dual-site doping strategy offers new avenues for understanding and regulating the crystalline oxygen redox and demonstrates significant potential for designing high-performance cobalt-free nickel-rich cathodes.

关键词： Cobalt-free Layered oxide Cathode Dual dopants density functional theory calculation

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Ambient electrosynthesis of urea from carbon dioxide and nitrate over Mo_(2)C nanosheet

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Chinese Chemical Letters 2024年第8期35卷 319-323页

作者： Yue Zhang Xiaoya Fan Xun He Tingyu Yan Yongchao Yao Dongdong Zheng Jingxiang Zhao Qinghai Cai Qian Liu Luming Li Wei Chu Shengjun Sun Xuping Sun College of Chemistry and Chemical Engineering and Key Laboratory of Photonic and Electronic Bandgap MaterialsMinistry of EducationHarbin Normal UniversityHarbin 150025China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Institute for Advanced Study Chengdu UniversityChengdu 610106China College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJi’nan 250014China

Electrocatalytic synthesis of urea through C-N bond formation,converting carbon dioxide(CO_(2))and ni-trate(NO_(3)^(-)),presents a promising,less energy-intensive alternative to industrial urea production *** this communication,we report the application of Mo_(2)C nanosheets-decorated carbon sheets(Mo_(2)C/C)as a highly efficient electrocatalyst for facilitating C-N coupling in ambient urea *** CO_(2)-saturated 0.2 mol/L Na_(2)SO_(4)solution containing 0.05 mol/L NO_(3)^(-),the Mo_(2)C/C catalyst achieves an impres-sive urea yield of 579.13μg h^(-1)mg^(-1)with high Faradaic efficiency of 44.80%at-0.5 V versus the reversible hydrogen *** theoretical calculations reveal that the multiple Mo active sites enhance the formation of^(∗)CO and^(∗)NH_(2)intermediates and facilitate their C-N *** research propels the use of Mo_(2)C-based electrodes in electrocatalysis and accentuates the capabilities of binary metal-based catalysts in C-N coupling reactions.

关键词： Mo_(2)C Multiple active sites C-N coupling Electrocatalysis Urea synthesis density functional theory calculation

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Ultraviolet laser ionization studies of 1-fluoronaphthalene clusters and density functional theory calculations

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Chinese Physics B 2010年第12期19卷 223-227页

作者：张树东张海芳曾文碧 Shandong Provincial Key Laboratory of Laser Polarization and Information Technology Department of PhysicsQufu Normal University Institute of Atomic and Molecular Sciences Academia Sinica

This paper studies supersonic jet-cooled 1-fluoronaphthalene （1FN） clusters by ultraviolet （UV） laser ionization at 281 nm in a time-of-flight mass spectrometer. The （1FN）＋（n=1-3） series cluster ions are observed where the signal intensity decreases with increasing cluster size. The effects of sample inlet pressures and ionization laser fluxes to mass spectral distribution are measured. Using density functional theory calculations, it obtains a planar geometric structure of 1FN dimer which is combined through two hydrogen bonds. The mass spectra indicate that the intensity of 1FN trimer is much weaker than that of 1FN dimer and this feature is attributed to the fact that the dimer may form the first ＂shell＂ in geometric structure while the larger clusters are generated based on this fundamental unit.

关键词： 1-fluoronaphthalene clusters ultraviolet laser ionization mass spectrum density functional theory calculation

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Photocatalytic performance of TiO_2 nanocrystals with/without oxygen defects

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Chinese Journal of Catalysis 2018年第4期39卷 867-875页

作者： Shu-yuan Liu Kezhen Qi Meng Qiu Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034LiaoningChina Department of Pharmacology Shenyang Medical CollegeShenyang 110034LiaoningChina Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China College of Optoelectronic Engineering Shenzhen UniversityShenzhen 518060GuangdongChina

To investigate the role of oxygen defects on the photocatalytic activity of TiO2,the TiO2 nanocrystals with/without oxygen defects are successfully synthesized by the hydrothermal and sol‐gel methods,*** as‐prepared TiO2 nanocrystals with defects are light blue and the absorption edge of light is towards the visible light region(~420 nm).Raman and X‐ray photoelectron spectroscopy(XPS)measurements all confirm that the concentration of oxygen vacancies in the TiO2 synthesized by the sol‐gel method is less than that synthesized through the hydrothermal *** introduction of oxygen defects contributes to a new state in the band gap that narrows the band gap,which is the reason for the extension of light absorption into the visible light *** photocurrent results confirm that this band‐gap narrowing enhances the photocurrent response under simulated solar light *** TiO2 with oxygen defects shows a higher photocatalytic activity for decomposition of a methylene blue solution compared with that of the perfect TiO2 *** photocatalytic mechanism is discussed based on the density functional theory calculations and photoluminescence spectroscopy measurements.

