Construction of Nickel Cobalt Sulfide/Double Hydroxide Heterostructure on Carbon Cloth as Free-Standing Electrode for Supercapacitors

Abstract

Combining the advantages of nickel cobalt sulfide and layered double hydroxide ex-hibits great potentials in designing of high-performance electrode materials for super-capacitors. Here, a representative nickel cobalt sulfide/layered double hydroxide het-erostructure has been deposited on carbon cloth to construct free-standing electrode for supercapacitor, marked as NCS@NCOH/CC. Benefited from the nanoporous struc-ture and ultrathin nanosheets, especially the enhanced electronic transfer kinetics due to heterostructure design, the electrode presents potential capacitive performance. Specifically, when increasing the current density from 1 to 20 A g-1, the DSC declines from 1339.1 to 1149.9 F g-1, corresponding to a retention of 85.9%, manifesting excep-tional rate performance. When charging and discharging under 10 A g-1 for 10,000 cy-cles, the DSC can maintain 71.3%, illustrating good cycle durability. Moreover, the fabricated NCS@NCOH/CC//AC/NF hybrid capacitor also demonstrates unique cyclic stability of 86.9% energy retention after 10,000 cycles under 5 A g-1. And an energy density of 20.52 Wh kg-1 at 1604.2 W kg-1 can be realized, corresponding to a tenfold increase compared with AC/NF//AC/NF symmetric capacitor. This work proves the feasibility of fabricating high performance transition metal sulfide@ hydroxide hetero-structure electrode by an electrodeposition method.