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Journal of Energy Chemistry 2020年第2期29卷 73-78页

作者： Xiaoyan Xu Yuanyuan Li Jun Cheng Guangmei Hou Xiangkun Nie Qing Ai Linna Dai Jinkui Feng Lijie Ci SDU& Rice Joint Center for Carbon nanomaterials Key Laboratory for Liquid-Solid Structural Evolution&Processing of Materials(Ministry of Education)School of Materials Science and EngineeringShandong UniversityJinan 250061ShandongChina

High ionic conductivity and superior interfacial stability of solid electrolytes at the electrodes are crucial factors for high-performance all-solid-state sodium batteries. Herein, a composite solid electrolyte na3PS4-polyethylene oxide is synthesized by the solution-phase reaction method with an improved ionic conductivity up to 9.4 × 10-5 S/cm at room temperature. Moreover, polyethylene oxide polymer layer is wrapped homogeneously on the surface of na3PS4 particles, which could effectively avoid the direct contact between na3PS4 electrolyte and sodium metal, thus alleviate their side reactions. We demonstrate that all-solid-state battery SnS2/na with the composite solid electrolyte na3PS4-polyethylene oxide delivers an enhanced electrochemical performance with 230 m Ah/g after 40 cycles.

关键词： Composite solid electrolyte na 3PS4 All-solid-state sodium battery SnS2

Enhancement of green emission by the codoping A^+ (A= Li, na, K) in Ca_2BO_3Cl:Tb^(3+) phosphor

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Chinese Physics B 2013年第8期22卷 663-666页

作者：李盼来徐征赵谡玲张福俊王永生 Institute of Optoelectronics Technology Beijing Jiaotong University Key Laboratory of Luminescence and Optical Information Ministry of Education Beijing Jiaotong University College of Physics Science & Technology Hebei University

Tb3＋-doped Ca2BO3C1 compounds with different charge compensation approaches are synthesized by a hightemperature solid-state reaction method, and the luminescent properties and Commission Internationale de l＇Eclairage （CIE） chromaticity coordinates are systematically characterized. Ca2BO3Cl：Tb3＋ can produce green emission under 376 nm radiation excitation. With codoped A＋（A = Li, na, K） as charge compensators, the relative emission intensities of Ca2BO3Cl：Tb3＋ are enhanced by about 1.61, 1.97, and 1.81 times compared with those of the direct charge balance, which is considered to be due to the effect of the difference in ion radius on the crystal field. The CIE chromaticity coordinates of Ca2BO3CI：Tb3＋, A＋（A = Li, na, K） are （0.335, 0.584）, （0.335, 0.585）, and （0.335, 0.585）, corresponding to the hues of green. Therefore, A＋（A = Li, na, K） may be the optimal charge compensator for Ca2BO3Cl：Tb3＋.

关键词： luminescence Ca2BO3CI:Tb3+ A+ (A = Li na K)

Kinetics and Thermodynamic Parameters of the CopperExchange on na-montmorillonite Clay Mineral inSelected Solvents

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Journal of Materials Science & Technology 1995年第4期11卷 265-268页

作者： A.A.Zaghlou M.EI-Batouty and Sh.A.Shazly (Chemistry Dept., Faculty of Science, Alexandria University, Alexandria, Egypt) Alexandria Univ Alexandria Egypt

The kinetics of Cu ion exchange on na-montmorillonite clay mineral has been investigated at three temperatures, in three solvents: H2O, ethylene glycol and glycerol. Solvent effects on the reaction rate have been discussed. The thermodynamic activation parameters were calculated and discussed in terms of solvation effects. The determined isokinetic temperature indicates that the reaction is enthalpy controlled where the interaction between solvent and clay surface plays an important role. A reaction mechanism which describes the solvent effect on the rate of Cu ion exchange is proposed.

