▎ 摘　　要

A reduced graphene oxide/disodium terephthalate (RGO/DST) composite was prepared via ultrasonic-assisted co-precipitation. The ultrasonication of an azeotropic H2O/acetonitrile solution at elevated temperature induced simultaneous precipitations of RGO and DST with solvent evaporation. RGO/DST, collected before complete evaporation, showed that the DST was in a well-dispersed state between the graphene layers of the RGO, giving the RGO/DST a more densely stacked microstructure. When applied as an anode for sodium ion batteries (SIBs), the RGO/DST revealed an enhancement in Na+-storage capability, relative to composites prepared via simple evaporation (E-RGO/DST) and mechanical mixing (M-RGO/DST). The RGO/DST delivered a reversible capacity of 422mAh/g at a charge/discharge (C/D) rate of 50mA/g, in contrast to 368 and 303mAh/g for E-RGO/DST and M-RGO/DST, respectively. The superiority of the RGO/DST was maintained during repeated cycles. With an increase in the current densities, however, the reversible capability of the RGO/DST was decreased more substantially than that of the M-RGO/DST. Since Na+ diffusivity was greater in the RGO/DST than in the M-RGO/DST, this glitch in the high-rate performance of RGO/DST was considered because of a high level of charge-transfer impedance, in which a dense microstructure hampered the structural change of DST during reduction and oxidation.