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中国有色金属学会会刊：英文版 2009年第4期19卷 1018-1022页

作者： Jae-Hyun NOH Kwan-Yo ung lee joong-kee lee Battery Research Center Korea Institute of Science and Technology Department of Chemical and Biological Engineering Korea University

Phosphorus doped silicon-carbon composite particles were synthesized through a DC arc plasma ***(SiH4) and methane(CH4) were introduced into the reaction chamber as the precursor of silicon and carbon,***(PH3) was used as a phosphorus dopant *** of synthesized particles were carried out by scanning electron microscopy(SEM),X-ray diffractometry(XRD),X-ray photoelectron spectroscopy(XPS) and bulk resistivity *** properties were investigated by cyclic test and electrochemical voltage spectroscopy(EVS).In the experimental range,phosphorus doped silicon-carbon composite electrode exhibits enhanced cycle performance than intrinsic silicon and phosphorus doped *** can be explained that incorporation of carbon into silicon acts as a buffer matrix and phosphorus doping plays an important role to enhance the conductivity of the electrode,which leads to the improvement of the cycle performance of the cell.

关键词：电化学特性磷掺杂负极活性材料磷硅电池材料锂离子 X射线光电子能谱扫描电子显微镜

Employment of encapsulated Si with mesoporous TiO_2 layer as anode material for lithium secondary batteries

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中国有色金属学会会刊：英文版 2009年第4期19卷 1023-1026页

作者： Sang-Eun PARK Bo-Eun KIM Sang-Wha lee joong-kee lee Advanced Energy Materials Processing Laboratory Korea Institute of Science and Technology Department of Chemical & Bio Engineering Kyungwon University

Silicon composite of nano-capsule type is newly applied as an active anode material for lithium ion ***2-encapsulated silicon powders were synthesized by a sol-gel reaction with titanium *** nanoparticles were successfully embedded into porous titanium oxide capsules that played as a buffer layer against drastic volume changes of silicon during the charge-discharge cycling,consequently leading to the retardation of the capacity fading of intrinsic silicon *** electrochemical and structural properties of silicon nanocomposites with different surface areas of encapsulating TiO2 layer were characterized by X-ray diffraction(XRD),nitrogen gas adsorption analysis by the Brunauer-Emmett-Teller(BET) equation,transmission electron microscopy(TEM),and galvanostatic charge-discharge experiments.

关键词：二氧化钛硅材料锂二次电池负极材料封装纳米复合材料透射电子显微镜就业

Stable Zn Metal Anodes with Limited Zn-Doping in MgF_(2) Interphase for Fast and Uniformly Ionic Flux

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Nano-Micro Letters 2022年第3期14卷 169-183页

作者： Ji Young Kim Guicheng Liu Ryanda Enggar Anugrah Ardhi Jihun Park Hansung Kim joong kee lee Energy Storage Research Center Korea Institute of Science and TechnologyHwarang‑ro 14‑gil 5Seongbuk‑guSeoul 02792Republic of Korea Department of Chemical and Biomolecular Engineering Yonsei University50 Yonsei‑roSeodaemun‑guSeoul 03722Republic of Korea Department of Physics Dongguk UniversitySeoul 04620Republic of Korea APC Technology 10868 Gangbyeonyeok‑ro‑4‑gilGwangjin‑guSeoul 05116Republic of Korea Department of Energy and Environmental Engineering KIST SchoolKorea University of Science and TechnologyHwarang‑ro 14‑gil 5Seongbuk‑guSeoul 02792Republic of Korea

The practical applications of aqueous Zn metal batteries are currently restricted by the inherent drawbacks of Zn such as the hydrogen evolution reaction,sluggish kinetics,and dendrite *** address these problems,herein,a limitedly Zn-doped MgF_(2)interphase comprising an upper region of pure,porous MgF_(2)and a lower region of gradient Zn-doped MgF_(2)is achieved via radio frequency sputtering *** porous MgF_(2)region is a polar insulator whose high corrosion resistance facilitates the de-solvation of the solvated Zn ions and suppression of hydrogen evolution,resulting in Zn metal electrodes with a low interfacial *** Zn-doped MgF_(2)region facilitates fast transfer kinetics and homogeneous deposition of Zn ions owing to the interfacial polarization between the Zn dopant and MgF_(2)matrix,and the high concentration of the Zn dopant on the surface of the metal substrate as fine ***,a symmetric cell incorporating the proposed Zn metal exhibits low overpotentials of~27.2 and~99.7 mV without Zn dendrites over 250 to 8000 cycles at current densities of 1.0 and 10.0 mA cm−2,*** developed Zn/MnO2 full cell exhibits superior capacity retentions of 97.5%and 84.0%with average Coulombic efficiencies of 99.96%after 1000 and 3000 cycles,respectively.

