Effect of a crystalline phase of TiO2 photocatalysts on the photodeposition of Rh metal nanoparticles
Effect of a crystalline phase of TiO2 photocatalysts on the photodeposition of Rh metal nanoparticles
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TiO2光催化剂晶相对Rh金属纳米粒子光沉积的影响
DOI：
10.1016/j.cattod.2013.09.024
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发表时间：
2014
期刊：
影响因子：
5.3
通讯作者：
T. Tanak
中科院分区：
文献类型：
--
作者：
A. Yamamoto;J. Ohyama;K. Teramura;T. Shishido;T. Tanak
采用原位时间分辨能量色散x射线吸收精细结构谱（DXAFS）、透射电子显微镜（TEM）和x射线光电子能谱（XPS）研究了tio2晶相在锐钛矿和金红石相tio2光催化剂上光沉积过程中tio2晶相的影响。重要的因素既不是它的晶粒尺寸也不是它的比表面积，而是它的晶相。原位时间分辨DXAFS分析表明，在TiO2的锐钛矿相和金红石相上均出现了尺寸均匀的Rh金属纳米颗粒，而仅在TiO2的金红石相上，Rh金属纳米颗粒的出现率随光照射时间的增加而降低。TEM观察和XPS深度分析表明，光沉积的Rh金属纳米颗粒裸露在金红石表面，但由于Rh金属纳米颗粒与TiO2−δ之间的强金属支撑相互作用（SMSI），在锐钛矿表面部分被TiO2覆盖。
Effect of a crystalline phase of TiO2is investigated in the photodeposition processes of Rh metal nanoparticles on TiO2photocatalysts having anatase and rutile phase by means of in situ time-resolved energy dispersive X-ray absorption fine structure spectroscopy (DXAFS), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The important factor was neither its crystallite size nor its specific surface area, and was the crystalline phase. In situ time-resolved DXAFS analysis clarified that the Rh metal nanoparticles with a uniform size appear on both anatase and rutile phases of TiO2, whereas the appearance rate of Rh metal nanoparticles decreases with the photoirradiation time only on the rutile phase of TiO2. The TEM observation and XPS depth analysis revealed that the bare surface of photodeposited Rh metal nanoparticles on the rutile is exposed, although that on the anatase is partially covered with TiO2due to strong metal-support interaction (SMSI) between Rh metal nanoparticle and TiO2−δ.