对Ni@TiO2-x催化剂的界面协同催化反应的洞察
Ming Xu1, Siyu Yao2, Deming Rao1
1State Key Laboratory of Chemical Resource Engineering, Beijing Advanced Innovation Center for Soft Matter Science and Engineering , Beijing University of Chemical Technology , Beijing 100029 , People's Republic of China.
Journal of the American Chemical Society
|July 19, 2018
概括
这项研究揭示了使用Ni@TiO2-x催化剂进行水气转移 (WGS) 反应的新氧化还原机制. 这些发现为设计高活性异质催化剂提供了洞察力.
科学领域:
- 不同质的催化
- 材料科学
- 表面化学
背景情况:
- 接口协同催化对于支持的金属催化剂至关重要,特别是在水气转移 (WGS) 反应中.
- 了解金属支相互作用的原子级机制是增强催化剂活性和选择性的关键.
- 目前对WGS中可降解氧化物支的界面协同催化学的知识仍然模两可.
研究的目的:
- 阐明水气转移反应 (WGS) 中的界面协同催化机制.
- 在TiO2-x (Ni@TiO2-x) 支持下制造和描述具有优异的催化性能的Ni纳米粒子.
- 为设计先进的异质催化剂提供基本见解.
主要方法:
- 通过对尼二氧化 (LDH) 前体的拓变化制造Ni@TiO2-x.
- 在现场显微镜观察催化剂结构.
- 在现场和操作 EXAFS,在现场 DRIFTS 和温度编程的氧化还原 (TPR) 测量.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 在WGS反应中,Ni@TiO2-x催化剂表现出色.
- 现场研究显示了Ni@TiO2-x催化剂的部分封装结构.
- 证实了涉及界面Ni物种 (Niδ-) 和氧空缺 (Ov) 的新型氧化还原机制.
- DFT计算证实了接口点是低激活能障碍 (0.35 eV) 的最佳水解离点.
结论:
- 该研究建立了WGS反应中界面协同催化的一种新氧化还原机制.
- 这些发现突显了介面Niδ-物种和氧气空缺在水分离中的关键作用.
- 这项工作为高活性异质催化剂的合理设计提供了基本的理解.
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