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Progress in Natural Science:Materials International 2019年第3期29卷 256-264页

作者： Youwei Wang Erhong Song Wujie Qiu Xiaolin Zhao Yao Zhou Jianjun Liu Wenqing Zhang State Key Laboratory of High Performance ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of Sciences department of Physics and Shenzhen Institute for Quantum Science & Technology Southern University of Science and Technology

This review has been made an attempt to seek some observed descriptors to comprehensively optimize structural stability and catalytic activity of single-atom catalysts. Electronic structure analysis can reveal the underlying mechanisms of atomic phy-chemical properties and local coordination structures on binding strength. The free electrons around Fermi level play an important role to determine the binding strength, which can be further influenced by electronegativity difference between single atom and nearby support atoms. This investigation can contribute to understanding the underlying mechanisms for the design of stable and active catalysts, and further provide a deep insight to the potential pathways in the research field of single-atom catalysts.

关键词： SAC Recent progress in theoretical and computational investigations of structural stability and activity of single-atom electrocatalysts

Variation of Ti Valence with Lithium Content in Lithiated/Delithiated Li_(4)Ti_(5)O_(12) Studied by X-Ray Absorption near the Edge Structure

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Chinese Physics Letters 2013年第3期30卷 108-111页

作者： YU Peng-Fei CUI Zhong-Hui MENG Jian-Wei GUO Xiang-Xin State Key Laboratory of High Performance ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050 State Key Laboratory of ASIC and System Department of MicroelectronicsFudan UniversityShanghai 200433

Synchrotron-based x-ray absorption near-edge structure(XANES)spectroscopy is applied to investigate the variation of Ti valence in the discharge and charge processes of Li_(4)Ti_(5)O_(12).Through analysis of the XANES data,the average valence of Ti can be calculated,which allows quantitative determination of the ratios of Ti^(3+)/Ti^(4+) as a function of Li content in the *** is found that the ratios in the composites of Li_(4)Ti_(5)O_(12)/acetylene black(AB)-carbon are larger than those in Li_(4)Ti_(5)O_(12)/Ag/AB-carbon after the discharge to 1.1 V,indicating a larger amount of Li inserted into the former than that into the *** finding provides a good explanation for the fact that the Li_(4)Ti_(5)O_(12)/AB-carbon samples exhibit larger storage capacities than the Li_(4)Ti_(5)O_(12)/Ag/AB-carbon ones prepared in this work,concerning the larger Ti^(3+)/Ti^(4+) ratio and the larger amount of Li^(+) inserted in the electrode for satisfying the charge neutralization requirement.

关键词： Li_(4)Ti_(5)O_(12) composites XANES

TEM observation on nucleation of Ca α-Sialon

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Chinese Science Bulletin 2001年第3期46卷 216-219页

作者： Yawen Li Peiling Wang Weiwu Chen Jingwei Feng Dongsheng Yan Yibing Cheng State Key Laboratory of High Performance ceramics and Superfine Microstructure Shanghai Institute of Ceramics Shanghai China department of Materials Engineering Monash University Clayton Australia

Ca α-Sialon compacts pressurelessly-sintered tothe intermediate temperature (1 450℃) were investigated with TEM for an overall composition Ca1.8Si6.6Al5.4O1.8N14.2. It was found that in most cases, the newly-formed α-Sialon grains had no epitaxial orientation relationship with the Si3-N4 particles; only occasionally heteroepitaxial nucleation of α-Sialon on α-Si3N4 was detected. Further EDAX analysis revealed a much higher Ca concentration in the non-epi-taxially nucleated α-Sialon than in the heteroepitaxially nucleated α-Sialon. Thus a possible correlation between the concentration of metal cations in the (a-Sialon structure and the nucleation mechanism has been proposed, i.e. α-Sialon compositions with higher Ca concentration show a stronger trend of non-epitaxial nucleation.

关键词： Ca α-Sialon TEM nucleation mechanism.

Improvement of water resistance of long afterglow SrAl_2O_4: Dy, Eu phosphor by coating with SiO_2 film

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Rare Metals 2002年第2期21卷 152-155页

作者： ZHANG Junying, CHEN Qingming, LIN Yuanhua, and ZHANG ZhongtaiState Key Laboratory of New ceramics and Fine Processing, department of Materials Science and Engineering, Tsinghua University,Beijing 100084, China department of Materials Science and Engineering Tsinghua University State Key Laboratory of New Ceramics and Fine Processing 北京 100084

The long afterglow SrAl_2O_4: Dy, Eu phosphor is liable tohydrolyze in water with deterioration of the lumin- escent ***_2O_4: Dy, Eu phosphors were therefore heated at 60-90 deg. C inTEOS sol to form a surface gel and then heat-treated at 400 deg. C toobtain SiO_2 coated phosphors. Observation by ?Transmission ElectronMicroscope (TE) and X- ray photoelectron spectroscopy (XPS) showsthat a thin silica film forms on the surface of the phosphors. Thecoating procedure can be illustrated by a four-step process and thetransparent silica film can suppress the hydrolysis process, so thatthe luminescent properties of the phosphors are unimpaired or evenbetter.

