Dipartimento di Scienze Chimiche and CSGI, Università degli Studi di Catania, V.le A. Doria 6, I 95125, Catania, Italy.
Nanoscale. 2019 Mar 14;11(11):4788-4793. doi: 10.1039/c8nr09027k.
The fabrication of stable, highly conductive molecular nano-junctions is one of the main research goals in the field of molecular electronics. In this paper we report on the self-assembly and functional characterisation of highly conductive molecular wires, based on mixed-metal polynuclear complexes, at the surface of a transparent conductive oxide. The adopted synthetic approach involves metal-coordination reactions on oxide surfaces, pre-functionalised with a monolayer of terpyridine moieties that are used as anchoring sites for the integration of ditopic, redox-active ruthenium-bisterpyridine molecules through iron(ii) centres. By the stepwise iteration of the iron-coordination reaction, molecular wires of the desired length can be prepared, which alternate iron and ruthenium centres in the wire backbone. The stepwise assembly of the wires at the transparent conductive oxide surface was characterised by means of UV-Vis spectroscopy and, at the nanoscale, by means of ToF-SIMS measurements. The electrical characteristics of the wires were obtained by the liquid-metal eutectic-gain nano-junction technique, with results that show good electron transport capabilities along the wires. The demonstrated feasibility of the integration of these metal-polypyridinic, redox-active, conductive wires at the surface of a transparent and conductive oxide, and the evidence for good electrical conduction indicates prospective applications in the field of nanoscale molecular optoelectronics.
稳定、高导电的分子纳结的制造是分子电子学领域的主要研究目标之一。本文报道了在透明导电氧化物表面上，基于多核配合物的混合金属的高度导电分子线的自组装和功能特性。所采用的合成方法涉及在预先功能化的卟啉单层上的氧化表面上的金属配位反应，该卟啉单层用作通过铁(ii)中心整合双齿、氧化还原活性的钌双吡啶分子的锚固位点。通过铁配位反应的逐步迭代，可以制备所需长度的分子线，该分子线在分子线骨架中交替铁和钌中心。通过紫外可见光谱和纳秒级的 ToF-SIMS 测量对分子线在透明导电氧化物表面上的逐步组装进行了表征。通过液态金属共晶增益纳结技术获得了分子线的电特性，结果表明沿着分子线具有良好的电子输运能力。在透明导电氧化物表面上整合这些金属-多吡啶、氧化还原活性、导电分子线的可行性得到了证明，并且良好的电导率表明在纳米尺度分子光电领域具有广阔的应用前景。
