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The benzyl alcohol route is used to decorate reduced graphene oxide (RGO) nanosheets with iron oxide (FeOx) nanoparticles. The resulting FeOx/RGO composites combine both electrical double-layer capacitive and pseudocapacitive behaviors of RGO and FeOx, respectively, owing to the hybrid nanostructure. In 1 M Na2SO4 aqueous electrolyte, the capacitance of the FeOx/RGO electrode reaches 126 F g−1 in a negative potential range from −0.8 to 0.0 V (vs. Ag/AgCl) and 97 F g−1 in the extended potential window from −0.8 to +0.7 V (vs. Ag/AgCl). By using the benzyl alcohol route, a higher concentration of iron precursor leads to full surface coverage of the RGO nanosheets by smaller FeOx nanoparticles, forming a close-packed layer that limits the restacking of RGO nonosheets in the dry state. The resulting FeOx/RGO composite gains the same power capability as RGO and a higher energy density than raw FeOx, owing to this well-designed morphology,.