金属有机链的表面氧化还原活性组件,具有单位Pt (II)
Daniel Skomski1, Christopher D Tempas, Kevin A Smith
1Department of Chemistry, Indiana University , 800 E. Kirkwood Ave., Bloomington, Indiana 47405, United States.
Journal of the American Chemical Society
|June 25, 2014
概括
研究人员开发了一种方法来控制表面上的单点的氧化状态,使用有机连接物. 这一进步对于为未来的应用创造高度选择性的异质催化剂至关重要.
科学领域:
- 表面化学 表面化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 在异质催化中实现高选择性往往需要精确控制金属活性位点.
- 在表面上稳定明确的过渡金属单个位点是开发高级催化剂的关键.
- 使用有机连接物进行选择性催化,控制表面金属位点的氧化状态仍然是一个挑战.
研究的目的:
- 研究表面上明确的过渡金属单个位点的形成和稳定.
- 探索使用有机连接物协调的方法,以在表面金属部位中达到定义的氧化状态.
- 开发高度选择性的异质催化剂的新途径.
主要方法:
- 使用金属与单晶黄金表面上的二甲基四氨酸连接体相互作用.
- 采用X射线光电子谱学 (XPS) 来证明金属-联体氧化还原活性.
- 使用分子分辨率扫描探针显微镜 (SPM) 阐明金属有机网络的结构.
- 进行对照实验,使用氧化还原无活性的二四素联结体.
主要成果:
- 在-二甲基二四氨酸接口展示了金属连接体的氧化还原活性.
- 揭示了黄金表面上形成一个有序的金属有机网络的形成.
- 确定了双酸结合点和氧化还原活性功能组对于达到定义的Pt(II) 氧化状态至关重要.
- 展示了对单位中心的氧化状态和结构的联体介导控制.
结论:
- 连接物协调可以有效地控制金属表面单位金属中心的氧化状态和结构.
- 双酸结合和氧化还原活性联体的组合使电荷转移到特定的Pt (II) 状态.
- 这种方法为下一代异质催化剂的增强选择性提供了一条途径.
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