权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Study on State-sensitive Observation of Gold and Platinum Nano-particles and Promoter Sites by XAFS combined with X-ray Fluorescence Spectrometry

XAFS结合X射线荧光光谱法对金铂纳米粒子及启动子位点的状态敏感观测研究

基本信息

批准号：
17550073
负责人：
IZUMI Yasuo
金额：
$ 1.09万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2006
项目状态：
已结题

项目摘要

This work was performed as the extension of series of our state-sensitive XAFS(X-ray absorption fine structure) studies applied to catalysts and environmental materials. State-sensitive Sn Kα_1-selecting XAFS spectra were measured for Pt-Sn catalysts suppressing the core-hole lifetime broadening of Sn K level. The presence of Sn sites adsorbed on Pt particles (mean particle size approximately equal 1 nm) highly dispersed over SiO_2 surface and the electronic state of Sn were demonstrated. Also, series of Au/TiO_2 catalysts were synthesized. The mean Au particle size was controlled homogeneous to between 2.9 and 8.7 nm. Based on state-sensitive Au Lα_1-selecting XAFS, the presence of neutra1, δ^-, and δ^+ sites were demonstrated in Au nano-particles.First major, remarkable progress during this period was that the improvement of energy resolution of state-sensitive XAFS due to the advancement of X-ray beam stability at SPring-8 beamline. The beam position stability exhibited similar effect to reduce the beam size at the sample position. As the result, the state-sensitive structural analyses of each site in Au nano-particles became more familiar, technically less-demanding. Second, in common with our study of vanadium catalysts excited under visible light (Priority Area Research "Nano-Dynamics"), measurement technique of state-sensitive XAFS under on-reaction conditions was established. As the result, we were successful to directly detect electron donation from Au(δ^+)sites to O_2 molecule under on-reaction condition. The measurement is regarded as to detect the key intermediate in the low-temperature CO oxidation.

这项工作是我们应用于催化剂和环境材料的一系列状态敏感XAFS（X射线吸收精细结构）研究的扩展。本文测量了抑制SnK能级的芯-空穴寿命展宽的Pt-Sn催化剂的SnK α_1选择XAFS谱。结果表明，Pt颗粒（平均粒径约为1 nm）高度分散在SiO_2表面，Sn在Pt颗粒上存在吸附位，Sn的电子态也得到了证实。并合成了系列Au/TiO_2催化剂。平均Au颗粒尺寸被均匀地控制在2.9和8.7 nm之间。基于状态灵敏Au Lα_1-选择XAFS，在Au纳米粒子中发现了中性1，δ^-和δ^+的存在，这一时期的第一个主要的，显著的进展是由于SPring-8光束线上X射线束稳定性的提高，提高了状态灵敏XAFS的能量分辨率。光束位置稳定性表现出类似的效果，以减少样品位置处的光束尺寸。因此，Au纳米颗粒中每个位点的状态敏感结构分析变得更加熟悉，技术要求更低。第二，与我们在可见光下激发的钒催化剂的研究（优先领域研究“纳米动力学”）一样，建立了在反应条件下的状态敏感XAFS测量技术。结果表明，在反应条件下，我们成功地直接探测到了Au（δ^+）位对O_2分子的电子贡献。该方法可用于CO低温氧化反应中关键中间体的检测。

项目成果

期刊论文数量（30）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

State-sensitive Monitoring of Active andPromoter Sites. Applications to Au/titania and Pt-Sn/silica Catalysts by XAFS Combined with X-ray Fluorescence Spectrometry

活性位点和启动子位点的状态敏感监控。

DOI：
发表时间：
2007
期刊：
X-Ray Absorption Fine Structure 13th International Conference Vol.882
影响因子：
0
作者：
Yasuo Izumi;Dishad Masih;Jean-Pierre Candy;Hideaki Yoshitake;Yasuko Terada;Hajime Tanida;and Tomoya Uruga
通讯作者：
and Tomoya Uruga

Creation of Micro and Mesoporous Fe^<III> Materials utillzing Organic Template followed by Carboxylates Exchange for the Low Concentrations of Arsenic Removal

利用有机模板制备微孔和介孔 Fe^<III> 材料，然后进行羧酸盐交换以实现低浓度除砷

DOI：
发表时间：
2006
期刊：
Microporous and Mesoporous Materials 94・1-3
影响因子：
0
作者：
Yasuo Izumi;Dilshad Masih;KenichiAika;Yoshimi Seida
通讯作者：
Yoshimi Seida

X-ray Absorption Fine Structure Combined with X-ray Fluorescence Spectrometry. Part 18. Tin Site Structure of Pt-Sn Catalyst

X 射线吸收精细结构与 X 射线荧光光谱法相结合。

DOI：
发表时间：
2007
期刊：
Materials Letters 61(18)
影响因子：
0
作者：
Yasuo Izumi;Dilshad Masih;Eric Roisin;Jean-Pierre Candy;Hajime Tanida;and Tomoya Uruga
通讯作者：
and Tomoya Uruga

Erratum to "Creation of Micro and Mesoporous Fe^<III> Materials utilizing Organic Template followed by Carboxylates Exchange for the Low Concentrations of Arsenic Removal"

“利用有机模板创建微孔和介孔 Fe^<III> 材料，然后进行羧酸盐交换以实现低浓度砷去除”的勘误表