...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, C. Nanomaterials and interfaces >Insight into the Reaction Mechanism of the Reduction of NO by H-2 on the Singly Dispersed Bimetallic Pt(Rh)Co-4/Co3O4 Catalysts: A First-Principles Study
【24h】

Insight into the Reaction Mechanism of the Reduction of NO by H-2 on the Singly Dispersed Bimetallic Pt(Rh)Co-4/Co3O4 Catalysts: A First-Principles Study

机译：在单独分散的Bimetallic Pt（RH）CO-4 / CO3O4催化剂上，洞察H-2的反应机理：第一原理研究

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 restructured singly dispersed bimetallic sites M(1)A(n) supported on the metallic oxide surface have drawn much attention due to their different catalytic performances for the reaction mechanisms of nitric oxide reduction by H-2 on the catalysts with singly dispersed bimetallic sites MCo4(M = Pt and Rh) anchored on Co3O4. They were investigated by using DFT+U methods with periodic slab models. The adsorption and dissociation of NO, possible intermediates, and reaction pathways for N-containing products in this process were identified on the Pt(Rh)Co-4/Co3O4 (110)-B surfaces. It is found that the surface oxygen vacancy (O-vac) generated by the hydrogenation of the lattice oxygen plays a key role in the catalytic reduction of NO, and O-vac and bimetallic sites of MCo4 are the active sites responsible for NO dissociation and N-2 formation. The presence of H atoms has a larger promotion effect for NO dissociation on RhCo4/Co3O4 than on PtCo4/Co3O4, producing the major intermediates NH and N, respectively; accordingly, different N-2 formation pathways were identified on MCo4/Co3O4 (110)-B. The hydrogenation of O or OH is the rate-controlling step in whole catalytic cycle for N-2 formation, and the energy barrier for this step is almost identical, suggesting that PtCo4/Co3O4 (110)-B and RhCo4/Co3O4 (110)-B have similar reaction activities. The products of N2O and NH3 are energetically unfavorable to be formed on both surfaces because of the large energy barriers. The present results show that the Co3O4 -based catalysts consisting of the singly dispersed bimetallic sites of MCo4 have high catalytic activity and selectivity toward N-2, which is consistent with the experimental observations.
机译：支撑在金属氧化物表面上的重组单粒分散的双金属位点M（1）A（n）具有引起广泛关注，因为它们不同的催化性能对催化剂的一氧化氮还原由H-2的反应机制，单粒分散的双金属位点MCO4（M = PT和RH）锚定在CO3O4上。通过使用具有周期性平板模型的DFT + U方法来研究它们。在Pt（RH）CO-4 / CO3O4（110）-B表面上鉴定在该方法中的NO，可能的中间体和反应途径的吸附和解离和反应途径。得到的是，通过晶格氧的氢化产生的表面氧空位（O-VAC）在催化还原的催化还原中起关键作用，MCO4的O-VAC和双金属位点是负责不分离的活性位点N-2形成。 H原子的存在在rhCO 4 / CO3O4上没有对PTCO 4 / CO3O4的解离的较大促进效果，分别产生主要中间体NH和N;因此，在MCO 4 / CO 3 O 4（110）-B上鉴定出不同的N-2形成途径。 O或OH的氢化是N-2形成的全催化循环中的速率控制步骤，并且该步骤的能量屏障几乎相同，表明PTCO4 / CO3O4（110）-B和rHCO4 / CO3O4（110） -B具有类似的反应活动。由于大量的能量屏障，N2O和NH3的产品在两个表面上都是强大的不利的。本结果表明，由MCO 4的单分散的双金属位点组成的CO3O4基于催化剂具有高催化活性和朝向N-2的选择性，这与实验观察一致。

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