Hierarchically novel bead-curtain-like zinc-cobalt sulfides arrays toward high energy density hybrid supercapacitors via morphology engineering

Abstract

Rational design of the electrode materials in distinctive architecture and tailored composition is critical for regulating their electrochemical properties. Herein, the novel porous zinc-cobalt sulfides (ZCS) bead-curtain-like arrays (BCA) supported by three-dimensional Ni foam (NF) (denoted as ZCS/NF BCA) are fabricated as advanced electrode for supercapacitors (SCs), which exhibit remarkable electrochemical performances in respect of superb capacity of ~837 C g−1 (specific capacitance of ~1860 F g−1) at 1 A g−1 and ultra-long cycling stability (~92.9% retention after 5000 cycles at 6 A g−1). Furthermore, the assembled hybrid supercapacitors based on ZCS/NF BCA delivers ultrahigh energy density of ~88 Wh kg−1 with a maximum power density of ~800 W kg−1. The excellent properties may be ascribed to the combined contributions from the hierarchical bead-curtain architecture of ZCS/NF BCA composite and the bimetallic sulfide with abundant valence states for rich redox reactions.