School of Materials Science and Engineering and Tianjin Key Laboratory of Composites and Functional Materials, Tianjin University , Tianjin 300072, China.
ACS Nano. 2015 Jan 27;9(1):481-7. doi: 10.1021/nn505658u. Epub 2015 Jan 13.
A micrometer-thin solid-state supercapacitor (SC) was assembled using two pieces of porous carbon nanofibers/ultrathin graphite (pCNFs/G) hybrid films, which were one-step synthesized by chemical vapor deposition using copper foil supported Co catalyst. The continuously ultrathin graphite sheet (∼ 25 nm) is mechanically compliant to support the pCNFs even after etching the copper foil and thus can work as both current collector and support directly with nearly ignorable fraction in a SC stack. The pCNFs are seamlessly grown on the graphite sheet with an ohmic contact between the pCNFs and the graphite sheet. Thus, the accumulated electrons/ions can duly transport from the pCNFs to graphite (current collector), which results in a high rate performance. The maximum energy density and power density based on the whole device are up to 2.4 mWh cm(-3) and 23 W cm(-3), which are even orders higher than those of the most reported electric double-layer capacitors and pseudocapacitors. Moreover, the specific capacitance of the device has 96% retention after 5000 cycles and is nearly constant at various curvatures, suggesting its wide application potential in powering wearable/miniaturized electronics.
使用两块多孔碳纤维/超薄石墨（pCNFs/G）杂化薄膜组装了一种厚度仅为几微米的固态超级电容器（SC），该薄膜是通过在铜箔上使用钴催化剂一步化学气相沉积合成的。连续的超薄石墨片（约 25nm）具有机械顺应性，可以支撑 pCNFs，即使在蚀刻铜箔后也是如此，因此可以直接用作 SC 堆叠中的集流器和支撑体，几乎可以忽略不计。pCNFs 与石墨片之间具有欧姆接触，无缝地生长在石墨片上。因此，积累的电子/离子可以从 pCNFs 到石墨（集流器）适当传输，从而实现高倍率性能。基于整个器件的最大能量密度和功率密度分别高达 2.4mWhcm(-3)和 23Wcm(-3)，比大多数报道的双电层电容器和赝电容器高出几个数量级。此外，该器件的比电容在 5000 次循环后保持 96%的保留率，并且在各种曲率下几乎保持不变，这表明其在为可穿戴/小型化电子设备供电方面具有广泛的应用潜力。