关键词： TiO2 Defect Optical property Photocatalytic activity density functional theory calculation

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Catalytic roles of the acid sites in different pore channels of H‐ZSM‐5 zeolite for methanol‐to‐olefins conversion

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Chinese Journal of Catalysis 2021年第7期42卷 1126-1136页

作者： Sen Wang Zhikai Li Zhangfeng Qin Mei Dong Junfen Li Weibin Fan Jianguo Wang State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina University of the Chinese Academy of Sciences Beijing 100049China

H‐ZSM‐5 zeolite is a typical catalyst for methanol‐to‐olefins(MTO)*** the performance of zeolite catalysts for MTO conversion is related to the actual location of acid sites in the zeolite framework,the catalytic roles of the acid sites in different pore channels of the H‐ZSM‐5 zeolite are not well *** this study,the MTO reaction network,involving the aromatic cycle,alkene cycle,and aromatization process,and also the diffusion behavior of methanol feedstock and olefin and aromatic products at different acid sites in the straight channel,sinusoidal channel,and intersection cavity of H‐ZSM‐5 zeolite was comparatively investigated using density functional theory calculations and molecular dynamic *** results indicated that the aromatic cycle and aromatization process occurred preferentially at the acid sites in the intersection cavities with a much lower energy barrier than that at the acid sites in the straight and sinusoidal *** contrast,the formation of polymethylbenzenes was significantly suppressed at the acid sites in the sinusoidal and straight channels,whereas the alkene cycle can occur at all three types of acid sites with similar energy barriers and ***,the catalytic performance of H‐ZSM‐5 zeolite for MTO conversion,including activity and product selectivity,can be regulated properly through the purposive alteration of the acid site distribution,viz.,the location of Al in the zeolite *** study helps to elucidate the relation between the catalytic performance of different acid sites in the H‐ZSM‐5 zeolite framework for MTO conversion,which should greatly benefit the design of efficient catalyst for methanol conversion.

关键词： Methanol‐to‐olefins H‐ZSM‐5 zeolite Acid site distribution density functional theory calculation Molecular dynamic simulation

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Iron phthalocyanine-catalyzed radical phosphinoylazidation of alkenes:A facile synthesis of β-azido-phosphine oxide with a fast azido transfer step

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Chinese Journal of Catalysis 2021年第10期42卷 1634-1640页

作者： Xiaoxu Ma Mong-Feng Chiou Liang Ge Xiaoyan Li Yajun Li Li Wu Hongli Bao Key Laboratory of Coal to Ethylene Glycol and Its Related Technology State Key Laboratory of Structural ChemistryCenter for Excellence in Molecular SynthesisFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002FujianChina School of Chemistry and Environmental Engineering Wuhan Institute of TechnologyWuhan 430205HubeiChina University of Chinese Academy of Sciences Beijing 100049China

Phosphinoylazidation of alkenes is a direct method to build nitrogen-and phosphorus-containing compounds from feed-stock *** the advances in other phosphinyl radical related difunctionalization of alkenes,catalytic phosphinoylazidation of alkenes has not yet been ***,we describe the first iron-catalyzed intermolecular phosphinoylazidation of styrenes and unactivated *** method is practically useful and requires a relatively low loading of *** studies confirmed the radical nature of the reaction and disclosed the unusually low activation energy 4.8 kcal/mol of radical azido group transfer from the azidyl iron(III)phthalocyanine species(PcFeulN3)to a benzylic *** work may help to clarify the mechanism of iron-catalyzed azidation,inspire other mechanism studies and spur further synthetic applications.

关键词： Iron phthalocyanine Phosphinoylazidation Difunctionalization Radical group transfer density functional theory calculation

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Investigation on Non-covalent Complexes of Cyclodextrins with Li＋ in Gas Phase by Mass Spectrometry

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Chinese Journal of Chemical Physics 2013年第3期26卷 287-294,I0003页

作者：何小丹魏王慧储艳秋刘智攀丁传凡复旦大学化学系激光化学研究所上海200433 复旦大学化学系物理化学研究所上海200433

To investigate the non-covalent interaction between cyclodextrins （CD） and lithium ion, a stoichiometry of α-CD, β-CD, heptakis（2,6-di-O-methyl）-β-CD （DM-β-CD）, or heptakis（2,3,6-tri-O-methyl）-β-CD （TM-β-CD） was mixed with lithium salt, respectively, and then incubated at room temperature for 10 min to reach the equilibrium. In posi- tive mode, the electrospray ionization mass spectrometry （ESI-MS） results demonstrated that lithium ion can conjugate to α-, β-, DM-β- or TM-β-CD and form 1：1 stoichiometric non-covalent complexes. The binding of the complexes was further confirmed by collision- induced dissociation. The dissociation constants Kdl of four complexes （Li＋α-CD, Li＋β- CD, Li＋DM-β-CD, and Li＋TM-β-CD） were determined by mass spectrometric titration. The results showed Kdl were 18.7, 26.7, 33.6, 30.5 μmol/L for the complexes of Li＋ with α-CD, β-CD, DM-β-CD, and TM-β-CD, respectively. Kdl for the Li＋ complexes of/3-CD is smaller than that of DM-β-CD due to its steric effect of the partial substituted -CH3. The Kdl for the Li＋ complexes of DM-β-CD is nearly in agreement with that of TM-β-CD, indicating Li＋ is more likely to locate in the small rim of DM-β-CD＇s hydrophobic cavity. The DFT results showed through electrostatic interaction, one Li＋ can strongly conjugate to four neighboring oxygen atoms. For the （α-CD＋Li）＋ complex, one Li＋ may also situate the small rim of α-CD＇s hydrophobic cavity to form a non-specific host-guest complex.

关键词： Non-covalent complex Lithium ion Cyclodextrin Dissociation constant Massspectrometry density functional theory calculation

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