材料期刊网

Synthesis, Characterization and Photocatalytic Activity of TiO₂ Film/Bi₂O₃ Microgrid Heterojunction

Liugang Wang Junying Zhang Chunzhi Li Hailing Zhu Wenwen Wang

材料科学技术（英文）

TiO₂ film modified by Bi₂O₃ microgrid array was successfully fabricated by using a microsphere lithography method. The structure and morphology of TiO₂ film, Bi₂O₃ film and TiO₂ film/Bi₂O₃ microgrid heterojunction were characterized through X-ray diffraction, atomic force microscopy and scanning electron microscopy. The optical transmittance spectra and the photocatalytic degradation capacity of these samples to rhodamine B were determined via ultraviolet-visible spectroscopy. The results indicated that the coupled system showed higher photocatalytic activity than pure TiO₂ and Bi₂O₃ films under xenon lamp irradiation. The enhancement of the photocatalytic activity was ascribed to the special structure, which could improve the separation of photo-generated electrons and holes, enlarge the surface area and extend the response range of TiO₂ film from ultraviolet to visible region.

关键词: Thin films , TiO2 , Bi2O3 microgrid , Photocatalysis

Synthesis, Characterization and Photocatalytic Activity of TiO₂ Film/Bi₂O₃ Microgrid Heterojunction

Liugang Wang Junying Zhang Chunzhi Li Hailing Zhu Wenwen Wang

材料科学技术（英文）

TiO₂ film modified by Bi₂O₃ microgrid array was successfully fabricated by using a microsphere lithography method. The structure and morphology of TiO₂ film, Bi₂O₃ film and TiO₂ film/Bi₂O₃ microgrid heterojunction were characterized through X-ray diffraction, atomic force microscopy and scanning electron microscopy. The optical transmittance spectra and the photocatalytic degradation capacity of these samples to rhodamine B were determined via ultraviolet-visible spectroscopy. The results indicated that the coupled system showed higher photocatalytic activity than pure TiO₂ and Bi₂O₃ films under xenon lamp irradiation. The enhancement of the photocatalytic activity was ascribed to the special structure, which could improve the separation of photo-generated electrons and holes, enlarge the surface area and extend the response range of TiO₂ film from ultraviolet to visible region.

关键词: Thin films , TiO2 , Bi2O3 microgrid , Photocatalysis

Two-step magnetization in a spin-chain system on the triangular lattice: Wang-Landau simulation

Physical Review B

The Wang-Landau algorithm is used to study the thermodynamic and magnetic properties of triangular spin-chain system based on two-dimensional Ising model in order to understand the magnetic-order dynamics in Ca(3)Co(2)O(6) compound. The calculated results demonstrate that the equilibrium state of the rigid spins produces the two-step magnetization curve at low temperature even when the random-exchange term is considered. This work indicates that the four-step magnetization behavior observed experimentally must be due to the nonequilibrium magnetization.

关键词: calcium compounds;exchange interactions (electron);Ising model;magnetisation;thermodynamics;one-dimensional ca3co2o6;density-of-states;compound ca3co2o6;phase-diagram;proteins;crystal

Ion sputter erosion in metallic glass-A response to "Comment on: Homogeneity of Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass" by L-Y. Chen, Y-W. Zeng, Q-P. Cao, B-J. Park, Y-M. Chen, K. Hono, U. Vainio, Z-L. Zhang, U. Kaiser, X-D. Wang, and J-Z Jiang J. Mater. Res. 24, 3116 (2009)

Journal of Materials Research

The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.