关键词： na Kinetics and Thermodynamic Parameters of the CopperExchange on na-montmorillonite Clay Mineral inSelected Solvents

Relationship between CO_2 Sensor Voltage Response and Phase Equilibrium of Solid Electrolyte na,K-β/β″-Al_2O_3

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Journal of Materials Science & Technology 2003年第5期19卷 450-452页

作者： J.H.YANG H.nafe F.Aldinger D.S.YAN ShanghaiInstituteofCeramics ChineseAcademyofSciencesShanghai200050China Max-Planck-InstitutfurMetallforschung PulvermetallurgischesLaboratoratiumHeisenbergstrasse570569StuttgartGermany

关键词： CO2 sensor Phase equilibrium Solid electrolyte na K-β/β'-Al2O3

Negative Thermal Expansion of GaFe(CN)_6 and Effect of na Insertion by First-Principles Calculations

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Chinese Physics Letters 2019年第6期36卷 37-40页

作者： Meng Li Yuan Li Chun-Yan Wang Qiang Sun International Laboratory for Quantum Functional Materials of Henan School of Physics and EngineeringZhengzhou University

We study the negative thermal expansion(NTE) properties and effect of na insertion on the NTE of the framework material GaFe(CN)_6 by first-principles calculations based on density functional theory within the quasi-harmonic approximation. The calculated results show that the material exhibits NTE due to the low transverse vibrational modes of the CN groups. The modes demonstrate larger negative values of the mode Grüneisen parameters. Once na is introduced in the framework of the material, it prefers to locate at the center of the quadrates of the framework material and binds to the four N anions nearby. As a consequence, the transverse vibrational mode of the CN group is clearly hindered and the NTE of the material is weakened. Our theoretical calculations have clarified the mechanisms of NTE and the effect of the guest na on the NTE of the framework material.

关键词： negative thermal expansion(NTE) na Insertion First-Principles Calculations

Potential Barrier Behavior of BaTiO3-(Bi0.5na0.5)TiO3 Positive Temperature Coefficient of Resistivity Ceramic

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Chinese Physics Letters 2015年第4期32卷 90-93页

作者：冷森林石维李国荣郑嘹赢 Institute of Physics and Electronics Engineering Tongren University Tongren 554300 Key Laboratory of Inorganic Functional Materials and Devices Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050

High-Curie-temperature （Tc） lead-free Y-doped 90 mol%BaTiO3-1O mol%（Bi0.5na0.5 ） TiO3 ceramic with positive temperature coefficient of resistivity （PTCR） is prepared by the conventional solid state reaction in nitrogen atmosphere. The PTCR ceramic exhibits a room-temperature resistivity （p25） of ~500Ω.cm and a high PTCR effect （maximum resistivity （ρmax）/minimum resistivity （ρmin）） of ~4.5 orders of magnitude. A capacitance- voltage approach is first employed to calculate the potential barrier （ Ф ） of the grain boundary of PTCR ceramic above Tc. It is found that the potential barrier changes from 0.17 to 0.77eV as the temperature increases from 180 to 220℃, which is very close to the predictions of the Heywang-Jonker model, suggesting that the capacitance-voltage method is valid to estimate the potential barrier of PTCR thermistor ceramics.

关键词： Potential Barrier Behavior of BaTiO3 na Bi

A High-Temperature β-Phase naMnO2 Stabilized by Cu Doping and Its na Storage Properties

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Chinese Physics Letters 2018年第4期35卷 132-135页

作者： Li-Wei Jiang Ya-Xiang Lu Yue-Sheng Wang Li-Lu Liu Xing-Guo Qi Cheng-Long Zhao Li-Quan Chen Yong-Sheng Hu Key Laboratory for Renewable Energy Beijing Key Laboratory for New Energy Materials and Devices and BeijingNational Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049

The high-temperature β-phase naMnO2 is a promising material for na-ion batteries（NIBs） due to its high capacity and abundant resources. However, the synthesis of phase-pure -naMnO2 is burdensome and costineffective because it needs to be sintered under oxygen atmosphere at high temperature and followed by a quenching procedure. Here we first report that the pure β phase can be stabilized by Cu-doping and easily synthesized by replacing a proportion of Mn with Cu via a simplified process including sintering in air and cooling to room temperature naturally. Based on the first-principle calculations, the band gap decreases from 0.7 eV to 0.3 eV, which indicates that the electronic conductivity can be improved by Cu-doping. The designed -naCu（0.1）Mn（0.9）O2 is applied as cathode in NIBs, exhibiting an energy density of 419 Wh/kg and better performance in terms of rate capability and cycling stability than those in the undoped case.

