Aitchison Hannah, Lu Hao, Ortiz de la Morena Rodrigo, Cebula Izabela, Zharnikov Michael, Buck Manfred
EaStCHEM School of Chemistry, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK.
Phys Chem Chem Phys. 2018 Jan 24;20(4):2731-2740. doi: 10.1039/c7cp06160a.
Assembly of 1,3,5-benzenetribenzoic acid (H3BTB) from solution on Au substrates modified by underpotential deposited Ag and Cu layers was studied by near edge X-ray absorption fine structure spectroscopy, X-ray photoelectron spectroscopy and scanning tunneling microscopy. Adsorption of H3BTB on Cu resulted in disordered layers with sporadic occurrence of ordered molecular aggregates. In contrast, highly ordered layers were obtained on Ag which exhibit a pronounced row structure and involve a monopodal bidentate adsorption geometry of the molecules through carboxylate coordinating bonding. The row structure arises from π-stacking of the molecules and is accompanied by hydrogen bonding interactions between the COOH groups of adjacent rows. As a consequence of the geometry of the H3BTB molecule and the dominance of intermolecular over molecule-substrate interactions, the SAM forms an open structure featuring a grooved surface and nanotunnels.
采用近边X射线吸收精细结构光谱、X射线光电子能谱和扫描隧道显微镜研究了1,3,5-苯三甲酸（H3BTB）在欠电位沉积银和铜层修饰的金基底上从溶液中组装的情况。H3BTB在铜上的吸附导致形成无序层，偶尔出现有序的分子聚集体。相比之下，在银上获得了高度有序的层，这些层呈现出明显的行结构，并且分子通过羧酸盐配位键以单足双齿吸附几何构型存在。行结构源于分子的π堆积，并伴随着相邻行的COOH基团之间的氢键相互作用。由于H3BTB分子的几何形状以及分子间相互作用优于分子-基底相互作用，自组装单分子层形成了具有沟槽表面和纳米隧道的开放结构。
