Suzuki Takayuki, Lutz Theresa, Payer Dietmar, Lin Nian, Tait Steven L, Costantini Giovanni, Kern Klaus
Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569, Stuttgart, Germany.
Phys Chem Chem Phys. 2009 Aug 14;11(30):6498-504. doi: 10.1039/b905125b. Epub 2009 Jun 10.
Terephthalic acid (TPA) deposited on Si(111)-7 x 7, Si(111)-square root 3 x square root 3-Ag and Ag(111) has been studied as a model system to understand how much passivated semiconductor surfaces differ from semiconductor and metal surfaces in respect of supramolecular self assembly. By scanning tunneling microscopy it is found that TPA molecules do not form any ordered supramolecular structure on the pristine semiconductor surface, due to a strong molecule-substrate interaction. On the contrary, TPA has a weaker interaction with Si(111)-square root 3 x square root 3-Ag, leading to the formation of an ordered supramolecular layer stabilized by carboxyl hydrogen bonds. These structures are very similar to the supramolecular layer of TPA formed on Ag(111), indicating that the two substrates behave similarly for what concerns the adsorption of functional organic molecules. However, the deposition of Fe on the TPA layers on Si(111)-square root 3 x square root 3-Ag does not induce the formation of two-dimensional metal-organic frameworks which, on the contrary, readily develop on Ag(111). Possible origins of this difference are discussed.
对沉积在Si(111)-7×7、Si(111)-√3×√3-Ag和Ag(111)上的对苯二甲酸(TPA)进行了研究，以此作为一个模型系统，来了解在超分子自组装方面，钝化的半导体表面与半导体和金属表面有多大差异。通过扫描隧道显微镜发现，由于分子与衬底之间的强相互作用，TPA分子在原始半导体表面上不会形成任何有序的超分子结构。相反，TPA与Si(111)-√3×√3-Ag的相互作用较弱，导致形成由羧基氢键稳定的有序超分子层。这些结构与在Ag(111)上形成的TPA超分子层非常相似，这表明在功能性有机分子的吸附方面，这两种衬底的表现相似。然而，在Si(111)-√3×√3-Ag上的TPA层上沉积Fe不会诱导形成二维金属有机框架，相反，在Ag(111)上很容易形成这种框架。讨论了这种差异可能的成因。