关键词： Zinc metal battery MgF_(2)layer Limited zinc doping Ion-transfer kinetic Deposition guidance

Effect of metal catalyst on the mechanism of hydrogen spillover in three-dimensional covalent-organic frameworks

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Chinese Physics B 2017年第2期26卷 412-419页

作者： Xiu-Ying Liu Jing-Xin Yu Xiao-Dong Li Gui-Cheng Liu Xiao-Feng Li joong-kee lee College of Science Henan University of Technology Zhengzhou 450000 China Center for Energy Convergence Research Green City Research Institute Korea Institute of Science and Technology (KIST) Seou102792 Republic of Korea College of Physical and Electronic Information Luoyang Normal University Luoyang 471022 China

Hydrogen spillover mechanism of metal-supported covalent-organic frameworks COF-105 is investigated by means of the density functional theory, and the effects of metal catalysts M_4（Pt_4, Pd_4, and Ni_4） on the whole spillover process are systematically analyzed. These three metal catalysts exhibit several similar phenomena：（i） they prefer to deposit on the tetra（_4-dihydroxyborylphenyl） silane（TBPS） cluster with surface-contacted configuration;（ii） only the H atoms at the bridge site can migrate to 2,3,6,7,10,11-hexahydroxy triphenylene（HHTP） and TBPS surfaces, and the migration process is an endothermic reaction and not stable;（iii） the introduction of M_4 catalyst can greatly reduce the diffusion energy barrier of H atoms, which makes it easier for the H atoms to diffuse on the substrate surface. Differently, all of the H2 molecules spontaneously dissociate into H atoms onto Pt_4 and Pd_4clusters. However, the adsorbed H2 molecules on Ni_4 cluster show two types of adsorption states： one activated state with stretched H–H bond length of 0.88 ？A via the Kubas interaction and five dissociated states with separated hydrogen atoms. Among all the M_4 catalysts, the orders of the binding energy of M_4 deposited on the substrate and average chemisorption energy per H2 molecule are Pt_4〉Ni_4〉Pd_4. On the contrary, the orders of the migration and diffusion barriers of H atoms are Pt_4

关键词： covalent-organic frameworks hydrogen spillover hydrogen storage density functional theory

Uniform Metal Sulfide@N-doped Carbon Nanospheres for Sodium Storage: Universal Synthesis Strategy and Superior Performance

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Energy & Environmental Materials 2023年第2期6卷 389-396页

作者： Kai Yang Hao Fu Yixue Duan Manxiang Wang Minh Xuan Tran joong kee lee Woochul Yang Guicheng Liu Department of Physics Dongguk UniversitySeoul 04620Korea Shaanxi Key Laboratory of Chemical Additives for Industry Shaanxi University of Science and TechnologyXi’an 710021China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China College of Physics and Electronic Information Yan’an UniversityYan’an 716000China Center for Energy Storage Research Clean Energy InstituteKorea Institute of Science and Technology(KIST)Seoul 02792Korea

Nitrogen-doped carbon-coated transition-metal sulfides(TMS@NCs)have been considered as efficient anodes for sodium-ion ***,the uncontrollable morphology and weak core-shell binding forces significantly limit the sodium storage performance and ***,based on the reversible ring-opening reaction of the epoxy group of the tertiary amino group-rich epoxide cationic polyacrylamide(ECP)at the beginning of hydrothermal process(acidic environment)and the irreversible ring-opening(cross-linking reactions)at the late hydrothermal period(alkaline environment),47 nm-sized ZnS@NCs were prepared via a one-pot hydrothermal *** this process,the covalent bonds formed between the ZnS core and elastic carbon shell significantly improved the mechanical and chemical stabilities of ZnS@*** from the nanosize,fast ion/electron transfer,and high stability,ZnS@NC exhibited a high reversible capacity of 421.9 mAh g^(−1) at a current density of 0.1 A g^(−1) after 1000 cycles and a superior rate capability of 273.8 mAh g^(−1) at a current density of 5 A g^(−1).Moreover,via this universal synthesis strategy,a series of TMS@NCs,such as MoS_(2)@NC,NiS@NC,and CuS@NC were developed with excellent capacity and cyclability.