关键词： phosphors coating luminescent materials SrAl_2O_4

Preparation and Characterization of Highly Oriented ZnO Film by Ultrasonic Assisted SILAR Method

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Journal of Wuhan University of Technology(Materials Science) 2005年第3期20卷 23-26页

作者：高相东 State Key Laboratory of High Performance ceramics and Superfine Microstructures Shanghai Institute of Ceramics of Chinese Academy of Sciences

Ultrasonic Assisted SILAR method （UA-SILAR） was developed and highly oriented ZnO films were deposited on the glass substrate by this novel technique. The crystallinity and microstructure of as-deposited ZnO films were analyzed by means of XRD and SEM. Moreover, the underling deposition mechanism of ZnO films was discussed. Results show that obtained ZnO films exhibit an excellent crystallinity with the preferentioal orientation of （002） plane. The crystalline grain of films is about 40nm in size,which is supported by both the Sherrer equation and the SEM result. However, the ZnO film is composed of numerous clustered purticulates in the size of 200 to 300nm, and each particulate is the compact aggregation of smaller ZnO crystalline grains. It is .speculated that the excellent crystallinity of ZnO films may chiefly originate from the cavatition effect of the ultrasonic rinsing process.

关键词： ZnO films U4- SILAR preparation

Melt Infiltration Ability and Microstructural Evolution of Fe40Al/ TiC Composites System

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厦门大学学报（自然科学版） 2002年第S1期41卷 93-页

作者： F J Oliveira J L Baptista J M Vieira department of ceramics and glass Engineering/CICECO University of AveiroDepartment of Ceramics and Glass Engineering/CICECO University of AveiroDepartment of Ceramics and Glass Engineering/CICECO University of Aveiro Po rtugal Po rtugal Po rtugal

Pressureless melt infiltration is an economic route f or preparation of high-density ceramic/melt composites. In this study, the Fe40 Al iron aluminide intermetallic, a low cost material of excellent oxidation and corrosion resistance, was used as binder for fabricating Fe40Al/TiC composites b y pressureless melt infiltration. The wetting ability of liquid Fe40Al in porous TiC pre-form was studied by in-situ monitoring the melting and infiltration p rocess. The infiltration ability was investigated by observing the distance of l iquid Fe40Al intrusion in porous TiC pre-forms at different infiltration temper atures and times by using optical microscope. Porous TiC per-forms with density of 60%～88%TD (theoretical density), prepared under pre-defined sintering temp e rature cycles, were used for fabricating Fe40Al/TiC composites in the range of 1 2%～40% metal content by volume. Almost full dense Fe40Al/TiC composites were su c cessfully fabricated by this technique. Liquid Fe40Al exhibited excellent infilt ration ability, the distance of complete intrusion of liquid Fe40Al in the TiC s intered pre-form with density of 88%TD was over 7 mm after 5 min at the inf iltration temperature of 1 450 ℃. Microstructural observation by SEM and TEM also showed that liquid Fe40Al filled the very narrow gaps among TiC particles, the interfaces of TiC particles and F e40Al plastic ligaments being metallurgical bonded. TEM revealed that high densi ty of dislocations formed in Fe40Al ligaments during solidification, which favor the mechanical properties. Ti decomposed from TiC particles and dissolved into Fe40Al during infiltration. According to the compositional analysis of TEM-EDS, the concentration of Ti in Fe40Al ranges at 1at%～4at% depending on composite f a bricating conditions and the distance from the measuring point to the closest Ti C particles. XRD analysis indicated that the composites were composed of two pha ses, the original TiC and Fe 0.4Al 0.6 intermetallic. No new phas

关键词： TiC Composites System Melt Infiltration Ability and Microstructural Evolution of Fe40Al Fe

FORMATION AND CRYSTALLIZATION OF LEAD HALIDE BASED glassES

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Journal of Wuhan University of Technology(Materials Science) 1998年第2期13卷 9-15页

作者：程继健 E. China Univ. of Sci. and Technol. China Res. Institute of glass and ceramics E. China Univ. of Sci. and Technol. Shanghai 200237 China

A series of new glass compositions based on PbX2 (X: Cl, Br or I) have been studied. Binary and ternary glasses resulted from the association of PbI2, Pb-Cl-2, AgI, KCl and KBr. By means of differential scanning calorimetry (DSC), the mechanism and kinetics of crystallization process were studied. X-ray diffraction studies demonstrate that there is the formation of complicated crystalline phases in crystallized lead iodide based glasses. By heat treating halide glasses of appropriate composition under adequate heating temperature and duration, the lead iodide based glasses could be converted into glass-ceramics with microcrystal size less 1 mu m of which mechanical properties are improved.

