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机械力活化固相化学反应法制备Ce_xZr_(1-x)O_2纳米复合氧化物(英文)

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Journal of Shanghai University(English Edition) 2008年第2期12卷 184-188页

作者：郑育英黄慧民黄世炎孙明 College of Light and Chemical Engineering Guangdong University of Technology

Nanometer cerium-zirconium oxide solution Ce1-x ZrxO2 was synthesized by mechanically activated solid state re- action at middle-low temperatures, with Ce2（CO3）3, ZrOCl2-SH2O and H2C2O4·2H2O as raw materials. The crystal structure and microstructure of the nanometer Ce1-x Zrx O2 were studied with X-ray diffractometry （XRD） and transmission electron microscope （TEM）. The results show that the product is single-cubic-phase solid solution with an average crystal size 19.64 nm. In this article, the influence of surface active agent is also evaluated. Mechanically activated solid state reaction for the preparation of Ce1-xZrxO2 is a new technique of green chemistry without solvent and waste.

关键词： ceria zirconia surface active agent solid state reaction.

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Abstracts from International Journal of Minerals,Metallurgy and Materials

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Rare Metals 2011年第4期30卷 432-432页

The time-temperature-transformation （TIT） diagrams of F-free mold fluxes were constructed using single hot thermocouple technique （SITtT） and confocal scanning laser microscopy （CSLM） to study the crystallization behavior of F-free mold fluxes. The tendency of crystallization is found to increase whereas the incubation time decreases with increasing basicity. zirconia addition enhances the crystallization tendency due to its limited solubility in the slag melt and the solid particles acting as nucleation sites. Pseudo-wollastonite is found to precipitate in the slag with low basicity （CS-I and CS-2）, kilchoanite and larnite are formed with further increasing basicity （CS-3）, and lamite is finally formed as the basicity beyond unit （CS-4）. The crystal morphology changes with varying compositions and isothermal temperatures. The measured growth rate is found to be linear with time under isothermal conditions and decreases with increasing isothermal temperature.

关键词： continuous casting mold fluxes crystallization zirconia crystal growth

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增韧ZrO2陶瓷的研究

南京工业大学学报(自然科学版) 1988年第1期 58-63页

作者：丘泰张跃盛绪敏

以YO为固溶剂采用机械粉碎法制备的亚微米级ZrO粉末为原料,制造出高强度、高韧性的ZrO陶瓷。通过制定合理的配方以及控制烧成工艺条件,可以在坯体中获得大量的亚稳四方ZrO。当YO加入量为2.5mol％时,抗折强度达978MPa,断裂韧性达15.1MPam... 详细信息

以YO为固溶剂采用机械粉碎法制备的亚微米级ZrO粉末为原料,制造出高强度、高韧性的ZrO陶瓷。通过制定合理的配方以及控制烧成工艺条件,可以在坯体中获得大量的亚稳四方ZrO。当YO加入量为2.5mol％时,抗折强度达978MPa,断裂韧性达15.1MPam~1/2。其增韧机理属于应力诱导相变增韧。

关键词： zirconia yttria hot-pressing mechanical properties toughen

Mechanisms of Methanol Decomposition and Oxidation on ZrO2(-111):A First-Principles Study

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Mechanisms of Methanol Decomposition and Oxidation on ZrO2(-...

Synthesis and Characterization of Pd/ZrO2/MWCNTs for Direct Formic Acid Fuel Cells

第十三届全国量子化学会议

作者： Yan Li Tingting Liu School of Petroleum and Chemical Engineering Dalian University of TechnologyPanjin Campus

Methanol is a major volatile organic compounds(VOCs). Considering that emission of VOCs can cause air pollution [1,2,3], the design and development of novel strategies for VOCs control are of great value. Previous expermients[4] showed that zirconia exhibit good catalytic activity for the methanol oxidation, however, the mechanism is not clear at present.In this work, the adsorption, decomposition and oxidation of methanol on hydroxylated monoclinic zirconia(-1 1 1) have been studied using density functional theory(DFT-GGA) and slab periodic model. Among the four adsorption structures(two for top sites and two for bridge sites), the top site for methanol is the most stable adsorption site, because there is a hydrogen bond between O-H and terminal hydroxyl group. The adsorption energy is-1.08 eV. Two reaction pathways corresponding to methanol interacted with terminal-hydroxyl groups(path A) and bridge-hydroxyl group(path B) were studied by CI-NEB method. The results show path B is more favorable, and the rate-determining step of path B is CHO+ O→CHO+ OH.The results of this work should provide a useful guidance for the design of new catalysts.

关键词： methanol oxidation zirconia reaction mechanism a first-principles study

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Synthesis and Characterization of Pd/ZrO2/MWCNTs for Direct ...

The hot corrosion behavior in vanadate environment and thermal cycling behaviors of YTZ and 2GYTZ for thermal barrier coating applications

第十一届海峡两岸超微颗粒学术研讨会暨中国颗粒学会超微颗...

作者： Yuh-Jing Chiou Yi-Lan Chang Hong-Ming Lin Andrzej Borodzinski Leszek Stobinski Department of Chemical Engineering Tatung University Department of Materials Engineering Tatung University Institute of Physical Chemistry Polish Academy of Sciences

In order to promote the application of DFAFCs,nano palladium catalyst should beprepared with good electrocatalytic performance and stability to be applied as anodiccatalyst for formic acid oxidation.In our previous study,Pd/AO-MWCNTs catalyst has goodcurrent density of formic acid oxidation,because of the well dispersion and nanoparticlesize caused larger surface area.For transition metal oxides increase the formation of OHad species at lower potentials that can facilitate the oxidation of poisonous COad species to CO2 on a Pd surface,and the promotion of a direct pathway(hydrogenation) for FAO.By adding metal oxide,CO poison situation may be suppressed.In this study,tetragonal zirconia was deposited on MWCNTs,and Pd was reduced by x-ray photosynthesis method via synchrotron beamline.The results reveal that Pd was successfully prepared on MWCNTs with metal doped zirconia modification.The metal modified zirconium dioxide keeps tetragonal structure.While Pd:ZrO2/AO-MWCNTs have not only tetragonal,but also monoclinic structure.The Pd particle size of metal is around 5 nm.For electrocatalytic performance,Pd on Au doped Zr O2/AO-MWCNTs had the best electrocatalytic surface area and maximum formic acid oxidation current.Pd/(Pd:ZrO2/AO-MWCNTs) had the most stable potential.

关键词： DFAFCs Pd zirconia x-ray photosynthesis AO-MWCNTs

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The hot corrosion behavior in vanadate environment and therm...