关键词： anode materials core-shell structure nitrogen-doped carbon ring-opening reaction transition-metal sulfide

Reversible Zn/polymer heterogeneous anode

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Carbon Energy 2023年第6期5卷 82-91页

作者： Lingyun Xiong Hao Fu Kai Yang Ji Young Kim Ren Ren joong kee lee Woochul Yang Guicheng Liu Department of Physics Dongguk UniversitySeoulRepublic of Korea School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijingChina Energy Storage Research Center Clean Energy InstituteKorea Institute of Science and Technology(KIST)Seongbuk‐guSeoulRepublic of Korea Department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina

Commercialization of Zn-metal anodes with low cost and high theoretical capacity is hindered by the poor reversibility caused by dendrites growth,side reactions,and the slow Zn^(2+)-transport and reaction ***,a reversible heterogeneous electrode of Zn-nanocrystallites/polyvinylphosphonic acrylamide(Zn/PPAm)with fast electrochemical kinetics is designed for the first time:phosphonic acid groups with strong polarity and chelation effect ensure structural reversibility and stability of the threedimensional Zn-storage-host PPAm network and the Zn/PPAm hybrid;hydrophobic carbon chains suppress side reactions such as hydrogen evolution and corrosion;weak electron-donating amide groups constitute Zn^(2+)-transport channels and promote“desolvation”and“solvation”effects of Zn^(2+)by dragging the PPAm network on the Zn-metal surface to compress/stretch during Zn plating/stripping,respectively;and the heterostructure and Zn nanocrystallites suppress dendrite growth and enhance electrochemical reactivity,***,the Zn/PPAm electrode shows cycle reversibility of over 6000 h with a hysteresis voltage as low as 31 mV in symmetrical cells and excellent durability and flexibility in fiber-shaped batteries.

关键词： dendrite-free electrode process kinetics fiber-shaped battery reversible metal/polymer heterostructure Zn-metal anode

Ordered SnO nanoparticles in MWCNT as a functional host material for high-rate lithium-sulfur battery cathode

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Nano Research 2017年第6期10卷 2083-2095页

作者： A-Young Kim Min Kyu Kim Ji Young Kim Yuren Wen Lin Gu Van-Duong Dao Ho-Suk Choi Dongjin Byun joong kee lee Center for Energy Convergence Korea Institute of Science and Technology Seoul02792 Republic of Korea Department of Material Science and Engineering Korea University Seoul 02841 Republic of Korea Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Department of Chemical Engineering & Applied Chemistry Chungnam National University Daejeon 34134 Republic of Korea

Lithium-sulfur battery has become one of the most promising candidates for next generation batteries, and it is still restricted due to the low sulfur conductivity, large volume expansion and severe polysulfide shuttling. Herein, we present a novel hybrid electrode with a ternary nanomaterial based on sulfur-impregnated multiwalled carbon nanotubes filled with ordered tin-monoxide nanoparticles （MWCNT-SnO/S）. Using a dry plasma reduction method, a mechanically robust material is prepared as a cathode host material for lithium-sulfur batteries. The MWCNT-SnO/S electrode exhibits high conductivity, good ability to capture polysulfides, and small volume change during a repeated charge-discharge process. In situ transmission electron microscopy and ultraviolet-visible absorption results indicate that the MWCNT-SnO host efficiently suppresses volume expansion during lithiation and reduces polysulfide dissolution into the electrolyte. Furthermore, the ordered SnO nanoparticles in the MWCNTs facilitate fast ion/electron transfer during the redox reactions by acting as connective links between the walls of the MWCNTs. The MWCNT-SnO/S cathode with a high sulfur content of 70 wt.% exhibits an initial discharge capacity of 1,682.4 mAh·g^-1 at 167.5 m·g^-1 （0.1 C rate） and retains a capacity of 530.1 mAh·g^-1 at 0.5 C after 1,000 cycles with nearly 100% Coulombic efficiency. Furthermore, the electrode exhibits the high capacity even at a high current rate of 20 C.

关键词： hybrid nanomaterial multiwalled carbonnanotube (MWCNT) ordered tin monoxide cathode high loading lithium-sulfur battery

Recent Advances in Patterning Strategies for Full‑Color Perovskite Light‑Emitting Diodes

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Nano-Micro Letters 2024年第3期16卷 99-137页

作者： Gwang Heon lee Kiwook Kim Yunho Kim Jiwoong Yang Moon kee Choi Graduate School of Semiconductor Materials and Devices Engineering Center for Future Semiconductor Technology(FUST)Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Republic of Korea Department of Energy Science and Engineering Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Republic of Korea Energy Science and Engineering Research Center Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Republic of Korea Department of Materials Science and Engineering Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Republic of Korea Center for Nanoparticle Research Institute for Basic Science(IBS)Seoul 08826Republic of Korea

