表面上的二维聚合物形成:洞察前体流动性和反应性的作用
Marco Bieri1, Manh-Thuong Nguyen, Oliver Gröning
1Empa, Swiss Federal Laboratories for Materials Science and Technology, Feuerwerkerstrasse 39, CH-3602 Thun, and Ueberlandstrasse 129, CH-8600 Duebendorf, Switzerland. marco.bieri@empa.ch
Journal of the American Chemical Society
|November 4, 2010
概括
循环-m- (CHP) 的表面辅助组装产生2D聚合物. 基质选择 (Cu,Au,Ag) 决定了网络形态,金属表面影响了CHP基的脱和合.
科学领域:
- 表面科学是一门科学.
- 材料化学 材料化学
- 聚合物化学 聚合物化学
背景情况:
- 合成具有控制网络结构的二维聚合物是材料科学中的一个重大挑战.
- 表面辅助组装提供了一个创建有序分子网络的途径.
研究的目的:
- 研究在硬币金属表面 (Cu,Au,Ag) 上使用表面辅助组装,将六合替代的环-m-烯 (CHP) 组合成二维聚烯网络.
- 阐明不同金属基板在控制CHP分子脱,激素形成和随后合中的作用.
- 了解基质特性对生成的二维聚合物网络的形态学和排序的影响.
主要方法:
- 组合实验技术:扫描道显微镜 (STM) 和X射线光电谱 (XPS).
- 计算建模:密度函数理论 (DFT) 的计算.
- 模拟:蒙特卡洛模拟用于模拟扩散和合动态.
主要成果:
- 在Cu{111},Au{111}和Ag{111}表面的CHP在室温下脱,形成表面稳定的CHP基 (CHPR).
- 在CHPR之间形成热激活的共价键,在不同的金属基板上具有不同的激活温度.
- 聚烯网络的基底依赖形态:分支在Cu上,混合在Au上,在Ag上高度有序/密集.
- DFT的计算显示了Cu和Ag表面的CHPR扩散和合的不同能量障碍.
- 蒙特卡洛模拟证实,扩散和合之间的平衡决定了网络结构.
结论:
- 币金属基板的选择极大地影响了CHP激素的脱,扩散和合动力学.
- 这种对动力学的控制导致Cu,Au和Ag表面上的2D聚烯网络具有不同的形态.
- 表面辅助组装通过选择合适的金属基板,为设计2D聚合物架构提供了一条通用的途径.
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