Kaulen Corinna, Homberger Melanie, Bourone Svenja, Babajani Ninet, Karthäuser Silvia, Besmehn Astrid, Simon Ulrich
Institute of Inorganic Chemistry and JARA - Fundamentals of Future Information Technologies, RWTH Aachen University , 52074 Aachen, Germany.
Langmuir. 2014 Jan 21;30(2):574-83. doi: 10.1021/la404110y. Epub 2014 Jan 7.
Integration of molecule-capped gold nanoparticles (AuNP) into nanoelectronic devices requires detailed knowledge about the AuNP-electrode interface. Here, we report the pH-dependent adsorption of amine or carboxylic acid-terminated gold nanoparticles on platinum or gold/palladium (30% Pd) alloy, respectively. We synthesized amine-terminated AuNP, applying a new solid phase supported approach, as well as AuNP exhibiting carboxylic acid as terminal groups. The pH-induced agglomeration of the synthesized AuNP was investigated by UV-vis, DLS, and ζ-potential measurements. Depending on the pH and the ionic strength of the AuNP solution a preferential adsorption on the different metals occurred. Thereby, we demonstrate that by choosing the appropriate functional group and adjusting the pH as well as the ionic strength a directed binding can be achieved, which is an essential prerequisite for applications of these particles in nanoelectronics. These findings will pave the way for a controlled designing of the interface between molecule-capped AuNP and metallic electrodes for applications in nanoelectronics.
将分子包覆的金纳米颗粒（AuNP）集成到纳米电子器件中需要深入了解AuNP与电极的界面。在此，我们分别报道了胺基或羧基封端的金纳米颗粒在铂或金/钯（30%钯）合金上的pH依赖性吸附。我们采用一种新的固相支持方法合成了胺基封端的AuNP以及以羧酸为端基的AuNP。通过紫外可见光谱、动态光散射和ζ电位测量研究了合成的AuNP的pH诱导团聚。根据AuNP溶液的pH值和离子强度，在不同金属上发生了优先吸附。由此，我们证明通过选择合适的官能团并调节pH值以及离子强度，可以实现定向结合，这是这些颗粒在纳米电子学中应用的一个基本前提。这些发现将为分子包覆的AuNP与金属电极之间的界面进行可控设计以用于纳米电子学应用铺平道路。
