State Key Laboratory for Metallic Matrix Composite Materials, School of Materials Science and Engineering, Shanghai Jiao Tong University , Shanghai 200240, P. R. China.
ACS Appl Mater Interfaces. 2017 May 24;9(20):17051-17059. doi: 10.1021/acsami.7b02478. Epub 2017 May 11.
Wire-shaped supercapacitors (SCs) based on shape memory materials are of considerable interest for next-generation portable and wearable electronics. However, the bottleneck in this field is how to develop the devices with excellent electrochemical performance while well-maintaining recoverability and flexibility. Herein, a unique asymmetric electrode concept is put forward to fabricate smart wire-shaped SCs with ultrahigh energy density, which is realized by using porous carbon dodecahedra coated on NiTi alloy wire and flexible graphene fiber as yarn electrodes. Notably, the wire-shaped SCs not only exhibit high flexibility that can be readily woven into real clothing but also represent the available recoverable ability. When irreversible plastic deformations happen, the deformed shape of the devices can automatically resume the initial predesigned shape in a warm environment (about 35 °C). More importantly, the wire-shaped SCs act as efficient energy storage devices, which display high volumetric energy density (8.9 mWh/cm), volumetric power density (1080 mW/cm), strong durability in multiple mechanical states, and steady electrochemical behavior after repeated shape recovery processes. Considering their relative facile fabrication technology and excellent electrochemical performance, this asymmetric electrode strategy produced smart wire-shaped supercapacitors desirable for multifunctional portable and wearable electronics.
基于形状记忆材料的线状超级电容器 (SCs) 引起了人们对下一代便携式和可穿戴电子产品的极大兴趣。然而，该领域的瓶颈在于如何开发具有优异电化学性能的器件，同时保持可恢复性和灵活性。在此，提出了一种独特的非对称电极概念，通过使用多孔碳十二面体涂覆在 NiTi 合金丝和柔性石墨烯纤维上作为纱线电极来制造具有超高能量密度的智能线状 SCs。值得注意的是，线状 SCs 不仅表现出高柔韧性，可轻松编织成真正的衣物，而且还具有可用的可恢复能力。当发生不可逆的塑性变形时，器件的变形形状可以在温暖的环境（约 35°C）下自动恢复到初始预定形状。更重要的是，线状 SCs 作为高效储能装置，具有高体积能量密度（8.9 mWh/cm）、体积功率密度（1080 mW/cm）、在多种机械状态下的强大耐用性以及在重复形状恢复过程后的稳定电化学行为。考虑到其相对简单的制造技术和优异的电化学性能，这种非对称电极策略产生的智能线状超级电容器非常适合多功能便携式和可穿戴电子产品。