关键词： na A High-Temperature Phase naMnO2 Stabilized by Cu Doping and Its na Storage Properties Mn Cu

Improving luminescent property of SrIn_2 O_4 :Eu^(3+) by co-doped A^+ (A = Li, na, K) or Sm^(3+)

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Chinese Physics B 2013年第4期22卷 495-499页

作者：王志军李盼来杨志平郭庆林 College of Physics Science & Technology Hebei University

A series of SrIn2 O4 ：Eu^3＋ phosphors are synthesized by a high temperature solid-state method, and their luminescent properties are investigated. They can be excited by 395-nm radiation, and produce red emission （619 nm）; however, they have a low absorption of near-ultraviolet light with the wavelength of 400nm–405 nm. When co-doped with A^＋（A=Li, na, K）, the emission intensity of SrIn2O4 ：Eu^3＋ is significantly enhanced, but its emission and excitation spectral profile is unchanged. With co-doping Sm^3＋ , not only is the emission intensity of SrIn2 O4 ：Eu^3＋ enhanced, but also the absorption is broadened and strengthened in the range of 400 nm–405nm. The effect of Sm^3＋ -doped content on the emission intensity of SrIn2O4 ：Eu^3＋ , Sm^3＋ is investigated, and the optimal Sm^3＋ content is 0.02 mol.

关键词： luminescence SrIn2O4 :Eu^3+ A+(A=Li na K) Sm^3+

Electronic Structure and Thermoelectric Power Factor of na_xCoO_2 from First-Principles Calculation

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Chinese Physics Letters 2017年第3期34卷 103-106页

作者：路朋献赵瑞霞 College of Materials Science and Engineering Henan University of Technology Department of Civil Engineering and Architecture Henan Technical College of Construction

To investigate the relationship between the electronic structure and the power factor of nax CoO2 （x = 0.3, 0.5 and 1.0）, the first-principles calculation is conducted by using density functional theory and the semi-classical Boltzmann theory. Our results suggest that with the decreasing na content, a transition from semiconductor to semimetal is observed. na0.3CoO2 possesses a higher electrical conductivity at 1000 K due to its increased density of states near the Fermi energy level. However, an optimal Seebeck coefficient at 1000 K is obtained in na0.5CoO2 because of its broadened band gap near the Fermi energy level Consequently, a maximum power factor is realized in na0.5CoO2. Thus our work provides a complete understanding of the relationship between the electronic structure and the thermoelectric power factor of nax CoO5.

关键词： na Co Seebeck

Electromagnetic effects of nearby na Cl solution on RFID tags based on dynamic measurement system

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The Journal of China Universities of Posts and Telecommunications 2015年第5期22卷 49-55页

作者： Huang Yu Yu Xiaolei Wang Donghua Wu Rui Jiangsu Institute of Standardization School of Electronic Science and Engineering Nanjing University of Posts and Telecommunications

We have studied the effects of nearby na Cl solution on the performance of ultra high frequency(UHF) radio frequency identification(RFID) tags, using simulations and measurements. The main reason for the decrease of read range in proximity to na Cl solution is the antenna gain penalty. The boundary conditions near the surface reduce antenna efficiency and antenna gain. With the conductivity of the na Cl solution increasing, the read range of the RFID system decreases. A theoretical formula is proposed for the read range to calculate the material losses of tag antenna. The formula establishes relationship between conductivity and read range of RFID system. The maximum read range is also calculated theoretically with simulation software. In addition, we develop an experimental measurement technique to certify the feasibility of the derived formula, which involves a dynamic measurement system. Consequently, the experimental results are found to be in good agreement with theoretical data.

关键词： radio frequency identification(RFID) read range na