The crystallization process of STS glass-ce-ramics was carried out in a constant temperature. The glass-ceramics still show good piezoelectric properties. The mecha-nism of orientation crystallization was investigated...The crystallization process of STS glass-ce-ramics was carried out in a constant temperature. The glass-ceramics still show good piezoelectric properties. The mecha-nism of orientation crystallization was investigated bv means of DTA.展开更多
A new niabate Sr6Ti7Nb9O42 was synthesized for the first time by solid state reaction in SrO-TiO2-Nb2O5 ternary system. The new compound was characterized by EPMA, XRD, SEM and DTA. The X-ray powder diffraction data o...A new niabate Sr6Ti7Nb9O42 was synthesized for the first time by solid state reaction in SrO-TiO2-Nb2O5 ternary system. The new compound was characterized by EPMA, XRD, SEM and DTA. The X-ray powder diffraction data of Sr6Ti7Nb9O42 were firstly reported in the paper. Sr6Ti7Nb9O42 crystallizes the hexagonal system with unit cell parameters a=8.9991(4) A,c= 11.5118(9)A. and space group P6/mcm (193), z=1. The calculated and measured densities are 4. 783 g/cm3 and 4. 764 g/cm3, respectively.展开更多
Commercial cathode material (LiCoO2) was modified by coating with a thin layer of SrO/Li2O/La2O3/Ta2O5/TiO2 for improving its performance in lithium ion battery. The morphology and structure of the modified cathode ...Commercial cathode material (LiCoO2) was modified by coating with a thin layer of SrO/Li2O/La2O3/Ta2O5/TiO2 for improving its performance in lithium ion battery. The morphology and structure of the modified cathode material were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The performance including cycling stability, diffusion coefficient under different voltage, C-rate discharge of the batteries with this modified cathode material was examined. The results showed that the battery with the coated cathode material could discharge at a large current density, and it possessed a stable cycle performance in the range from 3.0 V to 4.2 V. It was explained that the rate of Li ion diffusion increased in the batteries using SrO/Li2O/La2O3/Ta2O5/TiO2-coated LiCoO2 as the cathode and the coated layer could act as a fast ion conductor (SrO/Li2O/La2O3/Ta2O5/TiO2) and as a protecting shell to prevent LiCoO2particles from being attacked by the acidic electrolyte.展开更多
Atomic layer deposition (ALD) has become an essential deposition method for forming nanometer scale thin films in the microelectronics industry, and its applications have been extended to multi-component thin films,...Atomic layer deposition (ALD) has become an essential deposition method for forming nanometer scale thin films in the microelectronics industry, and its applications have been extended to multi-component thin films, as well as to single metal oxide films. In order to investigate the development of the surface structure of ultra-thin film qualitatively as well as quantitatively, ALD processes are simulated with a molecular scale. For this simulation, the film materials are deposited on a imaginary substrate that consists of small lattice. The deposition behaviors are described by using random deposition (RD) model or random deposition with surface relaxation (RDSR) model as the ALD growth mode, and the proposed model was applied to the deposition of SrO-TiO2 thin films. Through this work, growth characteristics such as surface morphology, deposited film coverage can be predicted.展开更多
基金This paper is aided financially by National Natural Science Foundation of China.
文摘The crystallization process of STS glass-ce-ramics was carried out in a constant temperature. The glass-ceramics still show good piezoelectric properties. The mecha-nism of orientation crystallization was investigated bv means of DTA.
基金Funded by Grant-in-Aid Project (No. 95-04) of International Centre for Diffraction Data.
文摘A new niabate Sr6Ti7Nb9O42 was synthesized for the first time by solid state reaction in SrO-TiO2-Nb2O5 ternary system. The new compound was characterized by EPMA, XRD, SEM and DTA. The X-ray powder diffraction data of Sr6Ti7Nb9O42 were firstly reported in the paper. Sr6Ti7Nb9O42 crystallizes the hexagonal system with unit cell parameters a=8.9991(4) A,c= 11.5118(9)A. and space group P6/mcm (193), z=1. The calculated and measured densities are 4. 783 g/cm3 and 4. 764 g/cm3, respectively.
基金supported by the Natural Science Foundation of Guangdong Province,China (06105562)the Foundation of Manyang Bureau of Sci-ence and Technology,China (07Y003-1)
文摘Commercial cathode material (LiCoO2) was modified by coating with a thin layer of SrO/Li2O/La2O3/Ta2O5/TiO2 for improving its performance in lithium ion battery. The morphology and structure of the modified cathode material were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The performance including cycling stability, diffusion coefficient under different voltage, C-rate discharge of the batteries with this modified cathode material was examined. The results showed that the battery with the coated cathode material could discharge at a large current density, and it possessed a stable cycle performance in the range from 3.0 V to 4.2 V. It was explained that the rate of Li ion diffusion increased in the batteries using SrO/Li2O/La2O3/Ta2O5/TiO2-coated LiCoO2 as the cathode and the coated layer could act as a fast ion conductor (SrO/Li2O/La2O3/Ta2O5/TiO2) and as a protecting shell to prevent LiCoO2particles from being attacked by the acidic electrolyte.
基金supported by grant-in-aid for the National Core Research Center Program (NCRC) from KOSEF and MOST (No. R15-2006-022-02004-0)
文摘Atomic layer deposition (ALD) has become an essential deposition method for forming nanometer scale thin films in the microelectronics industry, and its applications have been extended to multi-component thin films, as well as to single metal oxide films. In order to investigate the development of the surface structure of ultra-thin film qualitatively as well as quantitatively, ALD processes are simulated with a molecular scale. For this simulation, the film materials are deposited on a imaginary substrate that consists of small lattice. The deposition behaviors are described by using random deposition (RD) model or random deposition with surface relaxation (RDSR) model as the ALD growth mode, and the proposed model was applied to the deposition of SrO-TiO2 thin films. Through this work, growth characteristics such as surface morphology, deposited film coverage can be predicted.