Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, USA.
ACS Nano. 2012 Jun 26;6(6):5150-6. doi: 10.1021/nn300844g. Epub 2012 May 7.
Copper nanofiber networks, which possess the advantages of low cost, moderate flexibility, small sheet resistance, and high transmittance, are one of the most promising candidates to replace indium tin oxide films as the premier transparent electrode. However, the chemical activity of copper nanofibers causes a substantial increase in the sheet resistance after thermal oxidation or chemical corrosion of the nanofibers. In this work, we utilize atomic layer deposition to coat a passivation layer of aluminum-doped zinc oxide (AZO) and aluminum oxide onto electrospun copper nanofibers and remarkably enhance their durability. Our AZO-copper nanofibers show resistance increase of remarkably only 10% after thermal oxidation at 160 °C in dry air and 80 °C in humid air with 80% relative humidity, whereas bare copper nanofibers quickly become insulating. In addition, the coating and baking of the acidic PEDOT:PSS layer on our fibers increases the sheet resistance of bare copper nanofibers by 6 orders of magnitude, while the AZO-Cu nanofibers show an 18% increase.
铜纳米纤维网络具有成本低、柔韧性适中、方阻值小、透过率高的优点，是最有希望替代氧化铟锡薄膜作为首选透明电极的材料之一。然而，铜纳米纤维的化学活性导致纳米纤维的热氧化或化学腐蚀后，方阻值显著增加。在这项工作中，我们利用原子层沉积在电纺铜纳米纤维上包覆一层掺铝氧化锌（AZO）和氧化铝的钝化层，显著提高了它们的耐久性。我们的 AZO-铜纳米纤维在 160°C 的干燥空气中和 80°C 的相对湿度为 80%的潮湿空气中热氧化后，其电阻增加仅为 10%，而裸露的铜纳米纤维则迅速变为绝缘。此外，在我们的纤维上涂覆和烘焙酸性 PEDOT：PSS 层会使裸露的铜纳米纤维的方阻值增加 6 个数量级，而 AZO-Cu 纳米纤维的方阻值仅增加 18%。
