Mass Loading‐Independent Energy Storage with Reduced Graphene Oxide and Carbon Fiber

Large‐scale manufacturing of thick electrode films with high energy storage is critical for practical applications. Two‐dimensional materials are promising candidates due to their high surface areas to volume ratios. However, various studies have reported that the storage capacity of these two‐dimensional materials is highly dependent on the thickness of the films. Here, we demonstrate a scheme based on the reduced graphene oxide/carbon fiber composites as supercapacitor electrodes which demonstrate a mass loadings‐independent energy and power performances. Randomly oriented and interconnected carbon fibers are utilized to provide a framework to alleviate the restacking issues of reduced graphene oxide nanosheets and promoting ion flows in the networks. High capacitances maintain even the mass loadings up to 4 mg cm−2. An all‐solid symmetrical supercapacitor has been fabricated to power a LED light and also can power a commercial gas sensor, which shows the practical application potential. Avoiding restacking: A hierarchically‐structured architecture based on reduced graphene oxide/carbon fiber (RGO/CF) composites for supercapacitor electrodes with constant energy and power performances independent of mass loadings and high mechanical strength. The randomly oriented and interconnected CFs provide a framework to limit the restacking of RGO nanosheets to achieve high double‐layer capacitances of 125–225 F g−1, with varying mass loadings up to 4 mg cm−2.