Enhancing electrochemical performance of Fe3O4/graphene hybrid aerogel with hydrophilic polymer

Graphene hybrid aerogels have attracted attention as electrode materials because of their unique porous architectures. However, their electrochemical performance is limited by the intrinsic hydrophobicity and the ease of aggregation of graphene nanosheets. We demonstrate a unique methodology to produce graphene hybrid aerogels through assembly of graphene nanosheets, nanometer-scale ferroferric oxide (Fe3O4), and hydrophilic poly(vinyl alcohol) (PVA) into three-dimensional hierarchical macrostructures. Electrochemical performance measurements exhibit a significant improvement in the specific capacitance of this ternary hybrid aerogel with remarkable cycling stability. Specifically, the specific capacitance is nearly 6.6 times higher than that of the neat graphene aerogel, and a cycling capacitance retention rate of 99% was achieved after 2000 cycles at a high current density of 0.5 A g(-1). Electrochemical impedance spectroscopy measurements demonstrate a lower resistance in the Fe3O4/graphene/PVA aerogel electrode compared with that of both neat graphene and Fe3O4/graphene aerogel electrodes. The obtained graphene hybrid aerogels with outstanding cycling performance and high energy density are very promising as electrode materials for supercapacitors. (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45566.