关键词： formation of glass kinetic crystallization mechanical properties lead halide based glasses

Enhanced Performance of Osteoblasts by Silicon Incorporated Porous TiO_2 Coating

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Journal of Materials Science & Technology 2012年第2期28卷 109-117页

作者： Quanming Wang Hongjie Hu Yuqing Qiao Zhengxiang Zheng Junying Sun Orthopaedic department The First Affiliated Hospital of Soochow University 188 Shizi Street Suzhou 215006 China State Key Laboratory of High Performance ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

Silicon （Si） incorporated porous TiO2 coating （Si-TiO2） prepared on titanium （Ti） by micro-arc oxidation （MAO） technique was demonstrated to be cytocompatible in previous studies. In view of the potential clinical applications, a detailed in vitro study of the biological activity of Si-Ti02 coating, in terms of osteoblast （MC3T3-EI cells） morphology, proliferation, differentiation and mineralization was performed. Immunofluo- rescent staining indicated that cells seeded on the Si-TiO2 coating showed improved adhesion with developing mature cytoskeletons, which contained numerous distinct and well-defined actin stress fibers in the cell mem- branes compared with those on the Ti02 coating and Ti plate. Results from proliferation assay showed that the proliferation rate of cells seeded on the Si-TiO2coating was significantly faster than that on the TiO2 coating and Ti plate. Furthermore, the analysis of osteogenic gene expression demonstrated that the Si-Ti02 coating stimulated the expression of osteoblast-related genes and promoted differentiation and mineralization of MC3T3-EI cells. In addition, the Si-TiO2 coating differentially regulated Wnt signaling pathway by up-regulating the expression of low-density lipoprotein （LDL） receptor-related protein 5 （LrpS）, and downregulating the expression of Dickkopf-1 （Dkkl）. All together, these results indicate that the investigated titanium with Si-TiO2 coating is biocompatible and a good candidate material used as implants.

关键词： Micro-arc oxidation Silicon TiO2 Osteoblast Gene expression

Effect of comburent ratios on combustion synthesis of Eu-doped β-SiAlON green phosphors

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Journal of Rare Earths 2017年第5期35卷 430-435页

作者：葛一瑶田兆波陈莹孙思源张杰谢志鹏 State Key Laboratory of New ceramics and Fine Processing Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

SiAlON phosphors doped with rare earths have attracted much attention on the application of light emitting diode（LEDs） benefitting from their outstanding thermal stability, chemical stability and broad emission band properties. In this work, Eu-doped β-SiAlON green phosphors with composition Si（5.5）Al（0.5）O（0.5）N（7.5）：0.035Eu^2＋ were prepared by a highly efficient combustion synthesis（CS） method. The effect of comburent ratios（i.e., Si ＆ Al） were systematically investigated by adjusting the starting compositions of reactants. It was confirmed that the ratios of Si and Al reactants had an intense influence on the phase composition, microstructure and photoluminescence properties of as-synthesized phosphors by directly determining the systematic energy in CS. The as-prepared β-SiAlON：Eu^2＋ phosphors featured with high phase purity, uniform particle size of 3–5 μm, well-crystalline morphology and outstanding luminescent properties of green emission under UV or blue excitation were synthesized with 67.5 wt.% ratio of Si and no Al comburent.

关键词： combustion systematically crystalline luminescent outstanding excitation determining starting featured adjusting

Modification of CeO_2-ZrO_2 catalyst by potassium for NOx-assisted soot oxidation

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Journal of Environmental Sciences 2011年第1期23卷 145-150页

作者： DuanWeng Jia Li, Xiaodong Wu Zhichun Si State Key Laboratory of New ceramics & Fine Process Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

Potassium-modified ceria-zirconia catalyst was synthesized by wetness impregnation method. The ageing treatment was performed in static air at 800℃ for 20 hr to evaluate the thermal stability of the catalyst. The catalysts were characterized by X-ray diffraction, BET surface area, oxygen storage capacity, NOx-temperature programmed desorption and soot-temperature programmed oxidation measurements. By introduction of potassium, the maximum soot oxidation rate temperature （Tin） of the ceria-zirconia based catalyst decreased from 525 to 428℃ in the presence of NO under a loose contact mode. The shift of Tm of the K-modified catalyst after ageing is only 15℃. The enhanced activity of the aged catalyst mainly lies in the promotional effect of potassium on the NOx/oxygen storage capacity as well as the soot-catalyst contact.

关键词： CeO2-ZrO2 mixed oxides potassium soot combustion NOx storage oxygen storage capacity