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High-energy-density lithium manganese iron phosphate for lithium-ion batteries: Progresses, challenges, and prospects

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Journal of Energy Chemistry 2025年第01期 1-17页

作者： Bokun Zhang Xiaoyun Wang Shuai Wang Yan Li Libo Chen Handong Jiao Zhijing Yu Jiguo Tu State Key Laboratory of advanced Metallurgy University of Science and Technology Beijing Research institute for Intelligent Wearable Systems The Hong Kong Polytechnic University institute of advanced Structure Technology Beijing Institute of Technology

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate (LiMnxFe1-xPO4) has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** LiMnxFe1-xPO4has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMnxFe1-xPO4to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMnxFe1-xPO4,including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable LiMnxFe1-xPO4materials,to achieve practical energy storage requirements.

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Effect of milling atmosphere on structural and magnetic properties of Ni-Zn ferrite nanocrystalline

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Chinese Physics B 2015年第4期24卷 481-490页

作者： Abdollah Hajalilou Mansor Hashim Reza Ebrahimi-Kahrizsangi Mohamad Taghi Masoudi Material synthesis and Characterization Laboratory Institute of Advanced Technology (ITMA)Universiti Putra Malaysia advanced Materials Research Center Materials Engineering Department Najafabad Branch Islamic Azad University

Powder mixtures of Zn, NiO, and Fe2O3 are mechanically alloyed by high energy ball milling to produce Ni-Zn ferrite with a nominal composition of Ni0.36Zn0.64Fe2O4. The effects of milling atmospheres （argon, air, and oxygen）, milling time （from 0 to 30 h） and heat treatment are studied. The products are characterized using x-ray diffractometry, field emission scanning electron microscopy equipped with energy-dispersive x-ray spectroscopy, and transmitted electron microscopy. The results indicate that the desired ferrite is not produced during the milling in the samples milled under either air or oxygen atmospheres. In those samples milled under argon, however, Zn/NiO/Fe2O3 reacts with a solid-state diffusion mode to produce Ni-Zn ferrite nanocrystalline in a size of 8 nm after 30-h-milling. The average crystallite sizes decrease to 9 nm and 10 nm in 30-h-milling samples under air and oxygen atmospheres, respectively. Annealing the 30-h-milling samples at 600℃ for 2 h leads to the formation of a single phase of Ni-Zn ferrite, an increase of crystallite size, and a reduction of internal lattice strain. Finally, the effects of the milling atmosphere and heating temperature on the magnetic properties of the 30-h-milling samples are investigated.

关键词： Ni-Zn ferrite nanocrystalline mechanical alloying milling atmosphere milling time magnetic property

Oxidation-induced ortho-selective C–H bond functionalization of 2-naphthylamine derivative

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Science China Chemistry 2018年第10期61卷 1274-1277页

作者： Dongchao Zhang Zhiliang Huang Aiwen Lei The institute for advanced Studies College of Chemistry and Molecular Sciences Wuhan University National Research Center for Carbohydrate synthesis Jiangxi Normal University

Selective C–H bond functionalization has been emerged as a versatile strategy for the construction of new chemical bonds. In the past decades, the directing group(DG)-assisted C–H bond activation has been developed as one of the most efficient methods for selective C–H functionalization. Although a great progress has been made by utilizing this traditional method, developing new strategy for selective C–H bond functionalization is still highly demanded. Hence, a novel oxidation-induced C–H bond functionalization method was demonstrated in this work. By this new method, ortho-C(sp2)–H chlorination of N-substituted 2-naphthylamine was realized in a highly selective manner.

