McCarty Gregory S, Moody Benjamin, Zachek Matthew K
Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh NC 27695.
J Electroanal Chem (Lausanne). 2010 May 1;643(1-2):9-14. doi: 10.1016/j.jelechem.2010.03.018.
The ability to quickly and inexpensively fabricate planar solid state nanogaps has enabled research to be effectively performed on devices down to just a few nanometers. Here, nanofabricated electrode pairs with electrode-to-electrode spacings of <4, 6 and 20 nm are utilized for monitoring an electroactive molecules, dopamine, in ionic solution. The results show a several order of magnitude enhancement of the electrochemical signal, collected current, for the solid state nanogaps with 6 nm electrode-electrode spacings as compared to traditional microelectrodes. The data from the <4 nm and 20 nm solid state nanogaps verify that this enhancement is due to cycling of the redox molecules in the confined geometry of the nanogap. In addition the data collected for the <4 nm nanogap emphasizes and reinforces that scaling does have limits and that as device sizes move to the few nanometer scale, the influence of a molecule's size and other physical properties becomes increasingly important and can eventually dominate the generated signals.
能够快速且低成本地制造平面固态纳米间隙，使得针对尺寸小至仅几纳米的器件的研究得以有效开展。在此，电极间距分别为<4纳米、6纳米和20纳米的纳米制造电极对被用于监测离子溶液中的电活性分子多巴胺。结果表明，与传统微电极相比，电极间距为6纳米的固态纳米间隙的电化学信号（收集到的电流）增强了几个数量级。来自<4纳米和20纳米固态纳米间隙的数据证实，这种增强是由于氧化还原分子在纳米间隙的受限几何结构中循环所致。此外，为<4纳米纳米间隙收集的数据强调并强化了尺寸缩放确实存在极限，并且随着器件尺寸缩小到几纳米尺度，分子大小和其他物理性质的影响变得越来越重要，最终可能主导所产生的信号。
