Ionic liquid-assisted synthesis of rGO wrapped three-dimensional CuS ordered nanoerythrocytes with enhanced performance for asymmetric supercapacitors

•A novel rGO wrapped 3D CuS ordered nanoerythrocyte structure has been designed.•The superstructures are fabricated via the interactions of π-π stacking along the aligned hydrogen bonds in [BMIm]Cl IL.•The CuS-OEs/rGO exhibits high capacity of 203 C g−1, and can maintain 92.5% of initial capacity after 10000 cycles.•The asymmetric device CuS-OEs/rGO//AC shows high energy density of 16.7 Wh kg−1 at a power density of 681 W kg−1.

rGO wrapped three-dimensional (3D) CuS ordered nanoerythrocytes (CuS-OEs/rGO) were fabricated in the presence of ionic liquid ([BMIm]Cl) and GO under solvothermal conditions and investigated as electrode materials for supercapacitors. CuS-OEs/rGO exhibited high specific capacity, good rate capability, and excellent cycling stability, compared with two-dimensional (2D) CuS disordered nanoplates/rGO (CuS-DPs/rGO) and three-dimensional (3D) CuS disordered nanoflowers (CuS-DFs). Furthermore, CuS-OEs/rGO based asymmetric supercapacitor displayed impressive rate performance (retain 69.8% at 10 A g−1), outstanding cyclability (capacitance retention of 90.8% after 10000 cycles at 2 A g−1), and high-energy density (16.7 Wh kg−1 at a power density of 681 W kg−1).

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