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

rGO wrapped three-dimensional (3D) CuS ordered nanoerythrocytes (CuS-OEs/rGO) were fabricated in the presence of ionic liquid ([BNIm]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)). (C) 2017 Elsevier B.V. All rights reserved.