关键词： oxidation-induced C-H bond functionalization ortho-selectivity

Modulating the alloying mode in the doping-induced synthesis of Au-Pd nanowires

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Nano Research 2024年第4期17卷 3334-3343页

作者： Hui Jin Xiaoliang Wei Lecheng Zhao Jialong Yu Qiao Pan Shumin Li Qian Wang Zhaotong Yuan Dan Yang Donghui Zhao Hongyu Chen Yawen Wang institute of advanced synthesis School of Chemistry and Molecular EngineeringJiangsu National Synergistic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjing 211816China School of Science Westlake UniversityHangzhou 310064China institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310064China

Heterogeneous doping is one effective strategy for synthesizing metal alloy ***,the heterogeneous doping processes of Pd on the ultrathin Au nanowires were systematically modulated and ***-Pd alloy nanowires with various morphologies and lattice structures can be obtained by adjusting the morphology of the precursor Au nanowires and the kinetics of the heterogeneous doping *** effects of the rate of Pd reduction and the concentration of the ligand oleylamine(OAm)on the Pd deposition and alloying mode were ***,as the Pd deposition rate decreases,the Pd deposition and alloying mode switches from the island-forming Stransky–Krastanov(SK)mode to the epitaxial Frank-van der Merwe(FM)mode,and eventually to an unconventional twisting alloying mode,where the interdiffusion of Pd and Au causes drastic rearrangement of the lattice structure and formation of helical *** kinetics-related variation of alloying mode could also be observed in the Au-Ag nanowires,demonstrating a general design principle for the synthesis of alloy *** addition,the electrocatalytic performance of various Au-Pd nanowires was evaluated,and the alloy nanowire formed via the SK mode was found to be an excellent electrocatalyst for oxygen reduction and ethanol oxidation.

关键词： gold nanowires Au-Pd alloy oleylamine post-synthetic modification

synthesis of ZrC Nanoparticles in the ZrO_2–Mg–C–Fe System Through Mechanically Activated Self-Propagating High-Temperature synthesis

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Acta Metallurgica Sinica(English Letters) 2014年第6期27卷 1144-1151页

作者： Abdollah Hajalilou Mansor Hashim Halimah Mohamed kamari Kazem Javadi Samikannu Kanagesan Mohammad Parastegari Materials synthesis and Characterization Laboratory Institute of Advanced Technology (ITMA) University Putra Malaysia Physics Department University Putra Malaysia Irankhodrow Industry Mechanical Testing Laboratory Materials synthesis and Characterization Laboratory Isfahan University of Technology

ZrC nanoparticles in the matrix of Fe were produced by the mechanically activated self-propagating hightemperature method using ZrO2/C/Mg/Fe powder mixtures. The effects of milling time, Fe content, and combustion temperature as well as the formation route for synthesizing ZrC powder particles were studied. The samples were characterized by XRD, SEM, TEM, and DTA. The XRD results revealed that, after 18 h of mechanical activation, ZrO2/ZC/Mg/Fe reacted with the self-propagating combustion（SHS） mode at 870 °C producing the ZrC–Fe nanocomposite. It was also found that both mechanical activation and Fe content played key roles in the ZrC synthesis temperature. With a Fe content of（5–40） wt%, the SHS reaction proceeded favorably and both the ZrC formation temperature and the adiabatic temperature（Tad） decreased. The Mg O content was removed from the final products using a leaching test process by dissolving in hydrochloric and acetic acids.

关键词： Mechanical activation(MA) Combustion synthesis Fe–ZrC composite Leaching process

Preparation and Microstructure of Porous ZrB_2 Ceramics Using Reactive Spark Plasma Sintering Method

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Journal of Wuhan University of Technology(Materials Science) 2015年第3期30卷 512-515页

作者：袁辉平李俊国 SHEN Qiang ZHANG Lianmeng State Key Laboratory of advanced Technology for Materials synthesis and Processing Wuhan University of Technology Beijing Glass Research institute

Zirconium oxide （ZrO：） and boron carbide （B4C） were added to ZrB2 raw powders to prepare ZrB2 porous ceramics by reactive spark plasma sintering （RSPS）. The reactions between ZrO2 and B,C which produce ZrB2 and gas （such as CO and B2O3） result in pore formation. X-Ray Diffraction results indicated that the products phase was ZrB2 and the reaction was completed after the RSPS process. The porosity could be controlled by changing the ratio of synthesized ZrB2 to raw ZrB2 powders. The porosity of porous ceramics with 20 wt% and 40 wt% synthsized ZrB2 are 0.185 and 0.222, respectivly. And dense ZrB：SiC ceramic with a porosity of 0.057 was prepared under the same conditions for comparison. The pores were homogeneously distributed within the microstructure of the porous ceramics. The results indicate a promising method for preparing porous ZrB：based ceramics.

