Wang Yan, Gong Shu, Wang Stephen J, Yang Xinyi, Ling Yunzhi, Yap Lim Wei, Dong Dashen, Simon George P, Cheng Wenlong
Department of Innovation Design Engineering, School of Design , Royal College of Art , London SW7 2EU , United Kingdom.
The Melbourne Centre for Nanofabrication , Clayton , Victoria 3800 , Australia.
ACS Nano. 2018 Oct 23;12(10):9742-9749. doi: 10.1021/acsnano.8b05019. Epub 2018 Sep 18.
Stretchable electronics may enable electronic components to be part of our organs-ideal for future wearable/implantable biodiagnostic systems. One of key challenges is failure of the soft/rigid material interface due to mismatching Young's moduli, which limits stretchability and durability of current systems. Here, we show that standing enokitake-like gold-nanowire-based films chemically bonded to an elastomer can be stretched up to 900% and are highly durable, with >93% conductivity recovery even after 2000 stretching/releasing cycles to 800% strain. Both experimental and modeling reveal that this superior elastic property originates from standing enokitake-like nanowire film structures. The closely packed nanoparticle layer sticks to the top of the nanowires, which easily cracks under strain, whereas the bottom part of the nanowires is compliant with substrate deformation. This leads to tiny V-shaped cracks with a maintained electron transport pathway rather than large U-shaped cracks that are frequently observed for conventional metal films. We further show that our standing nanowire films can serve as current collectors in supercapacitors and second skin-like smart masks for facial expression detection.
可拉伸电子器件或许能使电子元件成为我们器官的一部分，这对未来的可穿戴/植入式生物诊断系统而言是理想之选。关键挑战之一在于，由于杨氏模量不匹配，软/硬材料界面会失效，这限制了当前系统的拉伸性和耐用性。在此，我们展示了通过化学键合与弹性体相连的金针菇状金纳米线基薄膜，其可拉伸至900%，且具有高度耐用性，即便在以800%应变进行2000次拉伸/释放循环后，仍有>93%的电导率恢复率。实验和建模均表明，这种卓越的弹性性能源自金针菇状纳米线薄膜结构。紧密堆积的纳米颗粒层附着在纳米线顶部，该部分在应变下容易开裂，而纳米线底部则能顺应基底变形。这导致形成微小的V形裂纹，并保持电子传输路径，而非传统金属薄膜中常见的大U形裂纹。我们进一步表明，我们的直立纳米线薄膜可作为超级电容器中的集流体以及用于面部表情检测的类第二皮肤智能面罩。