关键词: room-temperature

First-principle study of electronic properties of Ti3Si1-xAlxC2 solid solutions

Journal of Physics and Chemistry of Solids

The layered ternary ceramics Ti3SiC2 and Ti3AlC2 are isostructural and can form Ti3Si1-xAlxC2 solid solutions combining the advanced properties of both compounds [H.B. Zhang, Y.C. Zhou, Y.W. Bao, M.S. Li, Improving the oxidation resistance of Ti3SiC2 by forming a Ti3Si0.90Al0.1C2 solid solution, Acta Mater. 52 (2004) 3631-3637; E.D. Wu, J.Y. Wang, H.B. Zhang, Y.C. Zhou, K. Sun, Y.J. Xue, Neutron diffraction studies of Ti3Si0.9Al0.1C2 compound, Mater. Lett. 59 (2005) 2715-2719; J.Y. Wang, Y.C. Zhou, First-principles study of equilibrium properties and electronic structure of Ti3Si0.75Al0.25C2 solid solution, J. Phys.: Condens. Matter 15 (2003) 5959-5968; Y.C. Zhou, J.X. Chen, J.Y. Wang, Strengthening of Ti3AlC2 by incorporation of Si to form Ti3Al1-xSixC2 solid solutions, Acta. Mater. 54 (2006) 1317-1322]. In the present work, the solid solutions of Ti3Si1-xAlxC2 (x = 0, 0.25, 0.33, 0.5, 0.67, 0.75, 1) are investigated by first-principle calculations based on pseudo-potential plan-wave method within the density functional theory framework. The results show that as Al content increases in the solid solution, all the bonds have weakened to certain extents, which lead to an unstable structure both energetically and geometrically. The calculated results are compared and discussed with the reported data for the Ti3Si1-xAlxC2 solid solutions. (c) 2007 Elsevier Ltd. All rights reserved.

关键词: ceramics;ab initio calculations;electronic structure;electrical;conductivity;oxidation behavior;mechanical-properties;ti3sic2;temperature;ti3alc2;air;si

Jian ZHANG/Langhong Lou

材料科学技术（英文）

关键词:

ON SPINODAL BOUNDARIES OF Al-Li ALLOYS

WEI Yinghui , WANG Xiaotian (School of Materials Scince and Engineering , Xi'an Jiaotong University , Xi'an 710049 , China Manuscript received 10 Mareh , 1994)

金属学报(英文版)

The spinodal decomposition can occur in Al-Li alloys containing 5.8-14.2 at.% Li at room temperature. The modutated structure wavelength is approximately 3.1 nm for com mercial Al-LI alloys. The limit composition of the miscibility gap is 3.66 -16.06 at.%Li at 298 K. The highest temperature of the miscibility gap is 377 K.

关键词: : Al-Li alloy , null , null

大爆炸核合成相关的8Li(d, p)9Li反应截面测量

李志宏 , 柳卫平 , 白希祥 , 郭冰 , 连钢 , 颜胜权 , 王宝祥 , 陆昀 , 曾晟 , 苏俊

原子核物理评论 doi:10.3969/j.issn.1007-4627.2005.01.006

利用8Li次级束测量了质心系能量7.8 MeV 2H(8Li, 9Li)1H反应的角分布, 导出了8Li(d, p)9Li反应的天体物理S因子及9Li→8Li+n虚衰变的渐近归一化系数.

关键词: 8Li(d,p)9Li反应 , 角分布 , 天体物理S因子 , 渐近归一化系数

CRYSTAL STRUCTURE OF γ-Li_xFe_2O_3 WITH ELECTROCHEMICAL INSERTION OF Li

HUANG Jianshun CHEN Junming Shanghai Institute of Metallurgy , Academia Sinica , Shanghai , China Research Associate , Shanghai Institute of Metallurgy , Academia Sinica , Shanghai 200050 , China

金属学报(英文版)

Crystal structure of γ-Li_xFe_2O_3,inserted Li electrochemically,was studied by Moss- bauer spectroscopy together with X-ray diffraction,XPS and electrochemical method,On the insertion of Li at low current density,the crystal structure is keeping original spinel; while at higher current density or by thermal activation,owing to violent movement of Li~+ ions,part of crystal structure transforms into rock type similar to face-centered cubic structure of ferrous oxide.The transition channels during insertion of Li~+ ions and limitation of Li~+ ions inserted were discussed.

关键词: null , null , null

Al—Li合金的晶界断裂

姚大平 , 张匀 , 胡壮麒 , 李依依

材料研究学报

本文研究了两种晶粒组织的二元Al-Li 合金拉伸性能与断裂行为。结果表明Al-Li 合金力学性能与晶粒尺寸有关,其断裂行为决定于PFZ 内平面滑移或晶界沉淀相与滑移的交互作用。

关键词: Al—Li合金 , intergranular fracture , planar slip