• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>ACS catalysis >Hydrogen Adsorption, Dissociation, and Spillover on Ru-10 Clusters Supported on Anatase TiO2 and Tetragonal ZrO2 (101) Surfaces
【24h】

Hydrogen Adsorption, Dissociation, and Spillover on Ru-10 Clusters Supported on Anatase TiO2 and Tetragonal ZrO2 (101) Surfaces

机译：锐钛矿型TiO2和四方ZrO2（101）表面支撑的Ru-10团簇上的氢吸附，解离和溢出

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The scope of this work is to study at atomistic level the mechanism of hydrogen spillover promoted by metal particles on oxide surfaces. By means of Density Functional Theory calculations with Hubbard correction (DFT+U) we have analyzed the adsorption and dissociation of molecular hydrogen on anatase titania, a-TiO2 (101), and tetragonal zirconia, t-ZrO2 (101), surfaces in the presence of a supported Ru-10 nanocluster. The role of the supported metal particle is essential as it favors the spontaneous dissociation of H-2, a process which does not occur on the bare oxide surface. At low hydrogen coverage, the H atoms prefer to stay on the Ru-10 particle, charge accumulates on the metal cluster, and reduction of the oxide does not take place. On a hydroxylated surface, the presence of a Ru nanoparticle is expected to promote the reverse effect, i.e. hydrogen reverse spillover from the oxide to the supported metal. It is only at high hydrogen coverage, resulting in the adsorption of several H-2 molecules on the metal cluster, that it becomes thermodynamically favorable to have hydrogen transfer from the metal to the O sites of the oxide surface. In both TiO2, and ZrO2 surfaces the migration of an H atom from the Ru cluster to the surface is accompanied by an electron transfer to the empty states of the support with reduction of the oxide surface.
机译：这项工作的范围是在原子水平上研究氧化物表面上的金属粒子促进氢溢出的机理。通过采用Hubbard校正（DFT + U）的密度泛函理论计算，我们分析了分子氢在锐钛矿型二氧化钛，a-TiO2（101）和四方氧化锆，t-ZrO2（101）的表面上的吸附和解离。受支持的Ru-10纳米簇的存在。负载金属颗粒的作用至关重要，因为它有助于H-2的自发解离，这种过程在裸露的氧化物表面上不会发生。在低氢覆盖率下，H原子倾向于保留在Ru-10颗粒上，电荷积累在金属簇上，并且不会发生氧化物还原。在羟基化的表面上，预期Ru纳米颗粒的存在会促进反向作用，即氢从氧化物向载体金属的反向溢出。仅在高氢覆盖率下，导致几个H-2分子吸附在金属簇上，使氢从金属转移到氧化物表面的O位置在热力学上变得有利。在TiO2和ZrO2表面上，H原子从Ru团簇向表面的迁移都伴随着电子转移到载体的空态，同时还原了氧化物表面。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号