关键词： zirconium diboride porous ceramic reactive spark plasma sintering

SIMULATION OF ELECTRICAL FIELD FOR THE FORMATION MECHANISM OF BIRD'S NEST PATTERNED STRUCTURES BY ELECTROSPINNING

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Chinese Journal of Polymer Science 2013年第3期31卷 514-520页

作者： Xiang-yu Ye Yi-ning Jin Xiao-jun Huang Lei Luo 徐志康 MOE Key Laboratory of Macromolecular synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University institute of advanced Digital Technology and Instrument Zhejiang University

In our previous work, it was found that large electrospun from chlorinated polypropylene solution doped Bird＇s Nest patterned nanofibrous membranes can be simply with an ionic liquid, and a plausible formation mechanism of Bird＇s Nest patterned architectures was proposed. Here, we use Ansoft Maxwell version 12 software （3D, electrostatic solver） to simulate the electrical field distribution of the electrospinning setup, and to clarify the rationality of proposed formation mechanism. Calculation results clearly show that the introduction of charged nanofibrous bundles would produce a similar patterned electrical field distribution, which definitely confirms the important role of surface residual charges. The proposed mechanism can be well extended to other polymer systems including polystyrene, poly（acrylonitrile-co-acrylic acid） and chitosan/poly（ethylene oxide）.

关键词： Electrospinning Patterned structures Finite element analysis Electrical field Theoretical simulation.

Self-templating synthesis of Pd_(4)S hollow nanospheres as electrocatalysts for oxygen reduction reaction

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Nano Research 2023年第2期16卷 2597-2603页

作者： Qian Wang Donghui Zhao Jialong Yu Lijie Shi Yawen Wang Hongyu Chen institute of advanced synthesis School of Chemistry and Molecular EngineeringNanjing Tech UniversityNanjing 211816China School of Science Westlake UniversityHangzhou 310023China

Hollow nanostructures with structural advantages have been widely exploited as catalysts in electrochemical ***,there are only limited strategies for constructing hollow Pd-based *** this work,Pd4S hollow nanospheres(Pd4S HNSs)are synthesized with a facile wet-chemical method via a self-templating *** Pd-L-cysteine solid nanospheres(SNSs)were firstly obtained by the coordination of L-cysteine with Pd^(2+),and then in situ converted to hollow nanospheres in the following reduction *** formation mechanism of the Pd4S HNSs was studied,and the size of the Pd4S HNSs can be readily adjusted by tuning the size of the *** hollow morphology would help the exposure of active sites and the prevention of aggregation during the catalytic *** a result,the Pd4S HNSs exhibit improved catalytic performances in the oxygen reduction reactions,with a half-wave potential of 0.913 V *** hydrogen electrode(RHE)and impressive stability in the accelerated durability test.

关键词： Pd4S hollow nanospheres self-templating electrocatalysis oxygen reduction reaction

Aggregation-amplified circularly polarized luminescence from axial chiral boron difluoride complexes

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Science China Chemistry 2019年第3期62卷 355-362页

作者： Zhiyong Jiang Xiaoqing Wang Jianping Ma Zhipeng Liu Key Laboratory of Flexible Electronics Institute of Advanced Materials Nanjing Tech University institute of advanced synthesis School of Chemistry and Molecular Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials Nanjing Tech University School of Chemistry & Cheimcal Engineering and Materials Science Shandong Normal University

The development of small organic molecules with intense and switchable circularly polarized luminescence(CPL) is currently attracting great interest due to their promising applications in chiroptical devices and sensors. In this paper, CPL-active BF2-bridged azaanthracene dimers(BA1 and BA2) were facilely synthesized by incorporating boron difluoride unit to the binaphthalene. BA1 and BA2 show moderate CPL in diluted solutions, however, BA2 exhibited aggregation-amplified red CPL with large dissymmetry factor up to 1.6×10^(-2). Moreover, acid-/base-triggered CPL switch off/on were also realized via disaggregation/aggregation of BA2 in tetrahydrofuran(THF)/water binary solvents.

关键词： aggregation-induced emission bodipy circularly polarized luminescence dyes and pigments switch