Atomic-Scale Visualization of Stepwise Growth Mechanism of Metal-Alkynyl Networks on Surfaces
Atomic-Scale Visualization of Stepwise Growth Mechanism of Metal-Alkynyl Networks on Surfaces
复制标题
表面金属炔基网络逐步生长机制的原子尺度可视化
DOI：
10.1021/jacs.0c04311
复制
发表时间：
2020
影响因子：
15
通讯作者：
Liu Pei-Nian
中科院分区：
文献类型：
--
作者：
Shu Chen-Hui;He Yan;Zhang Ruo-Xi;Chen Jian-Le;Wang An;Liu Pei-Nian
金属-有机网络的生长机制是金属-有机网络研究中最吸引人的话题之一。然而，它的研究仍然被认为是一个重大的挑战。本文利用扫描隧道显微镜，在原子尺度上研究了金属-炔基网络在Ag(111)和Au(111)表面的生长机制。在1，3，5-三(氯乙炔)苯与银(111)的反应中，393K时形成蜂窝状的银-炔基网络，只有短链中间体生成。相反，相同的前驱体在503K时在Au(111)表面形成了蜂窝状的Au-炔基网络，逐级退火导致了一个逐步的演化过程，在这个过程中，三个氯炔基键的顺序激活导致了作为中间体的二聚体、锯齿链和新的手性网络的形成。此外，密度泛函理论计算表明，氯原子在协助金属-炔基键断裂形成氯-金属-炔基中起着关键作用，这保证了断裂/生成平衡的可逆性，这是形成规整的大规模金属有机网络的关键。
One of the most appealing topics in the study of metal–organic networks is the growth mechanism. However, its study is still considered a significant challenge. Herein, using scanning tunneling microscopy, the growth mechanisms of metal–alkynyl networks on Ag(111) and Au(111) surfaces were investigated at the atomic scale. During the reaction of 1,3,5-tris(chloroethynyl)benzene on Ag(111), honeycomb Ag-alkynyl networks formed at 393 K, and only short chain intermediates were observed. By contrast, the same precursor formed honeycomb Au–alkynyl networks on Au(111) at 503 K. Progression annealing led to a stepwise evolution process, in which the sequential activation of three Cl-alkynyl bonds led to the formation of dimers, zigzag chains, and novel chiral networks as the intermediates. Moreover, density functional theory calculations indicate that chlorine atoms are crucial in assisting the breakage of metal-alkynyl bonds to form Cl-metal-alkynyl, which guarantees the reversibility of the break/formation equilibration as the key to forming regular large-scale organometallic networks.