Barone Carlo, Bertoldo Monica, Capelli Raffaella, Dinelli Franco, Maccagnani Piera, Martucciello Nadia, Mauro Costantino, Pagano Sergio
Dipartimento di Fisica "E.R. Caianiello", Università degli Studi di Salerno, I-84084 Fisciano, Italy.
CNR-SPIN Salerno, c/o Università degli Studi di Salerno, I-84084 Fisciano, Italy.
Nanomaterials (Basel). 2021 Feb 24;11(3):565. doi: 10.3390/nano11030565.
The electric transport properties of flexible and transparent conducting bilayers, realized by sputtering ultrathin gold nanometric layers on sodium-alginate free-standing films, were studied. The reported results cover a range of temperatures from 3 to 300 K. In the case of gold layer thicknesses larger than 5 nm, a typical metallic behavior was observed. Conversely, for a gold thickness of 4.5 nm, an unusual resistance temperature dependence was found. The dominant transport mechanism below 70 K was identified as a fluctuation-induced tunneling process. This indicates that the conductive region is not continuous but is formed by gold clusters embedded in the polymeric matrix. Above 70 K, instead, the data can be interpreted using a phenomenological model, which assumes an anomalous expansion of the conductive region upon decreasing the temperature, in the range from 300 to 200 K. The approach herein adopted, complemented with other characterizations, can provide useful information for the development of innovative and green optoelectronics.
研究了通过在海藻酸钠自支撑膜上溅射超薄金纳米层实现的柔性透明导电双层的电输运特性。报道的结果涵盖了从3到300 K的温度范围。当金层厚度大于5 nm时，观察到典型的金属行为。相反，对于4.5 nm的金厚度，发现了异常的电阻温度依赖性。低于70 K时的主要输运机制被确定为涨落诱导隧穿过程。这表明导电区域不是连续的，而是由嵌入聚合物基质中的金簇形成的。相反，在70 K以上，数据可以用一个唯象模型来解释，该模型假设在300到200 K的温度范围内，导电区域在温度降低时会异常膨胀。本文采用的方法，辅以其他表征手段，可以为创新型绿色光电子学的发展提供有用信息。