Metal halide perovskites have emerged as promising light-emitting materials for next-generation displays owing to their remarkable material characteristics including broad color tunability,pure color emission with remarkably narrow bandwidths,high quantum yield,and solution *** recent advances have pushed the luminance efficiency of monochromic perovskite light-emitting diodes(PeLEDs)to their theoretical limits,their current fabrication using the spincoating process poses limitations for fabrication of full-color *** integrate PeLEDs into full-color display panels,it is crucial to pattern red–green–blue(RGB)perovskite pixels,while mitigating issues such as cross-contamination and reductions in luminous ***,we present state-of-the-art patterning technologies for the development of full-color ***,we highlight recent advances in the development of efficient ***,we discuss various patterning techniques of MPHs(i.e.,photolithography,inkjet printing,electron beam lithography and laserassisted lithography,electrohydrodynamic jet printing,thermal evaporation,and transfer printing)for fabrication of RGB pixelated *** patterning techniques can be classified into two distinct approaches:in situ crystallization patterning using perovskite precursors and patterning of colloidal perovskite *** review highlights advancements and limitations in patterning techniques for PeLEDs,paving the way for integrating PeLEDs into full-color panels.

关键词： Perovskite Light-emitting diode Full-color display High-resolution patterning Electroluminescence

Ionizing terahertz waves with 260 MV/cm from scalable optical rectification

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Light(Science & Applications) 2024年第6期13卷 1075-1087页

作者： Hyeongmun Kim Chul Kang Dogeun Jang Yulan Roh Sang Hwa lee joong Wook lee Jae Hee Sung Seong Ku lee Ki-Yong Kim Advanced Photonics Research Institute GISTGwangju61005Korea Department of Physics and Optoelectronics Convergence Research Center Chonnam National UniversityGwangju61186Korea Pohang Accelerator Laboratory POSTECHPohang37673Korea Center for Relativistic Laser Science Institute for Basic ScienceGwangju61005Korea Institute for Research in Electronics and Applied Physics Department of PhysicsUniversity of MarylandCollege ParkMaryland20742USA

Terahertz(THz)waves,known as non-ionizing radiation owing to their low photon energies,can actually ionize atoms and molecules when a sufficiently large number of THz photons are concentrated in time and ***,we demonstrate the generation of ionizing,multicycle,15-THz waves emitted from large-area lithium niobate crystals via phase-matched optical rectification of 150-terawatt laser pulses.A complete characterization of the generated THz waves in energy,pulse duration,and focal spot size shows that the field strength can reach up to 260 megavolts per *** particular,a single-shot THz interferometer is employed to measure the THz pulse duration and spectrum with complementary numerical *** intense THz pulses are irradiated onto various solid targets to demonstrate THz-induced tunneling ionization and plasma *** study also discusses the potential of nonperturbative THz-driven ionization in gases,which will open up new opportunities,including nonlinear and relativistic THz physics in plasma.

关键词： optical interferometer matched

Physically active primary care physicians consult more on physical activity and exercise for patients: A public teaching-hospital study

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Sports Medicine and Health Science 2024年第1期6卷 82-88页

作者： Ann kee lee Rosediani Bt Muhamad Vina Phei Sean Tan Exercise&Sports Science School of Health SciencesHealth CampusUniversiti Sains Malaysia16150Kubang KerianMalaysia Department of Family Medicine School of Medical SciencesHealth CampusUniversiti Sains Malaysia16150Kubang KerianMalaysia

Physical activity and exercise(PAE)improve quality of life and reduce the effects of chronic *** care physicians(PCPs)play an important role to encourage PAE in *** aim to assess PCPs'current PAE consultation practices and their enablers/barriers in daily clinical *** had 64 PCPs(age[35.3±4.7]y,47 women)that completed self-administered questionnaires on PAE consultation practices,training,and confidence ***(n=42)also completed the International Physical Activity Questionnaire-Short Form to assess their physical activity(PA)*** conducted correlation,one-way analysis of variance and a linear regression to assess the associations between enablers,barriers and PA levels to PAE consultation *** average,PCPs consulted on PAE in 49.7%of their daily clinical *** of PCPs(70%)strongly agreed that more PAE knowledge were needed to increase consultation *** three barriers related(p<0.001)to practices were lack of PAE education(r=0.47),patients’preference of pharmaceutical interventions(r=0.45)and lack of continuing education in PAE for PCPs(r=0.37).Physically active PCPs(health-enhancing PA levels,n=6)gave significantly more daily consultations in PAE,73.2%±21.9%,compared to inactive PCPs(n=13),37.4%22.8%(p=0.013).In our regression output,PCPs who had higher PA levels consulted more on PAE daily(R^(2)=0.38,p<0.001)while controlling for ***,PCPs require more knowledge on PAE and need be physically active themselves to increase PAE consultation for patients in their daily *** education should consider including more PA and exercise topics that may benefit both physicians and their patients.

关键词： Physical activity and exercise Primary care physicians Consultations Exercise prescription Medicine